Add scrollToPositionProperly

app/src/main/java/com/hippo/ehviewer/widget/ContentLayout.java

@@ -221,6 +221,14 @@ public class ContentLayout extends FrameLayout {
             }
         };
 
+        private LayoutManagerUtils.OnScrollToPositionListener mOnScrollToPositionListener =
+                new LayoutManagerUtils.OnScrollToPositionListener() {
+                    @Override
+                    public void onScrollToPosition() {
+                        ContentHelper.this.onScrollToPosition();
+                    }
+                };
+
         public ContentHelper(Context context) {
             mContext = context;
             mData = new ArrayList<>();
@@ -352,7 +360,7 @@ public class ContentLayout extends FrameLayout {
                             mLastIndex += pageVolume;
 
                             mRecyclerView.stopScroll();
-                            LayoutManagerUtils.smoothScrollToPosition(mLayoutManager, mContext, mFirstIndex - 1, 100);
+                            LayoutManagerUtils.scrollToPositionProperly(mLayoutManager, mContext, mFirstIndex - 1, mOnScrollToPositionListener);
                         } else {
                             mCurrentPage = mFirstPage;
                             mFirstIndex = 0;
@@ -466,8 +474,8 @@ public class ContentLayout extends FrameLayout {
             if (mViewTransition.getShownViewIndex() == 0) {
                 // Go to top
                 mRecyclerView.stopScroll();
-                LayoutManagerUtils.scrollToPositionWithOffset(mLayoutManager, 0, 0);
-                onScrollToPosition();
+                LayoutManagerUtils.scrollToPositionProperly(mLayoutManager,
+                        mContext, 0, mOnScrollToPositionListener);
                 // Show header refresh
                 mRefreshLayout.setFooterRefreshing(false);
                 mRefreshLayout.setHeaderRefreshing(true);

app/src/main/java/com/hippo/util/LayoutManagerUtils.java

@@ -78,6 +78,28 @@ public final class LayoutManagerUtils {
         layoutManager.startSmoothScroll(smoothScroller);
     }
 
+    public static void scrollToPositionProperly(final RecyclerView.LayoutManager layoutManager,
+            final Context context, final int position, final OnScrollToPositionListener listener) {
+        AppHandler.getInstance().post(new Runnable() {
+            @Override
+            public void run() {
+                int first = getFirstVisibleItemPostion(layoutManager);
+                int last = getLastVisibleItemPostion(layoutManager);
+                int offset = Math.abs(position - first);
+                int max = last - first;
+                if (offset < max && max > 0) {
+                    smoothScrollToPosition(layoutManager, context, position,
+                            MathUtils.lerp(100, 25, (offset / max)));
+                } else {
+                    scrollToPositionWithOffset(layoutManager, position, 0);
+                    if (listener != null) {
+                        listener.onScrollToPosition();
+                    }
+                }
+            }
+        });
+    }
+
     public static int getFirstVisibleItemPostion(RecyclerView.LayoutManager layoutManager) {
         if (layoutManager instanceof LinearLayoutManager) {
             return ((LinearLayoutManager) layoutManager).findFirstVisibleItemPosition();
@@ -101,4 +123,8 @@ public final class LayoutManagerUtils {
                     layoutManager.getClass().getName());
         }
     }
+
+    public interface OnScrollToPositionListener {
+        void onScrollToPosition();
+    }
 }