Convert MarginItemDecoration, SimpleSmoothScroller and WindowInsetsAnimationHelper to kotlin

app/src/main/java/com/hippo/ehviewer/ui/legacy/LayoutManagerUtils.kt

@@ -59,7 +59,7 @@ object LayoutManagerUtils {
     @JvmOverloads
     fun smoothScrollToPosition(
         layoutManager: RecyclerView.LayoutManager,
-        context: Context?,
+        context: Context,
         position: Int,
         millisecondsPerInch: Int = -1,
     ) {
@@ -106,7 +106,7 @@ object LayoutManagerUtils {
 
     fun scrollToPositionProperly(
         layoutManager: RecyclerView.LayoutManager,
-        context: Context?,
+        context: Context,
         position: Int,
         listener: OnScrollToPositionListener?,
     ) {

app/src/main/java/com/hippo/ehviewer/ui/legacy/MarginItemDecoration.kt

@@ -13,31 +13,37 @@
  * See the License for the specific language governing permissions and
  * limitations under the License.
  */
+package com.hippo.ehviewer.ui.legacy
 
-package com.hippo.ehviewer.ui.legacy;
+import android.graphics.Rect
+import android.view.View
+import androidx.recyclerview.widget.RecyclerView
+import androidx.recyclerview.widget.RecyclerView.ItemDecoration
 
-import android.graphics.Rect;
-import android.view.View;
+class MarginItemDecoration(
+    margin: Int,
+    paddingLeft: Int,
+    paddingTop: Int,
+    paddingRight: Int,
+    paddingBottom: Int,
+) : ItemDecoration() {
+    private var mMargin = 0
+    private var mPaddingLeft = 0
+    private var mPaddingTop = 0
+    private var mPaddingRight = 0
+    private var mPaddingBottom = 0
 
-import androidx.recyclerview.widget.RecyclerView;
-
-public class MarginItemDecoration extends RecyclerView.ItemDecoration {
-
-    private int mMargin;
-    private int mPaddingLeft;
-    private int mPaddingTop;
-    private int mPaddingRight;
-    private int mPaddingBottom;
-
-    public MarginItemDecoration(int margin, int paddingLeft, int paddingTop,
-                                int paddingRight, int paddingBottom) {
-        setMargin(margin, paddingLeft, paddingTop, paddingRight, paddingBottom);
+    init {
+        setMargin(margin, paddingLeft, paddingTop, paddingRight, paddingBottom)
     }
 
-    @Override
-    public void getItemOffsets(Rect outRect, View view,
-                               RecyclerView parent, RecyclerView.State state) {
-        outRect.set(mMargin, mMargin, mMargin, mMargin);
+    override fun getItemOffsets(
+        outRect: Rect,
+        view: View,
+        parent: RecyclerView,
+        state: RecyclerView.State,
+    ) {
+        outRect[mMargin, mMargin, mMargin] = mMargin
     }
 
     /**
@@ -47,17 +53,22 @@ public class MarginItemDecoration extends RecyclerView.ItemDecoration {
      * @param paddingRight  gap between RecyclerView right and right item right
      * @param paddingBottom gap between RecyclerView bottom and bottom item bottom
      */
-    public void setMargin(int margin, int paddingLeft, int paddingTop,
-                          int paddingRight, int paddingBottom) {
-        int halfMargin = margin / 2;
-        mMargin = halfMargin;
-        mPaddingLeft = paddingLeft - halfMargin;
-        mPaddingTop = paddingTop - halfMargin;
-        mPaddingRight = paddingRight - halfMargin;
-        mPaddingBottom = paddingBottom - halfMargin;
+    fun setMargin(
+        margin: Int,
+        paddingLeft: Int,
+        paddingTop: Int,
+        paddingRight: Int,
+        paddingBottom: Int,
+    ) {
+        val halfMargin = margin / 2
+        mMargin = halfMargin
+        mPaddingLeft = paddingLeft - halfMargin
+        mPaddingTop = paddingTop - halfMargin
+        mPaddingRight = paddingRight - halfMargin
+        mPaddingBottom = paddingBottom - halfMargin
     }
 
-    public void applyPaddings(View view) {
-        view.setPadding(mPaddingLeft, mPaddingTop, mPaddingRight, mPaddingBottom);
+    fun applyPaddings(view: View) {
+        view.setPadding(mPaddingLeft, mPaddingTop, mPaddingRight, mPaddingBottom)
     }
 }

app/src/main/java/com/hippo/ehviewer/ui/legacy/SimpleSmoothScroller.kt

@@ -13,28 +13,26 @@
  * See the License for the specific language governing permissions and
  * limitations under the License.
  */
+package com.hippo.ehviewer.ui.legacy
 
-package com.hippo.ehviewer.ui.legacy;
+import android.content.Context
+import androidx.recyclerview.widget.LinearSmoothScroller
+import kotlin.math.abs
+import kotlin.math.ceil
 
-import android.content.Context;
+abstract class SimpleSmoothScroller(context: Context, millisecondsPerInch: Float) :
+    LinearSmoothScroller(context) {
+    private val mMillisecondsPerPx: Float
 
-import androidx.recyclerview.widget.LinearSmoothScroller;
-
-public abstract class SimpleSmoothScroller extends LinearSmoothScroller {
-
-    private final float mMillisecondsPerPx;
-
-    public SimpleSmoothScroller(Context context, float millisecondsPerInch) {
-        super(context);
-        mMillisecondsPerPx = millisecondsPerInch / context.getResources().getDisplayMetrics().densityDpi;
+    init {
+        mMillisecondsPerPx = millisecondsPerInch / context.resources.displayMetrics.densityDpi
     }
 
-    @Override
-    protected int calculateTimeForScrolling(int dx) {
-        if (mMillisecondsPerPx <= 0) {
-            return super.calculateTimeForScrolling(dx);
+    override fun calculateTimeForScrolling(dx: Int): Int {
+        return if (mMillisecondsPerPx <= 0) {
+            super.calculateTimeForScrolling(dx)
         } else {
-            return (int) Math.ceil(Math.abs(dx) * mMillisecondsPerPx);
+            ceil((abs(dx) * mMillisecondsPerPx).toDouble()).toInt()
         }
     }
 }

app/src/main/java/com/hippo/ehviewer/ui/legacy/WindowInsetsAnimationHelper.kt

@@ -15,95 +15,81 @@
  * You should have received a copy of the GNU General Public License along with EhViewer.
  * If not, see <https://www.gnu.org/licenses/>.
  */
+package com.hippo.ehviewer.ui.legacy
 
-package com.hippo.ehviewer.ui.legacy;
+import android.view.View
+import androidx.core.view.WindowInsetsAnimationCompat
+import androidx.core.view.WindowInsetsAnimationCompat.BoundsCompat
+import androidx.core.view.WindowInsetsCompat
+import com.google.android.material.math.MathUtils
 
-import android.view.View;
+class WindowInsetsAnimationHelper(dispatchMode: Int, vararg views: View) :
+    WindowInsetsAnimationCompat.Callback(dispatchMode) {
+    private val views: Array<View>
+    private val startPaddings = HashMap<View, Int>()
+    private val endPaddings = HashMap<View, Int>()
+    var animation: WindowInsetsAnimationCompat? = null
 
-import androidx.annotation.NonNull;
-import androidx.core.view.WindowInsetsAnimationCompat;
-import androidx.core.view.WindowInsetsCompat;
-
-import com.google.android.material.math.MathUtils;
-
-import java.util.HashMap;
-import java.util.List;
-
-public class WindowInsetsAnimationHelper extends WindowInsetsAnimationCompat.Callback {
-    private final View[] views;
-    private final HashMap<View, Integer> startPaddings = new HashMap<>();
-    private final HashMap<View, Integer> endPaddings = new HashMap<>();
-    WindowInsetsAnimationCompat animation;
-
-    public WindowInsetsAnimationHelper(int dispatchMode, View... views) {
-        super(dispatchMode);
-        this.views = views;
+    init {
+        this.views = arrayOf(*views)
     }
 
-    @Override
-    public void onPrepare(@NonNull WindowInsetsAnimationCompat animation) {
-        super.onPrepare(animation);
-        this.animation = animation;
-        for (View view : views) {
-            if (view == null) {
-                continue;
-            }
-            startPaddings.put(view, view.getPaddingBottom());
+    override fun onPrepare(animation: WindowInsetsAnimationCompat) {
+        super.onPrepare(animation)
+        this.animation = animation
+        for (view in views) {
+            startPaddings[view] = view.paddingBottom
         }
     }
 
-    @NonNull
-    @Override
-    public WindowInsetsAnimationCompat.BoundsCompat onStart(@NonNull WindowInsetsAnimationCompat animation, @NonNull WindowInsetsAnimationCompat.BoundsCompat bounds) {
-        this.animation = animation;
-        for (View view : views) {
-            if (view == null) {
-                continue;
-            }
-            endPaddings.put(view, view.getPaddingBottom());
-            int startPadding = startPaddings.containsKey(view) ? startPaddings.get(view) : 0;
-            view.setTranslationY(-(startPadding - view.getPaddingBottom()));
+    override fun onStart(
+        animation: WindowInsetsAnimationCompat,
+        bounds: BoundsCompat,
+    ): BoundsCompat {
+        this.animation = animation
+        for (view in views) {
+            endPaddings[view] = view.paddingBottom
+            val startPadding = if (startPaddings.containsKey(view)) startPaddings[view]!! else 0
+            view.translationY = -(startPadding - view.paddingBottom).toFloat()
         }
-        return bounds;
+        return bounds
     }
 
-    @NonNull
-    @Override
-    public WindowInsetsCompat onProgress(@NonNull WindowInsetsCompat insets, @NonNull List<WindowInsetsAnimationCompat> runningAnimations) {
+    override fun onProgress(
+        insets: WindowInsetsCompat,
+        runningAnimations: List<WindowInsetsAnimationCompat>,
+    ): WindowInsetsCompat {
         if (animation == null) {
-            return insets;
+            return insets
         }
-        WindowInsetsAnimationCompat imeAnimation = null;
-        for (WindowInsetsAnimationCompat animation : runningAnimations) {
-            if ((animation.getTypeMask() & WindowInsetsCompat.Type.ime()) != 0) {
-                imeAnimation = animation;
-                break;
+        var imeAnimation: WindowInsetsAnimationCompat? = null
+        for (animation in runningAnimations) {
+            if (animation.typeMask and WindowInsetsCompat.Type.ime() != 0) {
+                imeAnimation = animation
+                break
             }
         }
         if (imeAnimation != null) {
-            for (View view : views) {
-                if (view == null) {
-                    continue;
-                }
-                int startPadding = startPaddings.containsKey(view) ? startPaddings.get(view) : 0;
-                int endPadding = endPaddings.containsKey(view) ? endPaddings.get(view) : 0;
-                view.setTranslationY(MathUtils.lerp(endPadding - startPadding, 0, animation.getInterpolatedFraction()));
+            for (view in views) {
+                val startPadding = if (startPaddings.containsKey(view)) startPaddings[view]!! else 0
+                val endPadding = if (endPaddings.containsKey(view)) endPaddings[view]!! else 0
+                view.translationY = MathUtils.lerp(
+                    (endPadding - startPadding).toFloat(),
+                    0f,
+                    animation!!.interpolatedFraction,
+                )
             }
         }
-        return insets;
+        return insets
     }
 
-    @Override
-    public void onEnd(@NonNull WindowInsetsAnimationCompat animation) {
-        super.onEnd(animation);
-        startPaddings.clear();
-        endPaddings.clear();
-        this.animation = null;
-        for (View view : views) {
-            if (view == null) {
-                continue;
-            }
-            view.setTranslationY(0);
+    override fun onEnd(animation: WindowInsetsAnimationCompat) {
+        super.onEnd(animation)
+        startPaddings.clear()
+        endPaddings.clear()
+        this.animation = null
+        for (view in views) {
+            view.translationY = 0f
         }
     }
 }