Make scene safer

app/src/main/java/com/hippo/ehviewer/UrlOpener.java

@@ -17,10 +17,12 @@
 package com.hippo.ehviewer;
 
 import android.app.Activity;
+import android.content.ActivityNotFoundException;
+import android.content.Context;
 import android.content.Intent;
-import android.content.pm.PackageManager;
-import android.content.pm.ResolveInfo;
 import android.net.Uri;
+import android.provider.Browser;
+import android.support.annotation.NonNull;
 import android.support.customtabs.CustomTabsIntent;
 import android.text.TextUtils;
 import android.widget.Toast;
@@ -36,7 +38,7 @@ public final class UrlOpener {
     private UrlOpener() {
     }
 
-    public static void openUrl(Activity activity, String url, boolean ehUrl, boolean customTabs) {
+    public static void openUrl(@NonNull Context context, String url, boolean ehUrl, boolean customTabs) {
         if (TextUtils.isEmpty(url)) {
             return;
         }
@@ -47,17 +49,19 @@ public final class UrlOpener {
         if (ehUrl) {
             Announcer announcer = EhUrlOpener.parseUrl(url);
             if (null != announcer) {
-                intent = new Intent(activity, MainActivity.class);
+                intent = new Intent(context, MainActivity.class);
                 intent.setAction(StageActivity.ACTION_START_SCENE);
                 intent.putExtra(StageActivity.KEY_SCENE_NAME, announcer.getClazz().getName());
                 intent.putExtra(StageActivity.KEY_SCENE_ARGS, announcer.getArgs());
-                activity.startActivity(intent);
+                intent.setFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
+                context.startActivity(intent);
                 return;
             }
         }
 
         // CustomTabs
-        if (customTabs) {
+        if (customTabs && context instanceof Activity) {
+            Activity activity = (Activity) context;
             String packageName = CustomTabsHelper.getPackageNameToUseFixed(activity);
             if (packageName != null) {
                 new CustomTabsIntent.Builder()
@@ -70,15 +74,12 @@ public final class UrlOpener {
         }
 
         // Intent.ACTION_VIEW
-        intent = new Intent(Intent.ACTION_VIEW);
-        intent.setData(uri);
-        PackageManager pm = activity.getPackageManager();
-        ResolveInfo ri = pm.resolveActivity(intent, 0);
-        if (ri != null) {
-            activity.startActivity(intent);
-            return;
+        intent = new Intent(Intent.ACTION_VIEW, uri);
+        intent.putExtra(Browser.EXTRA_APPLICATION_ID, context.getPackageName());
+        try {
+            context.startActivity(intent);
+        } catch (ActivityNotFoundException e) {
+            Toast.makeText(context, R.string.error_cant_find_activity, Toast.LENGTH_SHORT).show();
         }
-
-        Toast.makeText(activity, R.string.error_cant_find_activity, Toast.LENGTH_SHORT).show();
     }
 }

app/src/main/java/com/hippo/ehviewer/ui/CommonOperations.java

@@ -217,6 +217,7 @@ public final class CommonOperations {
         client.execute(request);
     }
 
+    // TODO Add context if activity and context are different style
     public static void startDownload(final MainActivity activity, final GalleryInfo galleryInfo, boolean forceDefault) {
         final DownloadManager dm = EhApplication.getDownloadManager(activity);
 

app/src/main/java/com/hippo/ehviewer/ui/MainActivity.java

@@ -339,7 +339,7 @@ public final class MainActivity extends StageActivity
             BaseScene baseScene = (BaseScene) scene;
             mRightDrawer.removeAllViews();
             View drawerView = baseScene.onCreateDrawerView(
-                    getLayoutInflater(), mRightDrawer, savedInstanceState);
+                    baseScene.getLayoutInflater2(), mRightDrawer, savedInstanceState);
             if (drawerView != null) {
                 mRightDrawer.addView(drawerView);
                 mDrawerLayout.setDrawerLockMode(DrawerLayout.LOCK_MODE_UNLOCKED, Gravity.RIGHT);

app/src/main/java/com/hippo/ehviewer/ui/scene/AnalyticsScene.java

@@ -16,6 +16,7 @@
 
 package com.hippo.ehviewer.ui.scene;
 
+import android.content.Context;
 import android.os.Bundle;
 import android.support.annotation.Nullable;
 import android.view.LayoutInflater;
@@ -58,7 +59,7 @@ public class AnalyticsScene extends BaseScene implements View.OnClickListener {
         TextView text = (TextView) ViewUtils.$$(view, R.id.text);
 
         text.setText(Html.fromHtml(getString(R.string.analytics_explain)));
-        text.setMovementMethod(new LinkMovementMethod2(getActivity()));
+        text.setMovementMethod(LinkMovementMethod2.getInstance());
 
         mCancel.setOnClickListener(this);
         mOk.setOnClickListener(this);
@@ -79,18 +80,25 @@ public class AnalyticsScene extends BaseScene implements View.OnClickListener {
 
     @Override
     public void onClick(View v) {
+        Context context = getContext2();
+        if (null == context) {
+            return;
+        }
+
         if (mCancel == v) {
             Settings.putEnableAnalytics(false);
         } else if (mOk == v) {
             Settings.putEnableAnalytics(true);
             // Start Analytics
-            Analytics.start(getContext());
+            Analytics.start(context);
         }
         Settings.putAskAnalytics(false);
 
         // Start new scene and finish it self
-        ((MainActivity) getActivity()).startSceneForCheckStep(
-                MainActivity.CHECK_STEP_ANALYTICS, getArguments());
+        MainActivity activity = getActivity2();
+        if (null != activity) {
+            activity.startSceneForCheckStep(MainActivity.CHECK_STEP_ANALYTICS, getArguments());
+        }
         finish();
     }
 }

app/src/main/java/com/hippo/ehviewer/ui/scene/BaseScene.java

@@ -16,6 +16,8 @@
 
 package com.hippo.ehviewer.ui.scene;
 
+import android.content.Context;
+import android.content.res.Resources;
 import android.os.Bundle;
 import android.support.annotation.IdRes;
 import android.support.annotation.Nullable;
@@ -151,14 +153,52 @@ public abstract class BaseScene extends SceneFragment {
         return mViewCreated;
     }
 
-    @Override
-    public void onActivityCreated(Bundle savedInstanceState) {
-        super.onActivityCreated(savedInstanceState);
-        if (savedInstanceState != null) {
-            onRestoreInstanceState(savedInstanceState);
+    @Nullable
+    public Context getContext2() {
+        return super.getContext();
+    }
+
+    @Nullable
+    public Resources getResources2() {
+        Context context = getContext2();
+        if (null != context) {
+            return context.getResources();
+        } else {
+            return null;
         }
     }
 
-    protected void onRestoreInstanceState(Bundle savedInstanceState) {
+    @Nullable
+    public MainActivity getActivity2() {
+        FragmentActivity activity = getActivity();
+        if (activity instanceof MainActivity) {
+            return (MainActivity) activity;
+        } else {
+            return null;
+        }
+    }
+
+    @Nullable
+    public LayoutInflater getLayoutInflater2() {
+        FragmentActivity activity = getActivity();
+        if (null != activity) {
+            return activity.getLayoutInflater();
+        } else {
+            return null;
+        }
+    }
+
+    public void hideSoftInput() {
+        FragmentActivity activity = getActivity();
+        if (null != activity) {
+            ActivityHelper.hideSoftInput(activity);
+        }
+    }
+
+    public void showSoftInput(@Nullable View view) {
+        FragmentActivity activity = getActivity();
+        if (null != activity && null != view) {
+            ActivityHelper.showSoftInput(activity, view);
+        }
     }
 }

app/src/main/java/com/hippo/ehviewer/ui/scene/CookieSignInScene.java

@@ -36,7 +36,6 @@ import com.hippo.ehviewer.client.EhCookieStore;
 import com.hippo.ehviewer.client.EhUrl;
 import com.hippo.ehviewer.client.EhUtils;
 import com.hippo.rippleold.RippleSalon;
-import com.hippo.util.ActivityHelper;
 import com.hippo.yorozuya.AssertUtils;
 import com.hippo.yorozuya.ViewUtils;
 
@@ -90,7 +89,7 @@ public class CookieSignInScene extends BaseScene implements EditText.OnEditorAct
     public void onViewCreated(View view, @Nullable Bundle savedInstanceState) {
         super.onViewCreated(view, savedInstanceState);
 
-        ActivityHelper.showSoftInput(getActivity(), mIpbMemberId);
+        showSoftInput(mIpbMemberId);
     }
 
     @Override
@@ -144,7 +143,8 @@ public class CookieSignInScene extends BaseScene implements EditText.OnEditorAct
     }
 
     public void enter() {
-        if (null == mIpbMemberIdLayout || null == mIpbPassHashLayout ||
+        Context context = getContext2();
+        if (null == context || null == mIpbMemberIdLayout || null == mIpbPassHashLayout ||
                 null == mIpbMemberId || null == mIpbPassHash) {
             return;
         }
@@ -165,10 +165,10 @@ public class CookieSignInScene extends BaseScene implements EditText.OnEditorAct
             mIpbPassHashLayout.setError(null);
         }
 
-        ActivityHelper.hideSoftInput(getActivity());
+        hideSoftInput();
 
         if (!checkIpbMemberId(ipbMemberId) || !(checkIpbPassHash(ipbPassHash))) {
-            new AlertDialog.Builder(getContext()).setTitle(R.string.waring)
+            new AlertDialog.Builder(context).setTitle(R.string.waring)
                     .setMessage(R.string.wrong_cookie_warning)
                     .setNegativeButton(R.string.i_dont_think_so, null)
                     .setPositiveButton(R.string.i_will_check_it, new DialogInterface.OnClickListener() {
@@ -192,12 +192,12 @@ public class CookieSignInScene extends BaseScene implements EditText.OnEditorAct
     }
 
     private void storeCookie(String id, String hash) {
-        Context context = getContext();
+        Context context = getContext2();
         if (null == context) {
             return;
         }
 
-        EhUtils.signOut(getContext());
+        EhUtils.signOut(context);
 
         EhCookieStore store = EhApplication.getEhCookieStore(context);
         store.add(newCookie(EhCookieStore.KEY_IPD_MEMBER_ID, id, EhUrl.DOMAIN_E));

app/src/main/java/com/hippo/ehviewer/ui/scene/CrashScene.java

@@ -78,15 +78,18 @@ public class CrashScene extends BaseScene implements View.OnClickListener {
 
     @Override
     public void onClick(View v) {
-        if (mSend == v && null != mCrash) {
-            ActivityHelper.sendEmail(getActivity(), EhApplication.getDeveloperEmail(),
+        MainActivity activity = getActivity2();
+
+        if (mSend == v && null != mCrash && null != activity) {
+            ActivityHelper.sendEmail(activity, EhApplication.getDeveloperEmail(),
                     "I found a bug in EhViewer !", mCrash);
         }
         Crash.resetCrashFile();
 
         // Start new scene and finish it self
-        ((MainActivity) getActivity()).startSceneForCheckStep(
-                MainActivity.CHECK_STEP_CRASH, getArguments());
+        if (null != activity) {
+            activity.startSceneForCheckStep(MainActivity.CHECK_STEP_CRASH, getArguments());
+        }
         finish();
     }
 }

app/src/main/java/com/hippo/ehviewer/ui/scene/DownloadLabelsScene.java

@@ -16,6 +16,7 @@
 
 package com.hippo.ehviewer.ui.scene;
 
+import android.content.Context;
 import android.content.DialogInterface;
 import android.graphics.drawable.Drawable;
 import android.graphics.drawable.NinePatchDrawable;
@@ -52,6 +53,7 @@ import com.hippo.ehviewer.R;
 import com.hippo.ehviewer.dao.DownloadLabel;
 import com.hippo.util.DrawableManager;
 import com.hippo.view.ViewTransition;
+import com.hippo.yorozuya.AssertUtils;
 import com.hippo.yorozuya.ViewUtils;
 
 import java.util.List;
@@ -77,7 +79,7 @@ public class DownloadLabelsScene extends ToolbarScene {
     @Override
     public void onCreate(@Nullable Bundle savedInstanceState) {
         super.onCreate(savedInstanceState);
-        mList = EhApplication.getDownloadManager(getContext()).getLabelList();
+        mList = EhApplication.getDownloadManager(getContext2()).getLabelList();
     }
 
     @Override
@@ -97,7 +99,9 @@ public class DownloadLabelsScene extends ToolbarScene {
         TextView tip = (TextView) ViewUtils.$$(view, R.id.tip);
         mViewTransition = new ViewTransition(mRecyclerView, tip);
 
-        Drawable drawable = DrawableManager.getDrawable(getContext(), R.drawable.big_label);
+        Context context = getContext2();
+        AssertUtils.assertNotNull(context);
+        Drawable drawable = DrawableManager.getDrawable(context, R.drawable.big_label);
         drawable.setBounds(0, 0, drawable.getIntrinsicWidth(), drawable.getIntrinsicHeight());
         tip.setCompoundDrawables(null, drawable, null, null);
         tip.setText(R.string.no_download_label);
@@ -109,7 +113,7 @@ public class DownloadLabelsScene extends ToolbarScene {
         // drag & drop manager
         RecyclerViewDragDropManager dragDropManager = new RecyclerViewDragDropManager();
         dragDropManager.setDraggingItemShadowDrawable(
-                (NinePatchDrawable) getResources().getDrawable(R.drawable.shadow_8dp));
+                (NinePatchDrawable) context.getResources().getDrawable(R.drawable.shadow_8dp));
         // swipe manager
         RecyclerViewSwipeManager swipeManager = new RecyclerViewSwipeManager();
         RecyclerView.Adapter adapter = new LabelAdapter();
@@ -120,7 +124,7 @@ public class DownloadLabelsScene extends ToolbarScene {
         final GeneralItemAnimator animator = new SwipeDismissItemAnimator();
         animator.setSupportsChangeAnimations(false);
         mRecyclerView.hasFixedSize();
-        mRecyclerView.setLayoutManager(new LinearLayoutManager(getContext()));
+        mRecyclerView.setLayoutManager(new LinearLayoutManager(context));
         mRecyclerView.setAdapter(adapter);
         mRecyclerView.setItemAnimator(animator);
         guardManager.attachRecyclerView(mRecyclerView);
@@ -160,10 +164,15 @@ public class DownloadLabelsScene extends ToolbarScene {
 
     @Override
     public boolean onMenuItemClick(MenuItem item) {
+        Context context = getContext2();
+        if (null == context) {
+            return false;
+        }
+
         int id = item.getItemId();
         switch (id) {
             case R.id.action_add: {
-                EditTextDialogBuilder builder = new EditTextDialogBuilder(getContext(), null, getString(R.string.download_labels));
+                EditTextDialogBuilder builder = new EditTextDialogBuilder(context, null, getString(R.string.download_labels));
                 builder.setTitle(R.string.new_label_title);
                 builder.setPositiveButton(android.R.string.ok, null);
                 AlertDialog dialog = builder.show();
@@ -199,17 +208,22 @@ public class DownloadLabelsScene extends ToolbarScene {
 
         @Override
         public void onClick(View v) {
+            Context context = getContext2();
+            if (null == context) {
+                return;
+            }
+
             String text = mBuilder.getText();
             if (TextUtils.isEmpty(text)) {
                 mBuilder.setError(getString(R.string.label_text_is_empty));
             } else if (getString(R.string.default_download_label_name).equals(text)) {
                 mBuilder.setError(getString(R.string.label_text_is_invalid));
-            } else if (EhApplication.getDownloadManager(getContext()).containLabel(text)) {
+            } else if (EhApplication.getDownloadManager(context).containLabel(text)) {
                 mBuilder.setError(getString(R.string.label_text_exist));
             } else {
                 mBuilder.setError(null);
                 mDialog.dismiss();
-                EhApplication.getDownloadManager(getContext()).addLabel(text);
+                EhApplication.getDownloadManager(context).addLabel(text);
                 if (mAdapter != null && mList != null) {
                     mAdapter.notifyItemInserted(mList.size() - 1);
                 }
@@ -245,17 +259,22 @@ public class DownloadLabelsScene extends ToolbarScene {
 
         @Override
         public void onClick(View v) {
+            Context context = getContext2();
+            if (null == context) {
+                return;
+            }
+
             String text = mBuilder.getText();
             if (TextUtils.isEmpty(text)) {
                 mBuilder.setError(getString(R.string.label_text_is_empty));
             } else if (getString(R.string.default_download_label_name).equals(text)) {
                 mBuilder.setError(getString(R.string.label_text_is_invalid));
-            } else if (EhApplication.getDownloadManager(getContext()).containLabel(text)) {
+            } else if (EhApplication.getDownloadManager(context).containLabel(text)) {
                 mBuilder.setError(getString(R.string.label_text_exist));
             } else {
                 mBuilder.setError(null);
                 mDialog.dismiss();
-                EhApplication.getDownloadManager(getContext()).renameLabel(mOriginalLabel, text);
+                EhApplication.getDownloadManager(context).renameLabel(mOriginalLabel, text);
                 if (mAdapter != null) {
                     mAdapter.notifyItemChanged(mPosition);
                 }
@@ -282,7 +301,8 @@ public class DownloadLabelsScene extends ToolbarScene {
 
         @Override
         public void onClick(View v) {
-            if (mList == null || mRecyclerView == null) {
+            Context context = getContext2();
+            if (null == context || null == mList || null == mRecyclerView) {
                 return;
             }
 
@@ -294,7 +314,7 @@ public class DownloadLabelsScene extends ToolbarScene {
             if (label == v) {
                 DownloadLabel raw = mList.get(index);
                 EditTextDialogBuilder builder = new EditTextDialogBuilder(
-                        getContext(), raw.getLabel(), getString(R.string.download_labels));
+                        context, raw.getLabel(), getString(R.string.download_labels));
                 builder.setTitle(R.string.rename_label_title);
                 builder.setPositiveButton(android.R.string.ok, null);
                 AlertDialog dialog = builder.show();
@@ -312,10 +332,16 @@ public class DownloadLabelsScene extends ToolbarScene {
             implements DraggableItemAdapter<LabelHolder>,
             SwipeableItemAdapter<LabelHolder> {
 
+        private final LayoutInflater mInflater;
+
+        public LabelAdapter() {
+            mInflater = getLayoutInflater2();
+            AssertUtils.assertNotNull(mInflater);
+        }
+
         @Override
         public LabelHolder onCreateViewHolder(ViewGroup parent, int viewType) {
-            return new LabelHolder(getActivity().getLayoutInflater()
-                    .inflate(R.layout.item_label_list, parent, false));
+            return new LabelHolder(mInflater.inflate(R.layout.item_label_list, parent, false));
         }
 
         @Override
@@ -348,11 +374,12 @@ public class DownloadLabelsScene extends ToolbarScene {
 
         @Override
         public void onMoveItem(int fromPosition, int toPosition) {
-            if (fromPosition == toPosition) {
+            Context context = getContext2();
+            if (null == context || fromPosition == toPosition) {
                 return;
             }
 
-            EhApplication.getDownloadManager(getContext()).moveLabel(fromPosition, toPosition);
+            EhApplication.getDownloadManager(context).moveLabel(fromPosition, toPosition);
             if (mAdapter != null && mList != null) {
                 notifyItemMoved(fromPosition, toPosition);
             }
@@ -397,19 +424,20 @@ public class DownloadLabelsScene extends ToolbarScene {
         protected void onPerformAction() {
             super.onPerformAction();
 
+            final Context context = getContext2();
             final List<DownloadLabel> list = mList;
-            if (list == null || mPosition < 0 || mPosition >= list.size()) {
+            if (null == context || null == list || mPosition < 0 || mPosition >= list.size()) {
                 return;
             }
             final DownloadLabel label = list.get(mPosition);
 
-            new AlertDialog.Builder(getContext())
+            new AlertDialog.Builder(context)
                     .setTitle(R.string.delete_label_title)
                     .setMessage(getString(R.string.delete_label_message, label.getLabel()))
                     .setPositiveButton(android.R.string.ok, new DialogInterface.OnClickListener() {
                         @Override
                         public void onClick(DialogInterface dialog, int which) {
-                            EhApplication.getDownloadManager(getContext()).deleteLabel(label.getLabel());
+                            EhApplication.getDownloadManager(context).deleteLabel(label.getLabel());
                         }
                     })
                     .setOnDismissListener(new DialogInterface.OnDismissListener() {

app/src/main/java/com/hippo/ehviewer/ui/scene/DownloadsScene.java

@@ -18,8 +18,11 @@ package com.hippo.ehviewer.ui.scene;
 
 import android.annotation.SuppressLint;
 import android.annotation.TargetApi;
+import android.app.Activity;
+import android.content.Context;
 import android.content.DialogInterface;
 import android.content.Intent;
+import android.content.res.Resources;
 import android.graphics.Point;
 import android.graphics.drawable.Drawable;
 import android.os.AsyncTask;
@@ -34,6 +37,7 @@ import android.support.v7.widget.LinearLayoutManager;
 import android.support.v7.widget.RecyclerView;
 import android.support.v7.widget.SimpleItemAnimator;
 import android.support.v7.widget.Toolbar;
+import android.util.Log;
 import android.util.SparseBooleanArray;
 import android.view.Display;
 import android.view.Gravity;
@@ -68,6 +72,7 @@ import com.hippo.ehviewer.download.DownloadManager;
 import com.hippo.ehviewer.download.DownloadService;
 import com.hippo.ehviewer.spider.SpiderDen;
 import com.hippo.ehviewer.ui.GalleryActivity;
+import com.hippo.ehviewer.ui.MainActivity;
 import com.hippo.ehviewer.widget.SimpleRatingView;
 import com.hippo.rippleold.RippleSalon;
 import com.hippo.scene.Announcer;
@@ -77,6 +82,7 @@ import com.hippo.util.DrawableManager;
 import com.hippo.view.ViewTransition;
 import com.hippo.widget.FabLayout;
 import com.hippo.widget.LoadImageView;
+import com.hippo.yorozuya.AssertUtils;
 import com.hippo.yorozuya.FileUtils;
 import com.hippo.yorozuya.LongList;
 import com.hippo.yorozuya.ObjectUtils;
@@ -94,6 +100,8 @@ public class DownloadsScene extends ToolbarScene
         EasyRecyclerView.OnItemLongClickListener,
         FabLayout.OnClickFabListener, FastScroller.OnDragHandlerListener {
 
+    private static final String TAG = DownloadsScene.class.getSimpleName();
+
     public static final String KEY_ACTION = "action";
     private static final String KEY_LABEL = "label";
 
@@ -145,7 +153,9 @@ public class DownloadsScene extends ToolbarScene
 
         handleArguments(getArguments());
 
-        mDownloadManager = EhApplication.getDownloadManager(getContext());
+        Context context = getContext2();
+        AssertUtils.assertNotNull(context);
+        mDownloadManager = EhApplication.getDownloadManager(context);
         mDownloadManager.addDownloadInfoListener(this);
 
         if (savedInstanceState == null) {
@@ -162,11 +172,19 @@ public class DownloadsScene extends ToolbarScene
 
         DownloadManager manager = mDownloadManager;
         if (null == manager) {
-            manager = EhApplication.getDownloadManager(getContext());
+            Context context = getContext2();
+            if (null != context) {
+                manager = EhApplication.getDownloadManager(context);
+            }
         } else {
             mDownloadManager = null;
         }
-        manager.removeDownloadInfoListener(this);
+
+        if (null != manager) {
+            manager.removeDownloadInfoListener(this);
+        } else {
+            Log.e(TAG, "Can't removeDownloadInfoListener");
+        }
     }
 
     private void updateForLabel() {
@@ -226,14 +244,17 @@ public class DownloadsScene extends ToolbarScene
         TextView tip = (TextView) ViewUtils.$$(view, R.id.tip);
         mViewTransition = new ViewTransition(content, tip);
 
-        Drawable drawable = DrawableManager.getDrawable(getContext(), R.drawable.big_download);
+        Context context = getContext2();
+        AssertUtils.assertNotNull(content);
+
+        Drawable drawable = DrawableManager.getDrawable(context, R.drawable.big_download);
         drawable.setBounds(0, 0, drawable.getIntrinsicWidth(), drawable.getIntrinsicHeight());
         tip.setCompoundDrawables(null, drawable, null, null);
 
         mAdapter = new DownloadAdapter();
         mAdapter.setHasStableIds(true);
         mRecyclerView.setAdapter(mAdapter);
-        mLayoutManager = new LinearLayoutManager(getContext());
+        mLayoutManager = new LinearLayoutManager(context);
         mRecyclerView.setLayoutManager(mLayoutManager);
         mRecyclerView.setSelector(RippleSalon.generateRippleDrawable(false));
         mRecyclerView.setDrawSelectorOnTop(true);
@@ -248,13 +269,13 @@ public class DownloadsScene extends ToolbarScene
         if (itemAnimator instanceof SimpleItemAnimator) {
             ((SimpleItemAnimator) itemAnimator).setSupportsChangeAnimations(false);
         }
-        int paddingH = getResources().getDimensionPixelOffset(R.dimen.list_content_margin_h);
-        int paddingV = getResources().getDimensionPixelOffset(R.dimen.list_content_margin_v);
+        int paddingH = context.getResources().getDimensionPixelOffset(R.dimen.list_content_margin_h);
+        int paddingV = context.getResources().getDimensionPixelOffset(R.dimen.list_content_margin_v);
         mRecyclerView.setPadding(paddingV, paddingH, paddingV, paddingH);
 
         fastScroller.attachToRecyclerView(mRecyclerView);
         HandlerDrawable handlerDrawable = new HandlerDrawable();
-        handlerDrawable.setColor(ResourcesUtils.getAttrColor(getContext(), R.attr.colorAccent));
+        handlerDrawable.setColor(ResourcesUtils.getAttrColor(context, R.attr.colorAccent));
         fastScroller.setHandlerDrawable(handlerDrawable);
         fastScroller.setOnDragHandlerListener(this);
 
@@ -284,7 +305,8 @@ public class DownloadsScene extends ToolbarScene
     }
 
     private void guideDownloadThumb() {
-        if (!Settings.getGuideDownloadThumb() || null == mLayoutManager || null == mRecyclerView) {
+        MainActivity activity = getActivity2();
+        if (null == activity || !Settings.getGuideDownloadThumb() || null == mLayoutManager || null == mRecyclerView) {
             guideDownloadLabels();
             return;
         }
@@ -299,7 +321,7 @@ public class DownloadsScene extends ToolbarScene
             return;
         }
 
-        new ShowcaseView.Builder(getActivity())
+        new ShowcaseView.Builder(activity)
                 .withMaterialShowcase()
                 .setStyle(R.style.Guide)
                 .setTarget(new ViewTarget(((DownloadHolder) holder).thumb))
@@ -318,15 +340,16 @@ public class DownloadsScene extends ToolbarScene
     }
 
     private void guideDownloadLabels() {
-        if (!Settings.getGuideDownloadLabels()) {
+        MainActivity activity = getActivity2();
+        if (null == activity || !Settings.getGuideDownloadLabels()) {
             return;
         }
 
-        Display display = getActivity().getWindowManager().getDefaultDisplay();
+        Display display = activity.getWindowManager().getDefaultDisplay();
         Point point = new Point();
         display.getSize(point);
 
-        new ShowcaseView.Builder(getActivity())
+        new ShowcaseView.Builder(activity)
                 .withMaterialShowcase()
                 .setStyle(R.style.Guide)
                 .setTarget(new PointTarget(point.x, point.y / 3))
@@ -375,16 +398,17 @@ public class DownloadsScene extends ToolbarScene
     @Override
     public boolean onMenuItemClick(MenuItem item) {
         // Skip when in choice mode
-        if (mRecyclerView == null || mRecyclerView.isInCustomChoice()) {
+        Activity activity = getActivity2();
+        if (null == activity || null == mRecyclerView || mRecyclerView.isInCustomChoice()) {
             return false;
         }
 
         int id = item.getItemId();
         switch (id) {
             case R.id.action_start_all: {
-                Intent intent = new Intent(getActivity(), DownloadService.class);
+                Intent intent = new Intent(activity, DownloadService.class);
                 intent.setAction(DownloadService.ACTION_START_ALL);
-                getActivity().startService(intent);
+                activity.startService(intent);
                 return true;
             }
             case R.id.action_stop_all: {
@@ -412,6 +436,9 @@ public class DownloadsScene extends ToolbarScene
             @Nullable ViewGroup container, @Nullable Bundle savedInstanceState) {
         View view = inflater.inflate(R.layout.drawer_list, container, false);
 
+        final Context context = getContext2();
+        AssertUtils.assertNotNull(context);
+
         Toolbar toolbar = (Toolbar) view.findViewById(R.id.toolbar);
         toolbar.setTitle(R.string.download_labels);
         toolbar.inflateMenu(R.menu.drawer_download);
@@ -436,7 +463,7 @@ public class DownloadsScene extends ToolbarScene
                         for (int i = 0, n = list.size(); i < n; i++) {
                             items[i + 2] = list.get(i).getLabel();
                         }
-                        new AlertDialog.Builder(getContext())
+                        new AlertDialog.Builder(context)
                                 .setTitle(R.string.default_download_label)
                                 .setItems(items, new DialogInterface.OnClickListener() {
                                     @Override
@@ -461,7 +488,7 @@ public class DownloadsScene extends ToolbarScene
             }
         });
 
-        List<DownloadLabel> list = EhApplication.getDownloadManager(getContext()).getLabelList();
+        List<DownloadLabel> list = EhApplication.getDownloadManager(context).getLabelList();
         final List<String> labels = new ArrayList<>(list.size() + 1);
         // Add default label name
         labels.add(getString(R.string.default_download_label_name));
@@ -471,7 +498,7 @@ public class DownloadsScene extends ToolbarScene
 
         // TODO handle download label items update
         ListView listView = (ListView) view.findViewById(R.id.list_view);
-        listView.setAdapter(new ArrayAdapter<>(getContext(), R.layout.item_simple_list, labels));
+        listView.setAdapter(new ArrayAdapter<>(context, R.layout.item_simple_list, labels));
         listView.setOnItemClickListener(new AdapterView.OnItemClickListener() {
             @Override
             public void onItemClick(AdapterView<?> parent, View view, int position, long id) {
@@ -518,8 +545,9 @@ public class DownloadsScene extends ToolbarScene
 
     @Override
     public boolean onItemClick(EasyRecyclerView parent, View view, int position, long id) {
+        Activity activity = getActivity2();
         EasyRecyclerView recyclerView = mRecyclerView;
-        if (recyclerView == null) {
+        if (null == activity || null == recyclerView) {
             return false;
         }
 
@@ -535,7 +563,7 @@ public class DownloadsScene extends ToolbarScene
                 return false;
             }
 
-            Intent intent = new Intent(getActivity(), GalleryActivity.class);
+            Intent intent = new Intent(activity, GalleryActivity.class);
             intent.setAction(GalleryActivity.ACTION_EH);
             intent.putExtra(GalleryActivity.KEY_GALLERY_INFO, list.get(position));
             startActivity(intent);
@@ -567,8 +595,10 @@ public class DownloadsScene extends ToolbarScene
 
     @Override
     public void onClickSecondaryFab(FabLayout view, FloatingActionButton fab, int position) {
+        Context context = getContext2();
+        Activity activity = getActivity2();
         EasyRecyclerView recyclerView = mRecyclerView;
-        if (recyclerView == null) {
+        if (null == context || null == activity || null == recyclerView) {
             return;
         }
 
@@ -606,10 +636,10 @@ public class DownloadsScene extends ToolbarScene
 
             switch (position) {
                 case 1: { // Start
-                    Intent intent = new Intent(getActivity(), DownloadService.class);
+                    Intent intent = new Intent(activity, DownloadService.class);
                     intent.setAction(DownloadService.ACTION_START_RANGE);
                     intent.putExtra(DownloadService.KEY_GID_LIST, gidList);
-                    getActivity().startService(intent);
+                    activity.startService(intent);
                     // Cancel check mode
                     recyclerView.outOfCustomChoiceMode();
                     break;
@@ -623,7 +653,7 @@ public class DownloadsScene extends ToolbarScene
                     break;
                 }
                 case 3: { // Delete
-                    CheckBoxDialogBuilder builder = new CheckBoxDialogBuilder(getContext(),
+                    CheckBoxDialogBuilder builder = new CheckBoxDialogBuilder(context,
                             getString(R.string.download_remove_dialog_message_2, gidList.size()),
                             getString(R.string.download_remove_dialog_check_text),
                             Settings.getRemoveImageFiles());
@@ -635,7 +665,7 @@ public class DownloadsScene extends ToolbarScene
                     break;
                 }
                 case 4: {// Move
-                    List<DownloadLabel> labelRawList = EhApplication.getDownloadManager(getContext()).getLabelList();
+                    List<DownloadLabel> labelRawList = EhApplication.getDownloadManager(context).getLabelList();
                     List<String> labelList = new ArrayList<>(labelRawList.size() + 1);
                     labelList.add(getString(R.string.default_download_label_name));
                     for (int i = 0, n = labelRawList.size(); i < n; i++) {
@@ -645,7 +675,7 @@ public class DownloadsScene extends ToolbarScene
 
                     MoveDialogHelper helper = new MoveDialogHelper(labels, downloadInfoList);
 
-                    new AlertDialog.Builder(getContext())
+                    new AlertDialog.Builder(context)
                             .setTitle(R.string.download_move_dialog_title)
                             .setItems(labels, helper)
                             .show();
@@ -728,12 +758,17 @@ public class DownloadsScene extends ToolbarScene
     }
 
     private void bindForState(DownloadHolder holder, DownloadInfo info) {
+        Resources resources = getResources2();
+        if (null == resources) {
+            return;
+        }
+
         switch (info.state) {
             case DownloadInfo.STATE_NONE:
-                bindState(holder, info, getContext().getString(R.string.download_state_none));
+                bindState(holder, info, resources.getString(R.string.download_state_none));
                 break;
             case DownloadInfo.STATE_WAIT:
-                bindState(holder, info, getContext().getString(R.string.download_state_wait));
+                bindState(holder, info, resources.getString(R.string.download_state_wait));
                 break;
             case DownloadInfo.STATE_DOWNLOAD:
                 bindProgress(holder, info);
@@ -741,14 +776,14 @@ public class DownloadsScene extends ToolbarScene
             case DownloadInfo.STATE_FAILED:
                 String text;
                 if (info.legacy <= 0) {
-                    text = getContext().getString(R.string.download_state_failed);
+                    text = resources.getString(R.string.download_state_failed);
                 } else {
-                    text = getContext().getString(R.string.download_state_failed_2, info.legacy);
+                    text = resources.getString(R.string.download_state_failed_2, info.legacy);
                 }
                 bindState(holder, info, text);
                 break;
             case DownloadInfo.STATE_FINISH:
-                bindState(holder, info, getContext().getString(R.string.download_state_finish));
+                bindState(holder, info, resources.getString(R.string.download_state_finish));
                 break;
         }
     }
@@ -912,7 +947,11 @@ public class DownloadsScene extends ToolbarScene
         @Override
         public void onClick(DialogInterface dialog, int which) {
             // Cancel check mode
-            if (mRecyclerView != null) {
+            Context context = getContext2();
+            if (null == context) {
+                return;
+            }
+            if (null != mRecyclerView) {
                 mRecyclerView.outOfCustomChoiceMode();
             }
 
@@ -922,7 +961,7 @@ public class DownloadsScene extends ToolbarScene
             } else {
                 label = mLabels[which];
             }
-            EhApplication.getDownloadManager(getContext()).changeLabel(mDownloadInfoList, label);
+            EhApplication.getDownloadManager(context).changeLabel(mDownloadInfoList, label);
         }
     }
 
@@ -969,8 +1008,10 @@ public class DownloadsScene extends ToolbarScene
 
         @Override
         public void onClick(View v) {
+            Context context = getContext2();
+            Activity activity = getActivity2();
             EasyRecyclerView recyclerView = mRecyclerView;
-            if (recyclerView == null || recyclerView.isInCustomChoice()) {
+            if (null == context || null == activity || null == recyclerView || recyclerView.isInCustomChoice()) {
                 return;
             }
             List<DownloadInfo> list = mList;
@@ -993,17 +1034,17 @@ public class DownloadsScene extends ToolbarScene
                 }
                 startScene(announcer);
             } else if (start == v) {
-                Intent intent = new Intent(getActivity(), DownloadService.class);
+                Intent intent = new Intent(activity, DownloadService.class);
                 intent.setAction(DownloadService.ACTION_START);
                 intent.putExtra(DownloadService.KEY_GALLERY_INFO, list.get(index));
-                getActivity().startService(intent);
+                activity.startService(intent);
             } else if (stop == v) {
                 if (null != mDownloadManager) {
                     mDownloadManager.stopDownload(list.get(index).gid);
                 }
             } else if (delete == v) {
                 GalleryInfo galleryInfo = list.get(index);
-                CheckBoxDialogBuilder builder = new CheckBoxDialogBuilder(getContext(),
+                CheckBoxDialogBuilder builder = new CheckBoxDialogBuilder(context,
                         getString(R.string.download_remove_dialog_message, EhUtils.getSuitableTitle(galleryInfo)),
                         getString(R.string.download_remove_dialog_check_text),
                         Settings.getRemoveImageFiles());
@@ -1017,6 +1058,13 @@ public class DownloadsScene extends ToolbarScene
 
     private class DownloadAdapter extends RecyclerView.Adapter<DownloadHolder> {
 
+        private final LayoutInflater mInflater;
+
+        public DownloadAdapter() {
+            mInflater = getLayoutInflater2();
+            AssertUtils.assertNotNull(mInflater);
+        }
+
         @Override
         public long getItemId(int position) {
             if (mList == null || position < 0 || position >= mList.size()) {
@@ -1027,7 +1075,7 @@ public class DownloadsScene extends ToolbarScene
 
         @Override
         public DownloadHolder onCreateViewHolder(ViewGroup parent, int viewType) {
-            return new DownloadHolder(getActivity().getLayoutInflater().inflate(R.layout.item_download, parent, false));
+            return new DownloadHolder(mInflater.inflate(R.layout.item_download, parent, false));
         }
 
         @TargetApi(Build.VERSION_CODES.LOLLIPOP)

app/src/main/java/com/hippo/ehviewer/ui/scene/FavoritesScene.java

@@ -16,6 +16,7 @@
 
 package com.hippo.ehviewer.ui.scene;
 
+import android.app.Activity;
 import android.content.Context;
 import android.content.DialogInterface;
 import android.content.res.Resources;
@@ -61,6 +62,7 @@ import com.hippo.ehviewer.client.data.FavListUrlBuilder;
 import com.hippo.ehviewer.client.data.GalleryInfo;
 import com.hippo.ehviewer.client.exception.NotFoundException;
 import com.hippo.ehviewer.client.parser.FavoritesParser;
+import com.hippo.ehviewer.ui.MainActivity;
 import com.hippo.ehviewer.ui.annotation.DrawerLifeCircle;
 import com.hippo.ehviewer.ui.annotation.ViewLifeCircle;
 import com.hippo.ehviewer.ui.annotation.WholeLifeCircle;
@@ -68,7 +70,6 @@ import com.hippo.ehviewer.widget.SearchBar;
 import com.hippo.rippleold.RippleSalon;
 import com.hippo.scene.Announcer;
 import com.hippo.scene.SceneFragment;
-import com.hippo.scene.StageActivity;
 import com.hippo.util.ApiHelper;
 import com.hippo.util.DrawableManager;
 import com.hippo.widget.ContentLayout;
@@ -76,6 +77,7 @@ import com.hippo.widget.FabLayout;
 import com.hippo.widget.SearchBarMover;
 import com.hippo.widget.recyclerview.GridAutoSpanLayoutManager;
 import com.hippo.widget.refreshlayout.RefreshLayout;
+import com.hippo.yorozuya.AssertUtils;
 import com.hippo.yorozuya.ObjectUtils;
 import com.hippo.yorozuya.SimpleHandler;
 import com.hippo.yorozuya.ViewUtils;
@@ -181,7 +183,9 @@ public class FavoritesScene extends BaseScene implements
     public void onCreate(@Nullable Bundle savedInstanceState) {
         super.onCreate(savedInstanceState);
 
-        mClient = EhApplication.getEhClient(getContext());
+        Context context = getContext2();
+        AssertUtils.assertNotNull(context);
+        mClient = EhApplication.getEhClient(context);
         mFavCatArray = Settings.getFavCat();
 
         if (savedInstanceState == null) {
@@ -248,14 +252,16 @@ public class FavoritesScene extends BaseScene implements
         mSearchBar = (SearchBar) ViewUtils.$$(view, R.id.search_bar);
         mFabLayout = (FabLayout) ViewUtils.$$(view, R.id.fab_layout);
 
-        Resources resources = getResources();
+        Context context = getContext2();
+        AssertUtils.assertNotNull(context);
+        Resources resources = context.getResources();
         int paddingTopSB = resources.getDimensionPixelOffset(R.dimen.list_padding_top_search_bar);
 
         mHelper = new FavoritesHelper();
         contentLayout.setHelper(mHelper);
         contentLayout.getFastScroller().setOnDragHandlerListener(this);
 
-        GridAutoSpanLayoutManager layoutManager = new GridAutoSpanLayoutManager(getContext(), 0);
+        GridAutoSpanLayoutManager layoutManager = new GridAutoSpanLayoutManager(context, 0);
         mRecyclerView.setLayoutManager(layoutManager);
         mRecyclerView.setSelector(RippleSalon.generateRippleDrawable(false));
         mRecyclerView.setDrawSelectorOnTop(true);
@@ -265,8 +271,8 @@ public class FavoritesScene extends BaseScene implements
         mRecyclerView.setOnItemLongClickListener(this);
         mRecyclerView.setChoiceMode(EasyRecyclerView.CHOICE_MODE_MULTIPLE_CUSTOM);
         mRecyclerView.setCustomCheckedListener(this);
-        mAdapter = new FavoritesAdapter(LayoutInflater.from(getContext()),
-                getContext(), mRecyclerView, layoutManager, Settings.getListMode());
+        mAdapter = new FavoritesAdapter(getLayoutInflater2(),
+                getResources2(), mRecyclerView, layoutManager, Settings.getListMode());
         mRecyclerView.setAdapter(mAdapter);
         mAdapter.register();
         mRecyclerView.setPadding(mRecyclerView.getPaddingLeft(), mRecyclerView.getPaddingTop() + paddingTopSB,
@@ -277,9 +283,9 @@ public class FavoritesScene extends BaseScene implements
 
         refreshLayout.setHeaderTranslationY(paddingTopSB);
 
-        mLeftDrawable = new DrawerArrowDrawable(getContext());
+        mLeftDrawable = new DrawerArrowDrawable(context);
         mSearchBar.setLeftDrawable(mLeftDrawable);
-        mSearchBar.setRightDrawable(DrawableManager.getDrawable(getContext(), R.drawable.v_magnify_x24));
+        mSearchBar.setRightDrawable(DrawableManager.getDrawable(context, R.drawable.v_magnify_x24));
         mSearchBar.setHelper(this);
         mSearchBar.setAllowEmptySearch(false);
         updateSearchBar();
@@ -308,15 +314,16 @@ public class FavoritesScene extends BaseScene implements
     }
 
     private void guideCollections() {
-        if (!Settings.getGuideCollections()) {
+        Activity activity = getActivity2();
+        if (null == activity || !Settings.getGuideCollections()) {
             return;
         }
 
-        Display display = getActivity().getWindowManager().getDefaultDisplay();
+        Display display = activity.getWindowManager().getDefaultDisplay();
         Point point = new Point();
         display.getSize(point);
 
-        new ShowcaseView.Builder(getActivity())
+        new ShowcaseView.Builder(activity)
                 .withMaterialShowcase()
                 .setStyle(R.style.Guide)
                 .setTarget(new PointTarget(point.x, point.y / 3))
@@ -337,7 +344,8 @@ public class FavoritesScene extends BaseScene implements
     // keyword of mUrlBuilder, fav cat of mUrlBuilder, mFavCatArray.
     // They changed, call it
     private void updateSearchBar() {
-        if (mUrlBuilder == null || mSearchBar == null || mFavCatArray == null) {
+        Context context = getContext2();
+        if (null == context || null == mUrlBuilder || null == mSearchBar || null == mFavCatArray) {
             return;
         }
 
@@ -364,7 +372,7 @@ public class FavoritesScene extends BaseScene implements
 
         // Update hint
         if (!ObjectUtils.equal(favCatName, mOldFavCat)) {
-            Drawable searchImage = DrawableManager.getDrawable(getContext(), R.drawable.v_magnify_x24);
+            Drawable searchImage = DrawableManager.getDrawable(context, R.drawable.v_magnify_x24);
             SpannableStringBuilder ssb = new SpannableStringBuilder("   ");
             ssb.append(getString(R.string.favorites_search_bar_hint, favCatName));
             int textSize = (int) (mSearchBar.getEditTextTextSize() * 1.25);
@@ -409,7 +417,8 @@ public class FavoritesScene extends BaseScene implements
     }
 
     private void showFavoritesInfoDialog() {
-        if (mFavCatArray == null || mFavCountArray == null) {
+        Context context = getContext2();
+        if (null == context || null == mFavCatArray || null == mFavCountArray) {
             return;
         }
 
@@ -419,7 +428,7 @@ public class FavoritesScene extends BaseScene implements
             sb.append(mFavCatArray[i]).append(": ").append(mFavCountArray[i]).append("\n");
         }
 
-        new AlertDialog.Builder(getContext())
+        new AlertDialog.Builder(context)
                 .setTitle(R.string.favorites_info)
                 .setMessage(sb.toString())
                 .show();
@@ -432,6 +441,9 @@ public class FavoritesScene extends BaseScene implements
         Toolbar toolbar = (Toolbar) ViewUtils.$$(view, R.id.toolbar);
         ListView listView = (ListView) view.findViewById(R.id.list_view);
 
+        final Context context = getContext2();
+        AssertUtils.assertNotNull(context);
+
         toolbar.setTitle(R.string.collections);
         toolbar.inflateMenu(R.menu.drawer_favorites);
         toolbar.setOnMenuItemClickListener(new Toolbar.OnMenuItemClickListener() {
@@ -448,7 +460,7 @@ public class FavoritesScene extends BaseScene implements
                         items[1] = getString(R.string.local_favorites);
                         String[] favCat = Settings.getFavCat();
                         System.arraycopy(favCat, 0, items, 2, 10);
-                        new AlertDialog.Builder(getContext())
+                        new AlertDialog.Builder(context)
                                 .setTitle(R.string.default_favorites_collection)
                                 .setItems(items, new DialogInterface.OnClickListener() {
                                     @Override
@@ -468,7 +480,7 @@ public class FavoritesScene extends BaseScene implements
         if (mFavCatArray != null) {
             Collections.addAll(mDrawerList, mFavCatArray);
         }
-        mDrawerAdapter = new ArrayAdapter<>(getContext(), R.layout.item_simple_list, mDrawerList);
+        mDrawerAdapter = new ArrayAdapter<>(context, R.layout.item_simple_list, mDrawerList);
         listView.setAdapter(mDrawerAdapter);
         listView.setOnItemClickListener(this);
 
@@ -656,7 +668,8 @@ public class FavoritesScene extends BaseScene implements
     @Override
     @Implemented(FabLayout.OnClickFabListener.class)
     public void onClickSecondaryFab(FabLayout view, FloatingActionButton fab, int position) {
-        if (mRecyclerView == null || mHelper == null || !mRecyclerView.isInCustomChoice()) {
+        Context context = getContext2();
+        if (null == context || null == mRecyclerView || null == mHelper || !mRecyclerView.isInCustomChoice()) {
             return;
         }
 
@@ -671,7 +684,7 @@ public class FavoritesScene extends BaseScene implements
         switch (position) {
             case 0: { // Delete
                 DeleteDialogHelper helper = new DeleteDialogHelper();
-                new AlertDialog.Builder(getContext())
+                new AlertDialog.Builder(context)
                         .setTitle(R.string.delete_favorites_dialog_title)
                         .setMessage(getString(R.string.delete_favorites_dialog_message, mModifyGiList.size()))
                         .setPositiveButton(android.R.string.ok, helper)
@@ -685,7 +698,7 @@ public class FavoritesScene extends BaseScene implements
                 String[] array = new String[11];
                 array[0] = getString(R.string.local_favorites);
                 System.arraycopy(Settings.getFavCat(), 0, array, 1, 10);
-                new AlertDialog.Builder(getContext())
+                new AlertDialog.Builder(context)
                         .setTitle(R.string.move_favorites_dialog_title)
                         .setItems(array, helper)
                         .setOnCancelListener(helper)
@@ -930,9 +943,9 @@ public class FavoritesScene extends BaseScene implements
 
     private class FavoritesAdapter extends GalleryAdapter {
 
-        public FavoritesAdapter(LayoutInflater inflater, Context context,
+        public FavoritesAdapter(LayoutInflater inflater, Resources resources,
                 RecyclerView recyclerView, GridAutoSpanLayoutManager layoutManager, int type) {
-            super(inflater, context, recyclerView, layoutManager, type);
+            super(inflater, resources, recyclerView, layoutManager, type);
         }
 
         @Override
@@ -951,7 +964,8 @@ public class FavoritesScene extends BaseScene implements
 
         @Override
         protected void getPageData(final int taskId, int type, int page) {
-            if (mUrlBuilder == null || mClient == null) {
+            MainActivity activity = getActivity2();
+            if (null == activity || null == mUrlBuilder || null == mClient ) {
                 return;
             }
 
@@ -973,7 +987,7 @@ public class FavoritesScene extends BaseScene implements
                     EhRequest request = new EhRequest();
                     request.setMethod(EhClient.METHOD_ADD_FAVORITES_RANGE);
                     request.setCallback(new AddFavoritesListener(getContext(),
-                            ((StageActivity) getActivity()).getStageId(), getTag(),
+                            activity.getStageId(), getTag(),
                             taskId, mUrlBuilder.getKeyword()));
                     request.setArgs(gidArray, tokenArray, mModifyFavCat);
                     mClient.execute(request);
@@ -996,7 +1010,7 @@ public class FavoritesScene extends BaseScene implements
                     EhRequest request = new EhRequest();
                     request.setMethod(EhClient.METHOD_MODIFY_FAVORITES);
                     request.setCallback(new GetFavoritesListener(getContext(),
-                            ((StageActivity) getActivity()).getStageId(), getTag(),
+                            activity.getStageId(), getTag(),
                             taskId, local, mUrlBuilder.getKeyword()));
                     request.setArgs(url, gidArray, mModifyFavCat, Settings.getShowJpnTitle());
                     mClient.execute(request);
@@ -1015,7 +1029,7 @@ public class FavoritesScene extends BaseScene implements
                 EhRequest request = new EhRequest();
                 request.setMethod(EhClient.METHOD_GET_FAVORITES);
                 request.setCallback(new GetFavoritesListener(getContext(),
-                        ((StageActivity) getActivity()).getStageId(), getTag(),
+                        activity.getStageId(), getTag(),
                         taskId, false, mUrlBuilder.getKeyword()));
                 request.setArgs(url, Settings.getShowJpnTitle());
                 mClient.execute(request);
@@ -1032,7 +1046,7 @@ public class FavoritesScene extends BaseScene implements
 
         @Override
         protected Context getContext() {
-            return FavoritesScene.this.getContext();
+            return FavoritesScene.this.getContext2();
         }
 
         @Override

app/src/main/java/com/hippo/ehviewer/ui/scene/GalleryAdapter.java

@@ -17,11 +17,11 @@
 package com.hippo.ehviewer.ui.scene;
 
 import android.annotation.TargetApi;
-import android.content.Context;
 import android.content.res.Resources;
 import android.graphics.drawable.Drawable;
 import android.os.Build;
 import android.support.annotation.IntDef;
+import android.support.annotation.NonNull;
 import android.support.annotation.Nullable;
 import android.support.v7.widget.RecyclerView;
 import android.view.LayoutInflater;
@@ -55,18 +55,16 @@ abstract class GalleryAdapter extends RecyclerView.Adapter<GalleryHolder> implem
     public static final int TYPE_GRID = 1;
 
     private final LayoutInflater mInflater;
-    private final Context mContext;
     private final Resources mResources;
     private final RecyclerView mRecyclerView;
     private final GridAutoSpanLayoutManager mLayoutManager;
     private RecyclerView.ItemDecoration mGirdDecoration;
     private int mType = TYPE_INVALID;
 
-    public GalleryAdapter(LayoutInflater inflater, Context context,
-            RecyclerView recyclerView, GridAutoSpanLayoutManager layoutManager, int type) {
+    public GalleryAdapter(@NonNull LayoutInflater inflater, @NonNull Resources resources,
+            @NonNull RecyclerView recyclerView, @NonNull GridAutoSpanLayoutManager layoutManager, int type) {
         mInflater = inflater;
-        mContext = context;
-        mResources = context.getResources();
+        mResources = resources;
         mRecyclerView = recyclerView;
         mLayoutManager = layoutManager;
 

app/src/main/java/com/hippo/ehviewer/ui/scene/GalleryCommentsScene.java

@@ -18,7 +18,9 @@ package com.hippo.ehviewer.ui.scene;
 
 import android.animation.Animator;
 import android.annotation.TargetApi;
+import android.app.Activity;
 import android.content.Context;
+import android.content.res.Resources;
 import android.graphics.drawable.Drawable;
 import android.os.Build;
 import android.os.Bundle;
@@ -48,18 +50,18 @@ import com.hippo.ehviewer.client.EhClient;
 import com.hippo.ehviewer.client.EhRequest;
 import com.hippo.ehviewer.client.EhUrl;
 import com.hippo.ehviewer.client.data.GalleryComment;
+import com.hippo.ehviewer.ui.MainActivity;
 import com.hippo.rippleold.RippleSalon;
 import com.hippo.scene.SceneFragment;
-import com.hippo.scene.StageActivity;
 import com.hippo.text.Html;
 import com.hippo.text.URLImageGetter;
-import com.hippo.util.ActivityHelper;
 import com.hippo.util.DrawableManager;
 import com.hippo.util.ReadableTime;
 import com.hippo.util.TextUrl;
 import com.hippo.view.ViewTransition;
 import com.hippo.widget.LinkifyTextView;
 import com.hippo.yorozuya.AnimationUtils;
+import com.hippo.yorozuya.AssertUtils;
 import com.hippo.yorozuya.LayoutUtils;
 import com.hippo.yorozuya.SimpleAnimatorListener;
 import com.hippo.yorozuya.ViewUtils;
@@ -143,19 +145,22 @@ public final class GalleryCommentsScene extends ToolbarScene
         mEditText = (EditText) ViewUtils.$$(mEditPanel, R.id.edit_text);
         mFab = (FloatingActionButton) ViewUtils.$$(view, R.id.fab);
 
-        int paddingBottomFab = getResources().getDimensionPixelOffset(R.dimen.list_padding_bottom_fab);
+        Context context = getContext2();
+        AssertUtils.assertNotNull(context);
+        Resources resources = context.getResources();
+        int paddingBottomFab = resources.getDimensionPixelOffset(R.dimen.list_padding_bottom_fab);
 
-        Drawable drawable = DrawableManager.getDrawable(getContext(), R.drawable.big_weird_face);
+        Drawable drawable = DrawableManager.getDrawable(context, R.drawable.big_weird_face);
         drawable.setBounds(0, 0, drawable.getIntrinsicWidth(), drawable.getIntrinsicHeight());
         tip.setCompoundDrawables(null, drawable, null, null);
 
         mAdapter = new CommentAdapter();
         recyclerView.setAdapter(mAdapter);
-        recyclerView.setLayoutManager(new LinearLayoutManager(getContext(),
+        recyclerView.setLayoutManager(new LinearLayoutManager(context,
                 LinearLayoutManager.VERTICAL, false));
         LinearDividerItemDecoration decoration = new LinearDividerItemDecoration(
-                LinearDividerItemDecoration.VERTICAL, getResources().getColor(R.color.divider),
-                LayoutUtils.dp2pix(getContext(), 1));
+                LinearDividerItemDecoration.VERTICAL, context.getResources().getColor(R.color.divider),
+                LayoutUtils.dp2pix(context, 1));
         decoration.setShowLastDivider(true);
         recyclerView.addItemDecoration(decoration);
         recyclerView.setSelector(RippleSalon.generateRippleDrawable(false));
@@ -200,6 +205,11 @@ public final class GalleryCommentsScene extends ToolbarScene
 
     @Override
     public boolean onItemClick(EasyRecyclerView parent, View view, int position, long id) {
+        Activity activity = getActivity2();
+        if (null == activity) {
+            return false;
+        }
+
         RecyclerView.ViewHolder holder = parent.getChildViewHolder(view);
         if (holder instanceof CommentHolder) {
             CommentHolder commentHolder = (CommentHolder) holder;
@@ -207,7 +217,7 @@ public final class GalleryCommentsScene extends ToolbarScene
             commentHolder.comment.clearCurrentSpan();
 
             if (span instanceof URLSpan) {
-                UrlOpener.openUrl(getActivity(), ((URLSpan) span).getURL(), true, true);
+                UrlOpener.openUrl(activity, ((URLSpan) span).getURL(), true, true);
                 return true;
             }
         }
@@ -322,6 +332,12 @@ public final class GalleryCommentsScene extends ToolbarScene
 
     @Override
     public void onClick(View v) {
+        Context context = getContext2();
+        MainActivity activity = getActivity2();
+        if (null == context || null == activity) {
+            return;
+        }
+
         if (mFab == v) {
             if (!mInAnimation) {
                 showEditPanel(true);
@@ -341,10 +357,10 @@ public final class GalleryCommentsScene extends ToolbarScene
                 EhRequest request = new EhRequest()
                         .setMethod(EhClient.METHOD_GET_COMMENT_GALLERY)
                         .setArgs(url, comment)
-                        .setCallback(new CommentGalleryListener(getContext(),
-                                ((StageActivity) getActivity()).getStageId(), getTag()));
-                EhApplication.getEhClient(getContext()).execute(request);
-                ActivityHelper.hideSoftInput(getActivity());
+                        .setCallback(new CommentGalleryListener(context,
+                                activity.getStageId(), getTag()));
+                EhApplication.getEhClient(context).execute(request);
+                hideSoftInput();
                 hideEditPanel(true);
             }
         }
@@ -378,19 +394,30 @@ public final class GalleryCommentsScene extends ToolbarScene
 
     private class CommentAdapter extends RecyclerView.Adapter<CommentHolder> {
 
+        private final LayoutInflater mInflater;
+
+        public CommentAdapter() {
+            mInflater = getLayoutInflater2();
+            AssertUtils.assertNotNull(mInflater);
+        }
+
         @Override
         public CommentHolder onCreateViewHolder(ViewGroup parent, int viewType) {
-            return new CommentHolder(getActivity().getLayoutInflater()
-                    .inflate(R.layout.item_gallery_comment, parent, false));
+            return new CommentHolder(mInflater.inflate(R.layout.item_gallery_comment, parent, false));
         }
 
         @Override
         public void onBindViewHolder(CommentHolder holder, int position) {
+            Context context = getContext2();
+            if (null == context) {
+                return;
+            }
+
             GalleryComment comment = mComments[position];
             holder.user.setText(comment.user);
             holder.time.setText(ReadableTime.getTimeAgo(comment.time));
             holder.comment.setText(TextUrl.handleTextUrl(Html.fromHtml(comment.comment,
-                    new URLImageGetter(holder.comment, EhApplication.getConaco(getContext())), null)));
+                    new URLImageGetter(holder.comment, EhApplication.getConaco(context)), null)));
         }
 
         @Override

app/src/main/java/com/hippo/ehviewer/ui/scene/GalleryDetailScene.java

@@ -16,8 +16,8 @@
 
 package com.hippo.ehviewer.ui.scene;
 
-import android.annotation.SuppressLint;
 import android.annotation.TargetApi;
+import android.app.Activity;
 import android.app.Dialog;
 import android.app.DownloadManager;
 import android.content.Context;
@@ -81,7 +81,6 @@ import com.hippo.ehviewer.ui.annotation.WholeLifeCircle;
 import com.hippo.rippleold.RippleSalon;
 import com.hippo.scene.Announcer;
 import com.hippo.scene.SceneFragment;
-import com.hippo.scene.StageActivity;
 import com.hippo.scene.TransitionHelper;
 import com.hippo.text.Html;
 import com.hippo.text.URLImageGetter;
@@ -96,6 +95,7 @@ import com.hippo.widget.LoadImageView;
 import com.hippo.widget.ProgressView;
 import com.hippo.widget.ProgressiveRatingBar;
 import com.hippo.widget.recyclerview.SimpleGridAutoSpanLayout;
+import com.hippo.yorozuya.AssertUtils;
 import com.hippo.yorozuya.SimpleHandler;
 import com.hippo.yorozuya.ViewUtils;
 
@@ -347,7 +347,9 @@ public class GalleryDetailScene extends BaseScene implements View.OnClickListene
 
         long gid = getGid();
         if (gid != -1) {
-            mDownloadState = EhApplication.getDownloadManager(getContext()).getDownloadState(gid);
+            Context context = getContext2();
+            AssertUtils.assertNotNull(context);
+            mDownloadState = EhApplication.getDownloadManager(context).getDownloadState(gid);
         } else {
             mDownloadState = DownloadInfo.STATE_INVALID;
         }
@@ -398,7 +400,10 @@ public class GalleryDetailScene extends BaseScene implements View.OnClickListene
         mTip = (TextView) ViewUtils.$$(main, R.id.tip);
         mViewTransition = new ViewTransition(mainView, progressView, mTip);
 
-        Drawable drawable = DrawableManager.getDrawable(getContext(), R.drawable.big_weird_face);
+        Context context = getContext2();
+        AssertUtils.assertNotNull(context);
+
+        Drawable drawable = DrawableManager.getDrawable(context, R.drawable.big_weird_face);
         drawable.setBounds(0, 0, drawable.getIntrinsicWidth(), drawable.getIntrinsicHeight());
         mTip.setCompoundDrawables(null, drawable, null, null);
         mTip.setOnClickListener(this);
@@ -491,7 +496,7 @@ public class GalleryDetailScene extends BaseScene implements View.OnClickListene
             adjustViewVisibility(STATE_FAILED, false);
         }
 
-        EhApplication.getDownloadManager(getContext()).addDownloadInfoListener(this);
+        EhApplication.getDownloadManager(context).addDownloadInfoListener(this);
 
         return view;
     }
@@ -505,7 +510,9 @@ public class GalleryDetailScene extends BaseScene implements View.OnClickListene
     public void onDestroyView() {
         super.onDestroyView();
 
-        EhApplication.getDownloadManager(getContext()).removeDownloadInfoListener(this);
+        Context context = getContext2();
+        AssertUtils.assertNotNull(context);
+        EhApplication.getDownloadManager(context).removeDownloadInfoListener(this);
 
         mTip = null;
         mViewTransition = null;
@@ -557,6 +564,9 @@ public class GalleryDetailScene extends BaseScene implements View.OnClickListene
     }
 
     private boolean prepareData() {
+        Context context = getContext2();
+        AssertUtils.assertNotNull(context);
+
         if (mGalleryDetail != null) {
             return true;
         }
@@ -567,12 +577,12 @@ public class GalleryDetailScene extends BaseScene implements View.OnClickListene
         }
 
         // Get from cache
-        mGalleryDetail = EhApplication.getGalleryDetailCache(getContext()).get(gid);
+        mGalleryDetail = EhApplication.getGalleryDetailCache(context).get(gid);
         if (mGalleryDetail != null) {
             return true;
         }
 
-        EhApplication application = (EhApplication) getContext().getApplicationContext();
+        EhApplication application = (EhApplication) context.getApplicationContext();
         if (application.containGlobalStuff(mRequestId)) {
             // request exist
             return true;
@@ -583,19 +593,21 @@ public class GalleryDetailScene extends BaseScene implements View.OnClickListene
     }
 
     private boolean request() {
+        Context context = getContext2();
+        MainActivity activity = getActivity2();
         String url = getGalleryDetailUrl(true);
-        if (url == null) {
+        if (null == context || null == activity || null == url) {
             return false;
         }
 
-        EhClient.Callback callback = new GetGalleryDetailListener(getContext(),
-                ((StageActivity) getActivity()).getStageId(), getTag());
-        mRequestId = ((EhApplication) getContext().getApplicationContext()).putGlobalStuff(callback);
+        EhClient.Callback callback = new GetGalleryDetailListener(context,
+                activity.getStageId(), getTag());
+        mRequestId = ((EhApplication) context.getApplicationContext()).putGlobalStuff(callback);
         EhRequest request = new EhRequest()
                 .setMethod(EhClient.METHOD_GET_GALLERY_DETAIL)
                 .setArgs(url)
                 .setCallback(callback);
-        EhApplication.getEhClient(getContext()).execute(request);
+        EhApplication.getEhClient(context).execute(request);
 
         return true;
     }
@@ -606,15 +618,17 @@ public class GalleryDetailScene extends BaseScene implements View.OnClickListene
     }
 
     private void ensureActionDrawable() {
-        Drawable heart = DrawableManager.getDrawable(getContext(), R.drawable.v_heart_primary_x48);
+        Context context = getContext2();
+        AssertUtils.assertNotNull(context);
+        Drawable heart = DrawableManager.getDrawable(context, R.drawable.v_heart_primary_x48);
         setActionDrawable(mHeart, heart);
-        Drawable heartOutline = DrawableManager.getDrawable(getContext(), R.drawable.v_heart_outline_primary_x48);
+        Drawable heartOutline = DrawableManager.getDrawable(context, R.drawable.v_heart_outline_primary_x48);
         setActionDrawable(mHeartOutline, heartOutline);
-        Drawable torrent = DrawableManager.getDrawable(getContext(), R.drawable.v_utorrent_primary_x48);
+        Drawable torrent = DrawableManager.getDrawable(context, R.drawable.v_utorrent_primary_x48);
         setActionDrawable(mTorrent, torrent);
-        Drawable share = DrawableManager.getDrawable(getContext(), R.drawable.v_share_primary_x48);
+        Drawable share = DrawableManager.getDrawable(context, R.drawable.v_share_primary_x48);
         setActionDrawable(mShare, share);
-        Drawable rate = DrawableManager.getDrawable(getContext(), R.drawable.v_thumb_up_primary_x48);
+        Drawable rate = DrawableManager.getDrawable(context, R.drawable.v_thumb_up_primary_x48);
         setActionDrawable(mRate, rate);
     }
 
@@ -733,7 +747,8 @@ public class GalleryDetailScene extends BaseScene implements View.OnClickListene
             return;
         }
 
-        Resources resources = getContext().getResources();
+        Resources resources = getResources2();
+        AssertUtils.assertNotNull(resources);
 
         mThumb.load(EhCacheKeyFactory.getThumbKey(gd.gid), gd.thumb, true);
         mTitle.setText(EhUtils.getSuitableTitle(gd));
@@ -763,7 +778,10 @@ public class GalleryDetailScene extends BaseScene implements View.OnClickListene
 
     @SuppressWarnings("deprecation")
     private void bindTags(GalleryTagGroup[] tagGroups) {
-        if (mTags == null || mNoTags == null) {
+        Context context = getContext2();
+        LayoutInflater inflater = getLayoutInflater2();
+        Resources resources = getResources2();
+        if (null == context || null == inflater || null == resources || null == mTags || null == mNoTags) {
             return;
         }
 
@@ -775,9 +793,8 @@ public class GalleryDetailScene extends BaseScene implements View.OnClickListene
             mNoTags.setVisibility(View.GONE);
         }
 
-        LayoutInflater inflater = getActivity().getLayoutInflater();
-        int colorTag = getResources().getColor(R.color.colorPrimary);
-        int colorName = getResources().getColor(R.color.purple_a400);
+        int colorTag = resources.getColor(R.color.colorPrimary);
+        int colorName = resources.getColor(R.color.purple_a400);
         for (GalleryTagGroup tg : tagGroups) {
             LinearLayout ll = (LinearLayout) inflater.inflate(R.layout.gallery_tag_group, mTags, false);
             ll.setOrientation(LinearLayout.HORIZONTAL);
@@ -788,7 +805,7 @@ public class GalleryDetailScene extends BaseScene implements View.OnClickListene
             tgName.setText(tg.groupName);
             tgName.setBackgroundDrawable(new RoundSideRectDrawable(colorName));
 
-            AutoWrapLayout awl = new AutoWrapLayout(getContext());
+            AutoWrapLayout awl = new AutoWrapLayout(context);
             ll.addView(awl, ViewGroup.LayoutParams.WRAP_CONTENT, ViewGroup.LayoutParams.WRAP_CONTENT);
             for (int j = 0, z = tg.size(); j < z; j++) {
                 TextView tag = (TextView) inflater.inflate(R.layout.item_gallery_tag, awl, false);
@@ -804,7 +821,9 @@ public class GalleryDetailScene extends BaseScene implements View.OnClickListene
     }
 
     private void bindComments(GalleryComment[] comments) {
-        if (mComments == null || mCommentsText == null) {
+        Context context = getContext2();
+        LayoutInflater inflater = getLayoutInflater2();
+        if (null == context || null == inflater || null == mComments || null == mCommentsText) {
             return;
         }
 
@@ -820,7 +839,6 @@ public class GalleryDetailScene extends BaseScene implements View.OnClickListene
             mCommentsText.setText(R.string.more_comment);
         }
 
-        LayoutInflater inflater = getActivity().getLayoutInflater();
         int length = Math.min(maxShowCount, comments.length);
         for (int i = 0; i < length; i++) {
             GalleryComment comment = comments[i];
@@ -833,12 +851,14 @@ public class GalleryDetailScene extends BaseScene implements View.OnClickListene
             TextView c = (TextView) v.findViewById(R.id.comment);
             c.setMaxLines(5);
             c.setText(Html.fromHtml(comment.comment,
-                    new URLImageGetter(c, EhApplication.getConaco(getContext())), null));
+                    new URLImageGetter(c, EhApplication.getConaco(context)), null));
         }
     }
 
     private void bindPreviews(GalleryDetail gd) {
-        if (mGridLayout == null || mPreviewText == null) {
+        LayoutInflater inflater = getLayoutInflater2();
+        Resources resources = getResources2();
+        if (null == inflater || null == resources || null == mGridLayout || null == mPreviewText) {
             return;
         }
 
@@ -853,10 +873,9 @@ public class GalleryDetailScene extends BaseScene implements View.OnClickListene
             mPreviewText.setText(R.string.more_previews);
         }
 
-        int columnWidth = getResources().getDimensionPixelOffset(R.dimen.preview_grid_column_width);
+        int columnWidth = resources.getDimensionPixelOffset(R.dimen.preview_grid_column_width);
         mGridLayout.setColumnSize(columnWidth);
         mGridLayout.setStrategy(SimpleGridAutoSpanLayout.STRATEGY_SUITABLE_SIZE);
-        LayoutInflater inflater = getActivity().getLayoutInflater();
         for (int i = 0, size = previewSet.size(); i < size; i++) {
             View view = inflater.inflate(R.layout.item_gallery_preview, mGridLayout, false);
             mGridLayout.addView(view);
@@ -912,7 +931,8 @@ public class GalleryDetailScene extends BaseScene implements View.OnClickListene
     }
 
     private String getAllRatingText(float rating, int ratedTimes) {
-        Resources resources = getResources();
+        Resources resources = getResources2();
+        AssertUtils.assertNotNull(resources);
         return resources.getString(R.string.rating_text, getRatingText(rating, resources), rating, ratedTimes);
     }
 
@@ -934,7 +954,9 @@ public class GalleryDetailScene extends BaseScene implements View.OnClickListene
             return;
         }
 
-        PopupMenu popup = new PopupMenu(getContext(), mOtherActions, Gravity.TOP);
+        Context context = getContext2();
+        AssertUtils.assertNotNull(context);
+        PopupMenu popup = new PopupMenu(context, mOtherActions, Gravity.TOP);
         mPopupMenu = popup;
         popup.getMenuInflater().inflate(R.menu.scene_gallery_detail, popup.getMenu());
         popup.setOnMenuItemClickListener(new PopupMenu.OnMenuItemClickListener() {
@@ -943,8 +965,9 @@ public class GalleryDetailScene extends BaseScene implements View.OnClickListene
                 switch (item.getItemId()) {
                     case R.id.action_open_in_other_app:
                         String url = getGalleryDetailUrl(false);
-                        if (url != null) {
-                            UrlOpener.openUrl(getActivity(), url, false, false);
+                        Activity activity = getActivity2();
+                        if (null != url && null != activity) {
+                            UrlOpener.openUrl(activity, url, false, false);
                         }
                         break;
                     case R.id.action_refresh:
@@ -961,6 +984,12 @@ public class GalleryDetailScene extends BaseScene implements View.OnClickListene
 
     @Override
     public void onClick(View v) {
+        Context context = getContext2();
+        MainActivity activity = getActivity2();
+        if (null == context || null == activity) {
+            return;
+        }
+
         if (mTip == v) {
             if (request()) {
                 adjustViewVisibility(STATE_REFRESH, true);
@@ -990,7 +1019,7 @@ public class GalleryDetailScene extends BaseScene implements View.OnClickListene
         } else if (mDownload == v) {
             GalleryInfo galleryInfo = getGalleryInfo();
             if (galleryInfo != null) {
-                CommonOperations.startDownload((MainActivity) getActivity(), galleryInfo, false);
+                CommonOperations.startDownload(activity, galleryInfo, false);
             }
         } else if (mRead == v) {
             GalleryInfo galleryInfo = null;
@@ -1000,7 +1029,7 @@ public class GalleryDetailScene extends BaseScene implements View.OnClickListene
                 galleryInfo = mGalleryDetail;
             }
             if (galleryInfo != null) {
-                Intent intent = new Intent(getActivity(), GalleryActivity.class);
+                Intent intent = new Intent(activity, GalleryActivity.class);
                 intent.setAction(GalleryActivity.ACTION_EH);
                 intent.putExtra(GalleryActivity.KEY_GALLERY_INFO, galleryInfo);
                 startActivity(intent);
@@ -1018,16 +1047,16 @@ public class GalleryDetailScene extends BaseScene implements View.OnClickListene
                 }
                 if (mGalleryDetail.isFavored) {
                     mModifingFavorites = true;
-                    CommonOperations.removeFromFavorites(getActivity(), mGalleryDetail,
-                            new ModifyFavoritesListener(getContext(),
-                                    ((StageActivity) getActivity()).getStageId(), getTag(), true));
+                    CommonOperations.removeFromFavorites(activity, mGalleryDetail,
+                            new ModifyFavoritesListener(context,
+                                    activity.getStageId(), getTag(), true));
                     remove = true;
                 }
                 if (!remove) {
                     mModifingFavorites = true;
-                    CommonOperations.addToFavorites(getActivity(), mGalleryDetail,
-                            new ModifyFavoritesListener(getContext(),
-                                    ((StageActivity) getActivity()).getStageId(), getTag(), false));
+                    CommonOperations.addToFavorites(activity, mGalleryDetail,
+                            new ModifyFavoritesListener(context,
+                                    activity.getStageId(), getTag(), false));
                 }
                 // Update UI
                 updateFavoriteDrawable();
@@ -1035,29 +1064,30 @@ public class GalleryDetailScene extends BaseScene implements View.OnClickListene
         } else if (mShare == v) {
             String url = getGalleryDetailUrl(false);
             if (url != null) {
-                ActivityHelper.share(getActivity(), url);
+                ActivityHelper.share(activity, url);
             }
         } else if (mTorrent == v) {
             if (mGalleryDetail != null) {
-                TorrentListDialogHelper helper = new TorrentListDialogHelper(mGalleryDetail.torrentUrl);
-                Dialog dialog = new AlertDialog.Builder(getContext())
+                TorrentListDialogHelper helper = new TorrentListDialogHelper();
+                Dialog dialog = new AlertDialog.Builder(context)
                         .setTitle(R.string.torrents)
-                        .setView(helper.getView())
+                        .setView(R.layout.dialog_torrent_list)
                         .setOnDismissListener(helper)
                         .show();
-                helper.setDialog(dialog);
+                helper.setDialog(dialog, mGalleryDetail.torrentUrl);
             }
         } else if (mRate == v) {
             if (mGalleryDetail == null) {
                 return;
             }
-            RateDialogHelper helper = new RateDialogHelper(mGalleryDetail.rating);
-            new AlertDialog.Builder(getContext())
+            RateDialogHelper helper = new RateDialogHelper();
+            Dialog dialog = new AlertDialog.Builder(context)
                     .setTitle(R.string.rate)
-                    .setView(helper.view)
+                    .setView(R.layout.dialog_rate)
                     .setNegativeButton(android.R.string.cancel, null)
                     .setPositiveButton(android.R.string.ok, helper)
                     .show();
+            helper.setDialog(dialog, mGalleryDetail.rating);
         } else if (mComments == v) {
             if (mGalleryDetail == null) {
                 return;
@@ -1086,10 +1116,9 @@ public class GalleryDetailScene extends BaseScene implements View.OnClickListene
                 return;
             }
 
-            Context context = getContext();
             GalleryInfo galleryInfo = getGalleryInfo();
             o = v.getTag(R.id.index);
-            if (null != context && null != galleryInfo && o instanceof Integer) {
+            if (null != galleryInfo && o instanceof Integer) {
                 int index = (Integer) o;
                 Intent intent = new Intent(context, GalleryActivity.class);
                 intent.setAction(GalleryActivity.ACTION_EH);
@@ -1102,12 +1131,16 @@ public class GalleryDetailScene extends BaseScene implements View.OnClickListene
     }
 
     private void showBlockUploaderDialog() {
+        Context context = getContext2();
+        if (null == context) {
+            return;
+        }
         final String uploader = getUploader();
         if (null == uploader) {
             return;
         }
 
-        new AlertDialog.Builder(getContext())
+        new AlertDialog.Builder(context)
                 .setMessage(getString(R.string.block_the_uploader, uploader))
                 .setPositiveButton(android.R.string.ok, new DialogInterface.OnClickListener() {
                     @Override
@@ -1127,7 +1160,12 @@ public class GalleryDetailScene extends BaseScene implements View.OnClickListene
     }
 
     private void showBlockTagDialog(final String tag) {
-        new AlertDialog.Builder(getContext())
+        Context context = getContext2();
+        if (null == context) {
+            return;
+        }
+
+        new AlertDialog.Builder(context)
                 .setMessage(getString(R.string.block_the_tag, tag))
                 .setPositiveButton(android.R.string.ok, new DialogInterface.OnClickListener() {
                     @Override
@@ -1148,12 +1186,17 @@ public class GalleryDetailScene extends BaseScene implements View.OnClickListene
 
     @Override
     public boolean onLongClick(View v) {
+        MainActivity activity = getActivity2();
+        if (null == activity) {
+            return false;
+        }
+
         if (mUploader == v) {
             showBlockUploaderDialog();
         } else if (mDownload == v) {
             GalleryInfo galleryInfo = getGalleryInfo();
             if (galleryInfo != null) {
-                CommonOperations.startDownload((MainActivity) getActivity(), galleryInfo, true);
+                CommonOperations.startDownload(activity, galleryInfo, true);
             }
             return true;
         } else {
@@ -1230,12 +1273,13 @@ public class GalleryDetailScene extends BaseScene implements View.OnClickListene
     }
 
     private void updateDownloadState() {
+        Context context = getContext2();
         long gid = getGid();
-        if (-1L == gid) {
+        if (null == context || -1L == gid) {
             return;
         }
 
-        int downloadState = EhApplication.getDownloadManager(getContext()).getDownloadState(gid);
+        int downloadState = EhApplication.getDownloadManager(context).getDownloadState(gid);
         if (downloadState == mDownloadState) {
             return;
         }
@@ -1320,12 +1364,11 @@ public class GalleryDetailScene extends BaseScene implements View.OnClickListene
 
     private void onGetGalleryDetailFailure(Exception e) {
         e.printStackTrace();
-        if (isViewCreated()) {
-            String error = ExceptionUtils.getReadableString(getContext(), e);
-            if (mTip != null) {
-                mTip.setText(error);
-                adjustViewVisibility(STATE_FAILED, true);
-            }
+        Context context = getContext2();
+        if (null != context && null != mTip) {
+            String error = ExceptionUtils.getReadableString(context, e);
+            mTip.setText(error);
+            adjustViewVisibility(STATE_FAILED, true);
         }
     }
 
@@ -1390,42 +1433,41 @@ public class GalleryDetailScene extends BaseScene implements View.OnClickListene
     private class TorrentListDialogHelper implements AdapterView.OnItemClickListener,
             DialogInterface.OnDismissListener, EhClient.Callback<Pair<String, String>[]> {
 
-        private final View mView;
-        private final ProgressView mProgressView;
-        private final TextView mErrorText;
-        private final ListView mListView;
-
+        @Nullable
+        private ProgressView mProgressView;
+        @Nullable
+        private TextView mErrorText;
+        @Nullable
+        private ListView mListView;
         @Nullable
         private EhRequest mRequest;
         @Nullable
         private Dialog mDialog;
 
-        @SuppressLint("InflateParams")
-        public TorrentListDialogHelper(String url) {
-            mView = getActivity().getLayoutInflater().inflate(R.layout.dialog_torrent_list, null);
-            mProgressView = (ProgressView) ViewUtils.$$(mView, R.id.progress);
-            mErrorText = (TextView) ViewUtils.$$(mView, R.id.text);
-            mListView = (ListView) ViewUtils.$$(mView, R.id.list_view);
+        public void setDialog(@Nullable Dialog dialog, String url) {
+            mDialog = dialog;
+            mProgressView = (ProgressView) ViewUtils.$$(dialog, R.id.progress);
+            mErrorText = (TextView) ViewUtils.$$(dialog, R.id.text);
+            mListView = (ListView) ViewUtils.$$(dialog, R.id.list_view);
             mListView.setOnItemClickListener(this);
 
-            if (mTorrentList == null) {
-                mErrorText.setVisibility(View.GONE);
-                mListView.setVisibility(View.GONE);
-                mRequest = new EhRequest().setMethod(EhClient.METHOD_GET_TORRENT_LIST)
-                        .setArgs(url)
-                        .setCallback(this);
-                EhApplication.getEhClient(getContext()).execute(mRequest);
-            } else {
-                bind(mTorrentList);
+            Context context = getContext2();
+            if (context != null) {
+                if (mTorrentList == null) {
+                    mErrorText.setVisibility(View.GONE);
+                    mListView.setVisibility(View.GONE);
+                    mRequest = new EhRequest().setMethod(EhClient.METHOD_GET_TORRENT_LIST)
+                            .setArgs(url)
+                            .setCallback(this);
+                    EhApplication.getEhClient(context).execute(mRequest);
+                } else {
+                    bind(mTorrentList);
+                }
             }
         }
 
-        public void setDialog(@Nullable Dialog dialog) {
-            mDialog = dialog;
-        }
-
         private void bind(Pair<String, String>[] data) {
-            if (null == mDialog) {
+            if (null == mDialog || null == mProgressView || null == mErrorText || null == mListView) {
                 return;
             }
 
@@ -1446,13 +1488,10 @@ public class GalleryDetailScene extends BaseScene implements View.OnClickListene
             }
         }
 
-        public View getView() {
-            return mView;
-        }
-
         @Override
         public void onItemClick(AdapterView<?> parent, View view, int position, long id) {
-            if (mTorrentList != null && position < mTorrentList.length) {
+            Context context = getContext2();
+            if (null != context && null != mTorrentList && position < mTorrentList.length) {
                 String url = mTorrentList[position].first;
                 String name = mTorrentList[position].second;
                 // Use system download service
@@ -1460,7 +1499,7 @@ public class GalleryDetailScene extends BaseScene implements View.OnClickListene
                 r.setDestinationInExternalPublicDir(Environment.DIRECTORY_DOWNLOADS, name + ".torrent");
                 r.allowScanningByMediaScanner();
                 r.setNotificationVisibility(DownloadManager.Request.VISIBILITY_VISIBLE_NOTIFY_COMPLETED);
-                DownloadManager dm = (DownloadManager) getContext().getSystemService(Context.DOWNLOAD_SERVICE);
+                DownloadManager dm = (DownloadManager) context.getSystemService(Context.DOWNLOAD_SERVICE);
                 dm.enqueue(r);
             }
 
@@ -1477,6 +1516,9 @@ public class GalleryDetailScene extends BaseScene implements View.OnClickListene
                 mRequest = null;
             }
             mDialog = null;
+            mProgressView = null;
+            mErrorText = null;
+            mListView = null;
         }
 
         @Override
@@ -1490,12 +1532,13 @@ public class GalleryDetailScene extends BaseScene implements View.OnClickListene
 
         @Override
         public void onFailure(Exception e) {
-            if (mRequest != null) {
-                mRequest = null;
+            mRequest = null;
+            Context context = getContext2();
+            if (null != context && null != mProgressView && null != mErrorText && null != mListView) {
                 mProgressView.setVisibility(View.GONE);
                 mErrorText.setVisibility(View.VISIBLE);
                 mListView.setVisibility(View.GONE);
-                mErrorText.setText(ExceptionUtils.getReadableString(getContext(), e));
+                mErrorText.setText(ExceptionUtils.getReadableString(context, e));
             }
         }
 
@@ -1554,37 +1597,41 @@ public class GalleryDetailScene extends BaseScene implements View.OnClickListene
     private class RateDialogHelper implements ProgressiveRatingBar.OnUserRateListener,
             DialogInterface.OnClickListener {
 
-        public View view;
-        private final ProgressiveRatingBar mRatingBar;
-        private final TextView mRatingText;
+        @Nullable
+        private ProgressiveRatingBar mRatingBar;
+        @Nullable
+        private TextView mRatingText;
 
-        @SuppressLint("InflateParams")
-        private RateDialogHelper(float rating) {
-            view = getActivity().getLayoutInflater().inflate(R.layout.dialog_rate, null);
-            mRatingText = (TextView) view.findViewById(R.id.rating_text);
-            mRatingBar = (ProgressiveRatingBar) view.findViewById(R.id.rating_view);
-            mRatingText.setText(getRatingText(rating, getResources()));
+        public void setDialog(Dialog dialog, float rating) {
+            mRatingText = (TextView) ViewUtils.$$(dialog, R.id.rating_text);
+            mRatingBar = (ProgressiveRatingBar) ViewUtils.$$(dialog, R.id.rating_view);
+            mRatingText.setText(getRatingText(rating, getResources2()));
             mRatingBar.setRating(rating);
             mRatingBar.setOnUserRateListener(this);
         }
 
         @Override
         public void onUserRate(float rating) {
-            mRatingText.setText(getRatingText(rating, getResources()));
+            if (null != mRatingText) {
+                mRatingText.setText(getRatingText(rating, getResources2()));
+            }
         }
 
         @Override
         public void onClick(DialogInterface dialog, int which) {
-            if (which != DialogInterface.BUTTON_POSITIVE || mGalleryDetail == null) {
+            Context context = getContext2();
+            MainActivity activity = getActivity2();
+            if (null == context || null == activity || which != DialogInterface.BUTTON_POSITIVE ||
+                    null == mGalleryDetail || null == mRatingBar) {
                 return;
             }
 
             EhRequest request = new EhRequest()
                     .setMethod(EhClient.METHOD_GET_RATE_GALLERY)
                     .setArgs(mGalleryDetail.gid, mGalleryDetail.token, mRatingBar.getRating())
-                    .setCallback(new RateGalleryListener(getContext(),
-                            ((StageActivity) getActivity()).getStageId(), getTag(), mGalleryDetail.gid));
-            EhApplication.getEhClient(getContext()).execute(request);
+                    .setCallback(new RateGalleryListener(context,
+                            activity.getStageId(), getTag(), mGalleryDetail.gid));
+            EhApplication.getEhClient(context).execute(request);
         }
     }
 

app/src/main/java/com/hippo/ehviewer/ui/scene/GalleryInfoScene.java

@@ -37,6 +37,7 @@ import com.hippo.ehviewer.client.EhUrl;
 import com.hippo.ehviewer.client.EhUtils;
 import com.hippo.ehviewer.client.data.GalleryDetail;
 import com.hippo.rippleold.RippleSalon;
+import com.hippo.yorozuya.AssertUtils;
 import com.hippo.yorozuya.LayoutUtils;
 import com.hippo.yorozuya.ViewUtils;
 
@@ -79,7 +80,8 @@ public final class GalleryInfoScene extends ToolbarScene implements EasyRecycler
             return;
         }
 
-        Resources resources = getResources();
+        Resources resources = getResources2();
+        AssertUtils.assertNotNull(resources);
         mKeys.add(resources.getString(R.string.header_key));
         mValues.add(resources.getString(R.string.header_value));
         mKeys.add(resources.getString(R.string.key_gid));
@@ -151,14 +153,17 @@ public final class GalleryInfoScene extends ToolbarScene implements EasyRecycler
             @Nullable ViewGroup container, @Nullable Bundle savedInstanceState) {
         View view = inflater.inflate(R.layout.scene_gallery_info, container, false);
 
+        Context context = getContext2();
+        AssertUtils.assertNotNull(context);
+
         EasyRecyclerView recyclerView = (EasyRecyclerView) ViewUtils.$$(view, R.id.recycler_view);
         InfoAdapter adapter = new InfoAdapter();
         recyclerView.setAdapter(adapter);
-        recyclerView.setLayoutManager(new LinearLayoutManager(getContext(), LinearLayoutManager.VERTICAL, false));
+        recyclerView.setLayoutManager(new LinearLayoutManager(context, LinearLayoutManager.VERTICAL, false));
         LinearDividerItemDecoration decoration = new LinearDividerItemDecoration(
-                LinearDividerItemDecoration.VERTICAL, getResources().getColor(R.color.divider),
-                LayoutUtils.dp2pix(getContext(), 1));
-        decoration.setPadding(getResources().getDimensionPixelOffset(R.dimen.keyline_margin));
+                LinearDividerItemDecoration.VERTICAL, context.getResources().getColor(R.color.divider),
+                LayoutUtils.dp2pix(context, 1));
+        decoration.setPadding(context.getResources().getDimensionPixelOffset(R.dimen.keyline_margin));
         recyclerView.addItemDecoration(decoration);
         recyclerView.setSelector(RippleSalon.generateRippleDrawable(false));
         recyclerView.setClipToPadding(false);
@@ -176,8 +181,9 @@ public final class GalleryInfoScene extends ToolbarScene implements EasyRecycler
 
     @Override
     public boolean onItemClick(EasyRecyclerView parent, View view, int position, long id) {
-        if (position != 0 && mValues != null) {
-            ClipboardManager cmb = (ClipboardManager) getContext().getSystemService(Context.CLIPBOARD_SERVICE);
+        Context context = getContext2();
+        if (null != context && 0 != position && null != mValues) {
+            ClipboardManager cmb = (ClipboardManager) context.getSystemService(Context.CLIPBOARD_SERVICE);
             cmb.setPrimaryClip(ClipData.newPlainText(null, mValues.get(position)));
             showTip(R.string.copied_to_clipboard, LENGTH_SHORT);
             return true;
@@ -209,6 +215,13 @@ public final class GalleryInfoScene extends ToolbarScene implements EasyRecycler
         private static final int TYPE_HEADER = 0;
         private static final int TYPE_DATA = 1;
 
+        private final LayoutInflater mInflater;
+
+        public InfoAdapter() {
+            mInflater = getLayoutInflater2();
+            AssertUtils.assertNotNull(mInflater);
+        }
+
         @Override
         public int getItemViewType(int position) {
             if (position == 0) {
@@ -220,7 +233,7 @@ public final class GalleryInfoScene extends ToolbarScene implements EasyRecycler
 
         @Override
         public InfoHolder onCreateViewHolder(ViewGroup parent, int viewType) {
-            return new InfoHolder(getActivity().getLayoutInflater().inflate(viewType == TYPE_HEADER ?
+            return new InfoHolder(mInflater.inflate(viewType == TYPE_HEADER ?
                     R.layout.item_gallery_info_header : R.layout.item_gallery_info_data, parent, false));
         }
 

app/src/main/java/com/hippo/ehviewer/ui/scene/GalleryListScene.java

@@ -17,6 +17,7 @@
 package com.hippo.ehviewer.ui.scene;
 
 import android.animation.Animator;
+import android.app.Activity;
 import android.content.Context;
 import android.content.DialogInterface;
 import android.content.res.Resources;
@@ -72,7 +73,6 @@ import com.hippo.ehviewer.widget.SearchLayout;
 import com.hippo.rippleold.RippleSalon;
 import com.hippo.scene.Announcer;
 import com.hippo.scene.SceneFragment;
-import com.hippo.scene.StageActivity;
 import com.hippo.util.ApiHelper;
 import com.hippo.util.DrawableManager;
 import com.hippo.view.ViewTransition;
@@ -81,6 +81,7 @@ import com.hippo.widget.SearchBarMover;
 import com.hippo.widget.recyclerview.GridAutoSpanLayoutManager;
 import com.hippo.widget.refreshlayout.RefreshLayout;
 import com.hippo.yorozuya.AnimationUtils;
+import com.hippo.yorozuya.AssertUtils;
 import com.hippo.yorozuya.MathUtils;
 import com.hippo.yorozuya.SimpleAnimatorListener;
 import com.hippo.yorozuya.SimpleHandler;
@@ -210,7 +211,9 @@ public final class GalleryListScene extends BaseScene
     public void onCreate(@Nullable Bundle savedInstanceState) {
         super.onCreate(savedInstanceState);
 
-        mClient = EhApplication.getEhClient(getContext());
+        Context context = getContext2();
+        AssertUtils.assertNotNull(context);
+        mClient = EhApplication.getEhClient(context);
 
         if (savedInstanceState == null) {
             onInit();
@@ -291,11 +294,11 @@ public final class GalleryListScene extends BaseScene
     // Update search bar title, drawer checked item
     private void onUpdateUrlBuilder() {
         ListUrlBuilder builder = mUrlBuilder;
-        if (null == builder) {
+        Resources resources = getResources2();
+        if (null == resources || null == builder) {
             return;
         }
 
-        Resources resources = getResources();
         String keyword = builder.getKeyword();
         int category = builder.getCategory();
 
@@ -305,7 +308,7 @@ public final class GalleryListScene extends BaseScene
         }
 
         // Update title
-        String title = getSuitableTitleForUrlBuilder(getResources(), builder, true);
+        String title = getSuitableTitleForUrlBuilder(resources, builder, true);
         if (null == title) {
             title = resources.getString(R.string.search);
         }
@@ -334,7 +337,9 @@ public final class GalleryListScene extends BaseScene
             @Nullable Bundle savedInstanceState) {
         View view = inflater.inflate(R.layout.scene_gallery_list, container, false);
 
-        Resources resources = getContext().getResources();
+        Context context = getContext2();
+        AssertUtils.assertNotNull(context);
+        Resources resources = context.getResources();
 
         View mainLayout = ViewUtils.$$(view, R.id.main_layout);
         ContentLayout contentLayout = (ContentLayout) ViewUtils.$$(mainLayout, R.id.content_layout);
@@ -355,7 +360,7 @@ public final class GalleryListScene extends BaseScene
         contentLayout.setHelper(mHelper);
         contentLayout.getFastScroller().setOnDragHandlerListener(this);
 
-        GridAutoSpanLayoutManager layoutManager = new GridAutoSpanLayoutManager(getContext(), 0);
+        GridAutoSpanLayoutManager layoutManager = new GridAutoSpanLayoutManager(context, 0);
         mRecyclerView.setLayoutManager(layoutManager);
         mRecyclerView.setSelector(RippleSalon.generateRippleDrawable(false));
         mRecyclerView.setDrawSelectorOnTop(true);
@@ -363,8 +368,8 @@ public final class GalleryListScene extends BaseScene
         mRecyclerView.setClipToPadding(false);
         mRecyclerView.setOnItemClickListener(this);
         mRecyclerView.setOnItemLongClickListener(this);
-        mAdapter = new GalleryListAdapter(LayoutInflater.from(getContext()),
-                getContext(), mRecyclerView, layoutManager, Settings.getListMode());
+        mAdapter = new GalleryListAdapter(getLayoutInflater2(), getResources2(),
+                mRecyclerView, layoutManager, Settings.getListMode());
         mRecyclerView.setAdapter(mAdapter);
         mAdapter.register();
         mRecyclerView.setPadding(mRecyclerView.getPaddingLeft(), mRecyclerView.getPaddingTop() + paddingTopSB,
@@ -375,13 +380,13 @@ public final class GalleryListScene extends BaseScene
 
         refreshLayout.setHeaderTranslationY(paddingTopSB);
 
-        mLeftDrawable = new DrawerArrowDrawable(getContext());
-        mRightDrawable = new AddDeleteDrawable(getContext());
+        mLeftDrawable = new DrawerArrowDrawable(context);
+        mRightDrawable = new AddDeleteDrawable(context);
         mSearchBar.setLeftDrawable(mLeftDrawable);
         mSearchBar.setRightDrawable(mRightDrawable);
         mSearchBar.setHelper(this);
         mSearchBar.setOnStateChangeListener(this);
-        setSearchBarHint(getContext(), mSearchBar);
+        setSearchBarHint(context, mSearchBar);
 
         mSearchLayout.setHelper(this);
         mSearchLayout.setPadding(mSearchLayout.getPaddingLeft(), mSearchLayout.getPaddingTop() + paddingTopSB,
@@ -411,15 +416,16 @@ public final class GalleryListScene extends BaseScene
     }
 
     private void guideQuickSearch() {
-        if (!Settings.getGuideQuickSearch()) {
+        Activity activity = getActivity2();
+        if (null == activity || !Settings.getGuideQuickSearch()) {
             return;
         }
 
-        Display display = getActivity().getWindowManager().getDefaultDisplay();
+        Display display = activity.getWindowManager().getDefaultDisplay();
         Point point = new Point();
         display.getSize(point);
 
-        new ShowcaseView.Builder(getActivity())
+        new ShowcaseView.Builder(activity)
                 .withMaterialShowcase()
                 .setStyle(R.style.Guide)
                 .setTarget(new PointTarget(point.x, point.y / 3))
@@ -468,12 +474,13 @@ public final class GalleryListScene extends BaseScene
 
     private void showAddQuickSearchDialog(final List<QuickSearch> list,
             final ArrayAdapter<QuickSearch> adapter, final ListView listView, final TextView tip) {
-        if (null == mUrlBuilder) {
+        Context context = getContext2();
+        if (null == context || null == mUrlBuilder) {
             return;
         }
 
-        final EditTextDialogBuilder builder = new EditTextDialogBuilder(getContext(),
-                getSuitableTitleForUrlBuilder(getResources(), mUrlBuilder, false), getString(R.string.quick_search));
+        final EditTextDialogBuilder builder = new EditTextDialogBuilder(context,
+                getSuitableTitleForUrlBuilder(context.getResources(), mUrlBuilder, false), getString(R.string.quick_search));
         builder.setTitle(R.string.add_quick_search_dialog_title);
         builder.setPositiveButton(android.R.string.ok, null);
         final AlertDialog dialog = builder.show();
@@ -512,8 +519,11 @@ public final class GalleryListScene extends BaseScene
         final TextView tip = (TextView) ViewUtils.$$(view, R.id.tip);
         final ListView listView = (ListView) ViewUtils.$$(view, R.id.list_view);
 
+        Context context = getContext2();
+        AssertUtils.assertNotNull(context);
+
         final List<QuickSearch> list = EhDB.getAllQuickSearch();
-        final ArrayAdapter<QuickSearch> adapter = new ArrayAdapter<>(getContext(), R.layout.item_simple_list, list);
+        final ArrayAdapter<QuickSearch> adapter = new ArrayAdapter<>(context, R.layout.item_simple_list, list);
         listView.setAdapter(adapter);
         listView.setOnItemClickListener(new AdapterView.OnItemClickListener() {
             @Override
@@ -634,24 +644,26 @@ public final class GalleryListScene extends BaseScene
 
     @Override
     public boolean onItemLongClick(EasyRecyclerView parent, View view, int position, long id) {
-        if (null == mHelper) {
+        final Context context = getContext2();
+        final MainActivity activity = getActivity2();
+        if (null == context || null == activity || null == mHelper) {
             return false;
         }
 
         final GalleryInfo gi = mHelper.getDataAt(position);
-        new AlertDialog.Builder(getContext())
+        new AlertDialog.Builder(context)
                 .setTitle(EhUtils.getSuitableTitle(gi))
                 .setItems(R.array.gallery_list_menu_entries, new DialogInterface.OnClickListener() {
                     @Override
                     public void onClick(DialogInterface dialog, int which) {
                         switch (which) {
                             case 0: // Download
-                                CommonOperations.startDownload((MainActivity) getActivity(), gi, false);
+                                CommonOperations.startDownload(activity, gi, false);
                                 break;
                             case 1: // Favorites
-                                CommonOperations.addToFavorites(getActivity(), gi,
-                                        new addToFavoriteListener(getContext(),
-                                                ((StageActivity) getActivity()).getStageId(), getTag()));
+                                CommonOperations.addToFavorites(activity, gi,
+                                        new addToFavoriteListener(context,
+                                                activity.getStageId(), getTag()));
                                 break;
                         }
                     }
@@ -945,9 +957,9 @@ public final class GalleryListScene extends BaseScene
 
     private class GalleryListAdapter extends GalleryAdapter {
 
-        public GalleryListAdapter(LayoutInflater inflater, Context context,
+        public GalleryListAdapter(LayoutInflater inflater, Resources resources,
                 RecyclerView recyclerView, GridAutoSpanLayoutManager layoutManager, int type) {
-            super(inflater, context, recyclerView, layoutManager, type);
+            super(inflater, resources, recyclerView, layoutManager, type);
         }
 
         @Override
@@ -966,7 +978,8 @@ public final class GalleryListScene extends BaseScene
 
         @Override
         protected void getPageData(int taskId, int type, int page) {
-            if (null == mClient || null == mUrlBuilder) {
+            MainActivity activity = getActivity2();
+            if (null == activity || null == mClient || null == mUrlBuilder) {
                 return;
             }
 
@@ -975,7 +988,7 @@ public final class GalleryListScene extends BaseScene
                 EhRequest request = new EhRequest();
                 request.setMethod(EhClient.METHOD_GET_WHATS_HOT);
                 request.setCallback(new GetWhatsHotListener(getContext(),
-                        ((StageActivity) getActivity()).getStageId(), getTag(), taskId));
+                        activity.getStageId(), getTag(), taskId));
                 request.setArgs();
                 mClient.execute(request);
             } else {
@@ -983,7 +996,7 @@ public final class GalleryListScene extends BaseScene
                 EhRequest request = new EhRequest();
                 request.setMethod(EhClient.METHOD_GET_GALLERY_LIST);
                 request.setCallback(new GetGalleryListListener(getContext(),
-                        ((StageActivity) getActivity()).getStageId(), getTag(), taskId));
+                        activity.getStageId(), getTag(), taskId));
                 request.setArgs(url);
                 mClient.execute(request);
             }
@@ -991,7 +1004,7 @@ public final class GalleryListScene extends BaseScene
 
         @Override
         protected Context getContext() {
-            return GalleryListScene.this.getContext();
+            return GalleryListScene.this.getContext2();
         }
 
         @Override

app/src/main/java/com/hippo/ehviewer/ui/scene/GalleryPreviewsScene.java

@@ -16,11 +16,11 @@
 
 package com.hippo.ehviewer.ui.scene;
 
-import android.annotation.SuppressLint;
 import android.app.Dialog;
 import android.content.Context;
 import android.content.DialogInterface;
 import android.content.Intent;
+import android.content.res.Resources;
 import android.os.Bundle;
 import android.support.annotation.NonNull;
 import android.support.annotation.Nullable;
@@ -46,14 +46,16 @@ import com.hippo.ehviewer.client.data.GalleryPreview;
 import com.hippo.ehviewer.client.data.LargePreviewSet;
 import com.hippo.ehviewer.client.exception.EhException;
 import com.hippo.ehviewer.ui.GalleryActivity;
+import com.hippo.ehviewer.ui.MainActivity;
 import com.hippo.scene.SceneFragment;
-import com.hippo.scene.StageActivity;
 import com.hippo.widget.ContentLayout;
 import com.hippo.widget.LoadImageView;
 import com.hippo.widget.Slider;
 import com.hippo.widget.recyclerview.GridAutoSpanLayoutManager;
+import com.hippo.yorozuya.AssertUtils;
 import com.hippo.yorozuya.LayoutUtils;
 import com.hippo.yorozuya.SimpleHandler;
+import com.hippo.yorozuya.ViewUtils;
 
 import java.util.ArrayList;
 import java.util.Locale;
@@ -85,7 +87,9 @@ public class GalleryPreviewsScene extends ToolbarScene implements EasyRecyclerVi
     public void onCreate(@Nullable Bundle savedInstanceState) {
         super.onCreate(savedInstanceState);
 
-        mClient = EhApplication.getEhClient(getContext());
+        Context context = getContext2();
+        AssertUtils.assertNotNull(context);
+        mClient = EhApplication.getEhClient(context);
         if (savedInstanceState == null) {
             onInit();
         } else {
@@ -130,13 +134,17 @@ public class GalleryPreviewsScene extends ToolbarScene implements EasyRecyclerVi
         contentLayout.hideFastScroll();
         EasyRecyclerView recyclerView = contentLayout.getRecyclerView();
 
+        Context context = getContext2();
+        AssertUtils.assertNotNull(context);
+        Resources resources = context.getResources();
+
         mAdapter = new GalleryPreviewAdapter();
         recyclerView.setAdapter(mAdapter);
-        int columnWidth = getResources().getDimensionPixelOffset(R.dimen.preview_grid_column_width);
-        GridAutoSpanLayoutManager layoutManager = new GridAutoSpanLayoutManager(getContext(), columnWidth);
+        int columnWidth = resources.getDimensionPixelOffset(R.dimen.preview_grid_column_width);
+        GridAutoSpanLayoutManager layoutManager = new GridAutoSpanLayoutManager(context, columnWidth);
         layoutManager.setStrategy(GridAutoSpanLayoutManager.STRATEGY_SUITABLE_SIZE);
         recyclerView.setLayoutManager(layoutManager);
-        int padding = LayoutUtils.dp2pix(getContext(), 4);
+        int padding = LayoutUtils.dp2pix(context, 4);
         recyclerView.setPadding(padding, padding, padding, padding);
         recyclerView.setClipToPadding(false);
         recyclerView.addItemDecoration(new MarginItemDecoration(padding));
@@ -182,6 +190,11 @@ public class GalleryPreviewsScene extends ToolbarScene implements EasyRecyclerVi
 
     @Override
     public boolean onMenuItemClick(MenuItem item) {
+        Context context = getContext2();
+        if (null == context) {
+            return false;
+        }
+
         int id = item.getItemId();
         switch (id) {
             case R.id.action_go_to:
@@ -191,12 +204,12 @@ public class GalleryPreviewsScene extends ToolbarScene implements EasyRecyclerVi
                 int pages = mHelper.getPages();
                 if (pages > 0 && mHelper.canGoTo()) {
                     GoToDialogHelper helper = new GoToDialogHelper(pages, mHelper.getPageForTop());
-                    AlertDialog dialog = new AlertDialog.Builder(getContext()).setTitle(R.string.go_to)
-                            .setView(helper.getView())
+                    AlertDialog dialog = new AlertDialog.Builder(context).setTitle(R.string.go_to)
+                            .setView(R.layout.dialog_go_to)
                             .setPositiveButton(android.R.string.ok, null)
                             .create();
                     dialog.show();
-                    helper.setPositiveButtonClickListener(dialog);
+                    helper.setDialog(dialog);
                 }
                 return true;
         }
@@ -210,7 +223,7 @@ public class GalleryPreviewsScene extends ToolbarScene implements EasyRecyclerVi
 
     @Override
     public boolean onItemClick(EasyRecyclerView parent, View view, int position, long id) {
-        Context context = getContext();
+        Context context = getContext2();
         if (null != context && null != mHelper && null != mGalleryInfo) {
             GalleryPreview p = mHelper.getDataAt(position);
             Intent intent = new Intent(context, GalleryActivity.class);
@@ -237,9 +250,16 @@ public class GalleryPreviewsScene extends ToolbarScene implements EasyRecyclerVi
 
     private class GalleryPreviewAdapter extends RecyclerView.Adapter<GalleryPreviewHolder> {
 
+        private final LayoutInflater mInflater;
+
+        public GalleryPreviewAdapter() {
+            mInflater = getLayoutInflater2();
+            AssertUtils.assertNotNull(mInflater);
+        }
+
         @Override
         public GalleryPreviewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
-            return new GalleryPreviewHolder(getActivity().getLayoutInflater().inflate(R.layout.item_gallery_preview, parent, false));
+            return new GalleryPreviewHolder(mInflater.inflate(R.layout.item_gallery_preview, parent, false));
         }
 
         @Override
@@ -261,7 +281,8 @@ public class GalleryPreviewsScene extends ToolbarScene implements EasyRecyclerVi
 
         @Override
         protected void getPageData(final int taskId, int type, int page) {
-            if (null == mClient || null == mGalleryInfo) {
+            MainActivity activity = getActivity2();
+            if (null == activity || null == mClient || null == mGalleryInfo) {
                 onGetException(taskId, new EhException(getString(R.string.error_cannot_find_gallery)));
                 return;
             }
@@ -283,14 +304,14 @@ public class GalleryPreviewsScene extends ToolbarScene implements EasyRecyclerVi
             EhRequest request = new EhRequest();
             request.setMethod(EhClient.METHOD_GET_LARGE_PREVIEW_SET);
             request.setCallback(new GetLargePreviewSetListener(getContext(),
-                    ((StageActivity) getActivity()).getStageId(), getTag(), taskId, mGalleryInfo.gid, page));
+                    activity.getStageId(), getTag(), taskId, mGalleryInfo.gid, page));
             request.setArgs(url);
             mClient.execute(request);
         }
 
         @Override
         protected Context getContext() {
-            return GalleryPreviewsScene.this.getContext();
+            return GalleryPreviewsScene.this.getContext2();
         }
 
         @Override
@@ -387,35 +408,37 @@ public class GalleryPreviewsScene extends ToolbarScene implements EasyRecyclerVi
             DialogInterface.OnDismissListener {
 
         private final int mPages;
+        private final int mCurrentPage;
 
-        private final View mView;
-        private final Slider mSlider;
-
+        @Nullable
+        private Slider mSlider;
+        @Nullable
         private Dialog mDialog;
 
-        @SuppressLint("InflateParams")
         private GoToDialogHelper(int pages, int currentPage) {
             mPages = pages;
-            mView = getActivity().getLayoutInflater().inflate(R.layout.dialog_go_to, null);
-            ((TextView) mView.findViewById(R.id.start)).setText("1");
-            ((TextView) mView.findViewById(R.id.end)).setText(String.format(Locale.US, "%d", pages));
-            mSlider = (Slider) mView.findViewById(R.id.slider);
-            mSlider.setRange(1, pages);
-            mSlider.setProgress(currentPage + 1);
+            mCurrentPage = currentPage;
         }
 
-        public View getView() {
-            return mView;
-        }
-
-        public void setPositiveButtonClickListener(AlertDialog dialog) {
+        public void setDialog(@NonNull AlertDialog dialog) {
             mDialog = dialog;
+
+            ((TextView) ViewUtils.$$(dialog, R.id.start)).setText(String.format(Locale.US, "%d", 1));
+            ((TextView) ViewUtils.$$(dialog, R.id.end)).setText(String.format(Locale.US, "%d", mPages));
+            mSlider = (Slider) ViewUtils.$$(dialog, R.id.slider);
+            mSlider.setRange(1, mPages);
+            mSlider.setProgress(mCurrentPage + 1);
+
             dialog.getButton(AlertDialog.BUTTON_POSITIVE).setOnClickListener(this);
             dialog.setOnDismissListener(this);
         }
 
         @Override
         public void onClick(View v) {
+            if (null == mSlider) {
+                return;
+            }
+
             int page = mSlider.getProgress() - 1;
             if (page >= 0 && page < mPages && mHelper != null) {
                 mHelper.goTo(page);
@@ -431,6 +454,7 @@ public class GalleryPreviewsScene extends ToolbarScene implements EasyRecyclerVi
         @Override
         public void onDismiss(DialogInterface dialog) {
             mDialog = null;
+            mSlider = null;
         }
     }
 }

app/src/main/java/com/hippo/ehviewer/ui/scene/HistoryScene.java

@@ -18,6 +18,7 @@ package com.hippo.ehviewer.ui.scene;
 
 import android.content.Context;
 import android.content.DialogInterface;
+import android.content.res.Resources;
 import android.graphics.drawable.Drawable;
 import android.os.Bundle;
 import android.support.annotation.Nullable;
@@ -42,11 +43,11 @@ import com.hippo.ehviewer.ui.MainActivity;
 import com.hippo.rippleold.RippleSalon;
 import com.hippo.scene.Announcer;
 import com.hippo.scene.SceneFragment;
-import com.hippo.scene.StageActivity;
 import com.hippo.util.ApiHelper;
 import com.hippo.util.DrawableManager;
 import com.hippo.view.ViewTransition;
 import com.hippo.widget.recyclerview.GridAutoSpanLayoutManager;
+import com.hippo.yorozuya.AssertUtils;
 import com.hippo.yorozuya.ResourcesUtils;
 import com.hippo.yorozuya.ViewUtils;
 
@@ -82,12 +83,15 @@ public class HistoryScene extends ToolbarScene
         TextView tip = (TextView) ViewUtils.$$(view, R.id.tip);
         mViewTransition = new ViewTransition(content, tip);
 
-        Drawable drawable = DrawableManager.getDrawable(getContext(), R.drawable.big_history);
+        Context context = getContext2();
+        AssertUtils.assertNotNull(context);
+
+        Drawable drawable = DrawableManager.getDrawable(context, R.drawable.big_history);
         drawable.setBounds(0, 0, drawable.getIntrinsicWidth(), drawable.getIntrinsicHeight());
         tip.setCompoundDrawables(null, drawable, null, null);
 
         mList = EhDB.getHistoryLazyList();
-        GridAutoSpanLayoutManager layoutManager = new GridAutoSpanLayoutManager(getContext(), 0);
+        GridAutoSpanLayoutManager layoutManager = new GridAutoSpanLayoutManager(context, 0);
         recyclerView.setLayoutManager(layoutManager);
         recyclerView.setSelector(RippleSalon.generateRippleDrawable(false));
         recyclerView.setDrawSelectorOnTop(true);
@@ -95,14 +99,14 @@ public class HistoryScene extends ToolbarScene
         recyclerView.setClipToPadding(false);
         recyclerView.setOnItemClickListener(this);
         recyclerView.setOnItemLongClickListener(this);
-        mAdapter = new HistoryAdapter(LayoutInflater.from(getContext()),
-                getContext(), recyclerView, layoutManager, Settings.getListMode());
+        mAdapter = new HistoryAdapter(getLayoutInflater2(), getResources2(),
+                recyclerView, layoutManager, Settings.getListMode());
         recyclerView.setAdapter(mAdapter);
         mAdapter.register();
 
         fastScroller.attachToRecyclerView(recyclerView);
         HandlerDrawable handlerDrawable = new HandlerDrawable();
-        handlerDrawable.setColor(ResourcesUtils.getAttrColor(getContext(), R.attr.colorAccent));
+        handlerDrawable.setColor(ResourcesUtils.getAttrColor(context, R.attr.colorAccent));
         fastScroller.setHandlerDrawable(handlerDrawable);
 
         if (null != mList && mList.size() > 0) {
@@ -163,24 +167,26 @@ public class HistoryScene extends ToolbarScene
 
     @Override
     public boolean onItemLongClick(EasyRecyclerView parent, View view, int position, long id) {
-        if (null == mList) {
+        final Context context = getContext2();
+        final MainActivity activity = getActivity2();
+        if (null == context || null == activity || null == mList) {
             return false;
         }
 
         final GalleryInfo gi = mList.get(position);
-        new AlertDialog.Builder(getContext())
+        new AlertDialog.Builder(context)
                 .setTitle(EhUtils.getSuitableTitle(gi))
                 .setItems(R.array.gallery_list_menu_entries, new DialogInterface.OnClickListener() {
                     @Override
                     public void onClick(DialogInterface dialog, int which) {
                         switch (which) {
                             case 0: // Download
-                                CommonOperations.startDownload((MainActivity) getActivity(), gi, false);
+                                CommonOperations.startDownload(activity, gi, false);
                                 break;
                             case 1: // Favorites
-                                CommonOperations.addToFavorites(getActivity(), gi,
-                                        new addToFavoriteListener(getContext(),
-                                                ((StageActivity) getActivity()).getStageId(), getTag()));
+                                CommonOperations.addToFavorites(activity, gi,
+                                        new addToFavoriteListener(context,
+                                                activity.getStageId(), getTag()));
                                 break;
                         }
                     }
@@ -190,9 +196,9 @@ public class HistoryScene extends ToolbarScene
 
     private class HistoryAdapter extends GalleryAdapter {
 
-        public HistoryAdapter(LayoutInflater inflater, Context context,
+        public HistoryAdapter(LayoutInflater inflater, Resources resources,
                 RecyclerView recyclerView, GridAutoSpanLayoutManager layoutManager, int type) {
-            super(inflater, context, recyclerView, layoutManager, type);
+            super(inflater, resources, recyclerView, layoutManager, type);
         }
 
         @Nullable

app/src/main/java/com/hippo/ehviewer/ui/scene/ProgressScene.java

@@ -30,12 +30,14 @@ import com.hippo.ehviewer.EhApplication;
 import com.hippo.ehviewer.R;
 import com.hippo.ehviewer.client.EhClient;
 import com.hippo.ehviewer.client.EhRequest;
+import com.hippo.ehviewer.ui.MainActivity;
 import com.hippo.scene.Announcer;
 import com.hippo.scene.SceneFragment;
-import com.hippo.scene.StageActivity;
 import com.hippo.util.DrawableManager;
 import com.hippo.util.ExceptionUtils;
 import com.hippo.view.ViewTransition;
+import com.hippo.yorozuya.AssertUtils;
+import com.hippo.yorozuya.ViewUtils;
 
 /**
  * Only show a progress with jobs in background
@@ -61,7 +63,9 @@ public final class ProgressScene extends BaseScene implements View.OnClickListen
     private String mPToken;
     private int mPage;
 
+    @Nullable
     private TextView mTip;
+    @Nullable
     private ViewTransition mViewTransition;
 
     @Override
@@ -81,6 +85,12 @@ public final class ProgressScene extends BaseScene implements View.OnClickListen
     }
 
     private boolean doJobs() {
+        Context context = getContext2();
+        MainActivity activity = getActivity2();
+        if (null == context || null == activity) {
+            return false;
+        }
+
         if (ACTION_GALLERY_TOKEN.equals(mAction)) {
             if (mGid == -1 || mPToken == null || mPage == -1) {
                 return false;
@@ -89,9 +99,9 @@ public final class ProgressScene extends BaseScene implements View.OnClickListen
             EhRequest request = new EhRequest()
                     .setMethod(EhClient.METHOD_GET_GALLERY_TOKEN)
                     .setArgs(mGid, mPToken, mPage)
-                    .setCallback(new GetGalleryTokenListener(getContext(),
-                            ((StageActivity) getActivity()).getStageId(), getTag()));
-            EhApplication.getEhClient(getContext()).execute(request);
+                    .setCallback(new GetGalleryTokenListener(context,
+                            activity.getStageId(), getTag()));
+            EhApplication.getEhClient(context).execute(request);
             return true;
         }
         return false;
@@ -155,10 +165,13 @@ public final class ProgressScene extends BaseScene implements View.OnClickListen
     public View onCreateView(LayoutInflater inflater,
             @Nullable ViewGroup container, @Nullable Bundle savedInstanceState) {
         View view = inflater.inflate(R.layout.scene_progress, container, false);
-        View progress = view.findViewById(R.id.progress);
-        mTip = (TextView) view.findViewById(R.id.tip);
+        View progress = ViewUtils.$$(view, R.id.progress);
+        mTip = (TextView) ViewUtils.$$(view, R.id.tip);
 
-        Drawable drawable = DrawableManager.getDrawable(getContext(), R.drawable.big_weird_face);
+        Context context = getContext2();
+        AssertUtils.assertNotNull(context);
+
+        Drawable drawable = DrawableManager.getDrawable(context, R.drawable.big_weird_face);
         drawable.setBounds(0, 0, drawable.getIntrinsicWidth(), drawable.getIntrinsicHeight());
         mTip.setCompoundDrawables(null, drawable, null, null);
         mTip.setOnClickListener(this);
@@ -175,13 +188,23 @@ public final class ProgressScene extends BaseScene implements View.OnClickListen
         return view;
     }
 
+    @Override
+    public void onDestroyView() {
+        super.onDestroyView();
+
+        mTip = null;
+        mViewTransition = null;
+    }
+
     @Override
     public void onClick(View v) {
         if (mTip == v) {
             if (doJobs()) {
                 mValid = true;
                 // Show progress
-                mViewTransition.showView(0, true);
+                if (null != mViewTransition) {
+                    mViewTransition.showView(0, true);
+                }
             }
         }
     }
@@ -198,10 +221,12 @@ public final class ProgressScene extends BaseScene implements View.OnClickListen
 
     private void onGetGalleryTokenFailure(Exception e) {
         mValid = false;
-        mError = ExceptionUtils.getReadableString(getContext(), e);
 
-        if (isViewCreated()) {
+        Context context = getContext2();
+
+        if (null != context && null != mViewTransition && null != mTip) {
             // Show tip
+            mError = ExceptionUtils.getReadableString(context, e);
             mViewTransition.showView(1);
             mTip.setText(mError);
         }

app/src/main/java/com/hippo/ehviewer/ui/scene/QuickSearchScene.java

@@ -16,6 +16,7 @@
 
 package com.hippo.ehviewer.ui.scene;
 
+import android.content.Context;
 import android.content.DialogInterface;
 import android.graphics.drawable.Drawable;
 import android.graphics.drawable.NinePatchDrawable;
@@ -48,6 +49,7 @@ import com.hippo.ehviewer.R;
 import com.hippo.ehviewer.dao.QuickSearch;
 import com.hippo.util.DrawableManager;
 import com.hippo.view.ViewTransition;
+import com.hippo.yorozuya.AssertUtils;
 import com.hippo.yorozuya.ViewUtils;
 
 import java.util.List;
@@ -91,7 +93,10 @@ public final class QuickSearchScene extends ToolbarScene {
         TextView tip = (TextView) ViewUtils.$$(view, R.id.tip);
         mViewTransition = new ViewTransition(recyclerView, tip);
 
-        Drawable drawable = DrawableManager.getDrawable(getContext(), R.drawable.big_search);
+        Context context = getContext2();
+        AssertUtils.assertNotNull(context);
+
+        Drawable drawable = DrawableManager.getDrawable(context, R.drawable.big_search);
         drawable.setBounds(0, 0, drawable.getIntrinsicWidth(), drawable.getIntrinsicHeight());
         tip.setCompoundDrawables(null, drawable, null, null);
         tip.setText(R.string.no_quick_search);
@@ -103,7 +108,7 @@ public final class QuickSearchScene extends ToolbarScene {
         // drag & drop manager
         RecyclerViewDragDropManager dragDropManager = new RecyclerViewDragDropManager();
         dragDropManager.setDraggingItemShadowDrawable(
-                (NinePatchDrawable) getResources().getDrawable(R.drawable.shadow_8dp));
+                (NinePatchDrawable) context.getResources().getDrawable(R.drawable.shadow_8dp));
         // swipe manager
         RecyclerViewSwipeManager swipeManager = new RecyclerViewSwipeManager();
         RecyclerView.Adapter adapter = new QuickSearchAdapter();
@@ -114,7 +119,7 @@ public final class QuickSearchScene extends ToolbarScene {
         final GeneralItemAnimator animator = new SwipeDismissItemAnimator();
         animator.setSupportsChangeAnimations(false);
         recyclerView.hasFixedSize();
-        recyclerView.setLayoutManager(new LinearLayoutManager(getContext()));
+        recyclerView.setLayoutManager(new LinearLayoutManager(context));
         recyclerView.setAdapter(adapter);
         recyclerView.setItemAnimator(animator);
         guardManager.attachRecyclerView(recyclerView);
@@ -181,10 +186,16 @@ public final class QuickSearchScene extends ToolbarScene {
             implements DraggableItemAdapter<QuickSearchHolder>,
             SwipeableItemAdapter<QuickSearchHolder> {
 
+        private final LayoutInflater mInflater;
+
+        public QuickSearchAdapter() {
+            mInflater = getLayoutInflater2();
+            AssertUtils.assertNotNull(mInflater);
+        }
+
         @Override
         public QuickSearchHolder onCreateViewHolder(ViewGroup parent, int viewType) {
-            return new QuickSearchHolder(getActivity().getLayoutInflater()
-                    .inflate(R.layout.item_label_list, parent, false));
+            return new QuickSearchHolder(mInflater.inflate(R.layout.item_label_list, parent, false));
         }
 
         @Override
@@ -269,14 +280,15 @@ public final class QuickSearchScene extends ToolbarScene {
         protected void onPerformAction() {
             super.onPerformAction();
 
+            Context context = getContext2();
             final List<QuickSearch> quickSearchList = mQuickSearchList;
-            if (quickSearchList == null || mPosition < 0 || mPosition >= quickSearchList.size()) {
+            if (null == context || null == quickSearchList || mPosition < 0 || mPosition >= quickSearchList.size()) {
                 return;
             }
 
             final QuickSearch quickSearch = quickSearchList.get(mPosition);
 
-            new AlertDialog.Builder(getContext())
+            new AlertDialog.Builder(context)
                     .setTitle(R.string.delete_quick_search_title)
                     .setMessage(getString(R.string.delete_quick_search_message, quickSearch.name))
                     .setPositiveButton(android.R.string.ok, new DialogInterface.OnClickListener() {

app/src/main/java/com/hippo/ehviewer/ui/scene/SignInScene.java

@@ -44,8 +44,6 @@ import com.hippo.ehviewer.ui.MainActivity;
 import com.hippo.rippleold.RippleSalon;
 import com.hippo.scene.Announcer;
 import com.hippo.scene.SceneFragment;
-import com.hippo.scene.StageActivity;
-import com.hippo.util.ActivityHelper;
 import com.hippo.util.ExceptionUtils;
 import com.hippo.yorozuya.AssertUtils;
 import com.hippo.yorozuya.ViewUtils;
@@ -148,7 +146,9 @@ public final class SignInScene extends BaseScene implements EditText.OnEditorAct
         RippleSalon.addRipple(mRegister, true);
         RippleSalon.addRipple(mSignIn, true);
 
-        EhApplication application = (EhApplication) getContext().getApplicationContext();
+        Context context = getContext2();
+        AssertUtils.assertNotNull(container);
+        EhApplication application = (EhApplication) context.getApplicationContext();
         if (application.containGlobalStuff(mRequestId)) {
             // request exist
             showProgress(false);
@@ -163,7 +163,7 @@ public final class SignInScene extends BaseScene implements EditText.OnEditorAct
 
         // Show IME
         if (mProgress != null && View.INVISIBLE != mProgress.getVisibility()) {
-            ActivityHelper.showSoftInput(getActivity(), mUsername);
+            showSoftInput(mUsername);
         }
     }
 
@@ -215,8 +215,13 @@ public final class SignInScene extends BaseScene implements EditText.OnEditorAct
 
     @Override
     public void onClick(View v) {
+        MainActivity activity = getActivity2();
+        if (null == activity) {
+            return;
+        }
+
         if (mRegister == v) {
-            UrlOpener.openUrl(getActivity(), EhUrl.URL_REGISTER, false, true);
+            UrlOpener.openUrl(activity, EhUrl.URL_REGISTER, false, true);
         } else if (mSignIn == v) {
             signIn();
         } else if (mSignInViaWebView == v) {
@@ -243,7 +248,9 @@ public final class SignInScene extends BaseScene implements EditText.OnEditorAct
     }
 
     private void signIn() {
-        if (null == mUsername || null == mPassword || null == mUsernameLayout ||
+        Context context = getContext2();
+        MainActivity activity = getActivity2();
+        if (null == context || null == activity || null == mUsername || null == mPassword || null == mUsernameLayout ||
                 null == mPasswordLayout) {
             return;
         }
@@ -265,44 +272,57 @@ public final class SignInScene extends BaseScene implements EditText.OnEditorAct
             mPasswordLayout.setError(null);
         }
 
-        ActivityHelper.hideSoftInput(getActivity());
+        hideSoftInput();
         showProgress(true);
 
         // Clean up for sign in
-        EhUtils.signOut(getContext());
+        EhUtils.signOut(context);
 
-        EhCallback callback = new SignInListener(getContext(),
-                ((StageActivity) getActivity()).getStageId(), getTag());
-        mRequestId = ((EhApplication) getContext().getApplicationContext()).putGlobalStuff(callback);
+        EhCallback callback = new SignInListener(context,
+                activity.getStageId(), getTag());
+        mRequestId = ((EhApplication) context.getApplicationContext()).putGlobalStuff(callback);
         EhRequest request = new EhRequest()
                 .setMethod(EhClient.METHOD_SIGN_IN)
                 .setArgs(username, password)
                 .setCallback(callback);
-        EhApplication.getEhClient(getContext()).execute(request);
+        EhApplication.getEhClient(context).execute(request);
     }
 
     private void getProfile() {
-        ActivityHelper.hideSoftInput(getActivity());
+        Context context = getContext2();
+        MainActivity activity = getActivity2();
+        if (null == context || null == activity) {
+            return;
+        }
+
+        hideSoftInput();
         showProgress(true);
 
-        EhCallback callback = new GetProfileListener(getContext(),
-                ((StageActivity) getActivity()).getStageId(), getTag());
-        mRequestId = ((EhApplication) getContext().getApplicationContext()).putGlobalStuff(callback);
+        EhCallback callback = new GetProfileListener(context,
+                activity.getStageId(), getTag());
+        mRequestId = ((EhApplication) context.getApplicationContext()).putGlobalStuff(callback);
         EhRequest request = new EhRequest()
                 .setMethod(EhClient.METHOD_GET_PROFILE)
                 .setCallback(callback);
-        EhApplication.getEhClient(getContext()).execute(request);
+        EhApplication.getEhClient(context).execute(request);
     }
 
     private void redirectTo() {
         Settings.putNeedSignIn(false);
-        ((MainActivity) getActivity()).startSceneForCheckStep(
-                MainActivity.CHECK_STEP_SIGN_IN, getArguments());
+        MainActivity activity = getActivity2();
+        if (null != activity) {
+            activity.startSceneForCheckStep(MainActivity.CHECK_STEP_SIGN_IN, getArguments());
+        }
         finish();
     }
 
     private void whetherToSkip() {
-        new AlertDialog.Builder(getContext())
+        Context context = getContext2();
+        if (null == context) {
+            return;
+        }
+
+        new AlertDialog.Builder(context)
                 .setTitle(R.string.sign_in_failed)
                 .setMessage(R.string.sign_in_failed_plain)
                 .setNegativeButton(android.R.string.cancel, null)
@@ -311,7 +331,12 @@ public final class SignInScene extends BaseScene implements EditText.OnEditorAct
     }
 
     public void onSignInSuccess() {
-        if (EhApplication.getEhCookieStore(getContext()).hasSignedIn()) {
+        Context context = getContext2();
+        if (null == context) {
+            return;
+        }
+
+        if (EhApplication.getEhCookieStore(context).hasSignedIn()) {
             getProfile();
         } else {
             hideProgress();
@@ -320,7 +345,12 @@ public final class SignInScene extends BaseScene implements EditText.OnEditorAct
     }
 
     public void onSignInFailure(Exception e) {
-        Toast.makeText(getContext(), ExceptionUtils.getReadableString(getContext(), e),
+        Context context = getContext2();
+        if (null == context) {
+            return;
+        }
+
+        Toast.makeText(context, ExceptionUtils.getReadableString(context, e),
                 Toast.LENGTH_SHORT).show();
         hideProgress();
         whetherToSkip();
@@ -332,7 +362,12 @@ public final class SignInScene extends BaseScene implements EditText.OnEditorAct
     }
 
     public void onGetProfileFailure(Exception e) {
-        Toast.makeText(getContext(), ExceptionUtils.getReadableString(getContext(), e),
+        Context context = getContext2();
+        if (null == context) {
+            return;
+        }
+
+        Toast.makeText(context, ExceptionUtils.getReadableString(context, e),
                 Toast.LENGTH_SHORT).show();
         hideProgress();
         whetherToSkip();

app/src/main/java/com/hippo/ehviewer/ui/scene/WarningScene.java

@@ -80,8 +80,10 @@ public final class WarningScene extends BaseScene implements View.OnClickListene
             Settings.putShowWarning(false);
 
             // Start new scene and finish it self
-            ((MainActivity) getActivity()).startSceneForCheckStep(
-                    MainActivity.CHECK_STEP_WARNING, getArguments());
+            MainActivity activity = getActivity2();
+            if (null != activity) {
+                activity.startSceneForCheckStep(MainActivity.CHECK_STEP_WARNING, getArguments());
+            }
             finish();
         }
     }

app/src/main/java/com/hippo/ehviewer/ui/scene/WebViewSignInScene.java

@@ -31,6 +31,7 @@ import com.hippo.ehviewer.EhApplication;
 import com.hippo.ehviewer.client.EhCookieStore;
 import com.hippo.ehviewer.client.EhUrl;
 import com.hippo.ehviewer.client.EhUtils;
+import com.hippo.yorozuya.AssertUtils;
 
 import java.util.ArrayList;
 import java.util.Collections;
@@ -58,9 +59,12 @@ public class WebViewSignInScene extends BaseScene {
     @SuppressLint("SetJavaScriptEnabled")
     public View onCreateView(LayoutInflater inflater,
             @Nullable ViewGroup container, @Nullable Bundle savedInstanceState) {
-        EhUtils.signOut(getContext());
+        Context context = getContext2();
+        AssertUtils.assertNotNull(context);
+
+        EhUtils.signOut(context);
         CookieManager.getInstance().removeAllCookie();
-        mWebView = new WebView(getContext());
+        mWebView = new WebView(context);
         mWebView.getSettings().setJavaScriptEnabled(true);
         mWebView.setWebViewClient(new LoginWebViewClient());
         mWebView.loadUrl(EhUrl.URL_SIGN_IN);
@@ -106,7 +110,7 @@ public class WebViewSignInScene extends BaseScene {
 
         @Override
         public void onPageFinished(WebView view, String url) {
-            Context context = getContext();
+            Context context = getContext2();
             if (context == null) {
                 return;
             }

app/src/main/java/com/hippo/scene/SceneFragment.java

@@ -97,14 +97,18 @@ public class SceneFragment extends Fragment {
     }
 
     @Override
+    @SuppressWarnings("deprecation")
     public void onViewCreated(View view, @Nullable Bundle savedInstanceState) {
         super.onViewCreated(view, savedInstanceState);
 
         view.setTag(R.id.fragment_tag, getTag());
-        view.setBackgroundColor(getContext().getResources().getColor(R.color.background_light));
+        view.setBackgroundColor(getResources().getColor(R.color.background_light));
 
         // Notify
-        ((StageActivity) getActivity()).onSceneViewCreated(this, savedInstanceState);
+        FragmentActivity activity = getActivity();
+        if (activity instanceof StageActivity) {
+            ((StageActivity) activity).onSceneViewCreated(this, savedInstanceState);
+        }
     }
 
     @Override
@@ -112,14 +116,20 @@ public class SceneFragment extends Fragment {
         super.onDestroyView();
 
         // Notify
-        ((StageActivity) getActivity()).onSceneViewDestroyed(this);
+        FragmentActivity activity = getActivity();
+        if (activity instanceof StageActivity) {
+            ((StageActivity) activity).onSceneViewDestroyed(this);
+        }
     }
 
     @Override
     public void onDestroy() {
         super.onDestroy();
 
-        ((StageActivity) getActivity()).onSceneDestroyed(this);
+        FragmentActivity activity = getActivity();
+        if (activity instanceof StageActivity) {
+            ((StageActivity) activity).onSceneDestroyed(this);
+        }
     }
 
     void addRequest(String requestSceneTag, int requestCode) {

app/src/main/java/com/hippo/text/LinkMovementMethod2.java

@@ -16,11 +16,11 @@
 
 package com.hippo.text;
 
-import android.app.Activity;
 import android.text.Layout;
 import android.text.NoCopySpan;
 import android.text.Selection;
 import android.text.Spannable;
+import android.text.method.MovementMethod;
 import android.text.method.ScrollingMovementMethod;
 import android.text.style.ClickableSpan;
 import android.text.style.URLSpan;
@@ -40,11 +40,7 @@ public class LinkMovementMethod2 extends ScrollingMovementMethod {
     private static final int UP = 2;
     private static final int DOWN = 3;
 
-    private final Activity mActivity;
-
-    public LinkMovementMethod2(Activity activity) {
-        mActivity = activity;
-    }
+    private LinkMovementMethod2() {}
 
     @Override
     public boolean canSelectArbitrarily() {
@@ -227,7 +223,7 @@ public class LinkMovementMethod2 extends ScrollingMovementMethod {
                 if (action == MotionEvent.ACTION_UP) {
                     ClickableSpan span = link[0];
                     if (span instanceof URLSpan) {
-                        UrlOpener.openUrl(mActivity, ((URLSpan) span).getURL(), true, true);
+                        UrlOpener.openUrl(widget.getContext(), ((URLSpan) span).getURL(), true, true);
                     } else {
                         span.onClick(widget);
                     }
@@ -263,5 +259,13 @@ public class LinkMovementMethod2 extends ScrollingMovementMethod {
         }
     }
 
+    public static MovementMethod getInstance() {
+        if (sInstance == null)
+            sInstance = new LinkMovementMethod2();
+
+        return sInstance;
+    }
+
+    private static LinkMovementMethod2 sInstance;
     private static final Object FROM_BELOW = new NoCopySpan.Concrete();
 }