Convert ClearAllButton to Kotlin

Bug: 389209338
Flag: EXEMPT refactor
Test: m
Change-Id: Iaafe69ae14744e418d3c30d4d9fc6f417f36f230
diff --git a/quickstep/src/com/android/quickstep/views/ClearAllButton.java b/quickstep/src/com/android/quickstep/views/ClearAllButton.java
deleted file mode 100644
index 2426697..0000000
--- a/quickstep/src/com/android/quickstep/views/ClearAllButton.java
+++ /dev/null
@@ -1,333 +0,0 @@
-/*
- * Copyright (C) 2018 The Android Open Source Project
- *
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * You may obtain a copy of the License at
- *
- *      http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
- */
-
-package com.android.quickstep.views;
-
-import static com.android.quickstep.util.BorderAnimator.DEFAULT_BORDER_COLOR;
-
-import android.content.Context;
-import android.content.res.Resources;
-import android.content.res.TypedArray;
-import android.graphics.Canvas;
-import android.graphics.Rect;
-import android.util.AttributeSet;
-import android.util.FloatProperty;
-import android.widget.Button;
-
-import androidx.annotation.NonNull;
-import androidx.annotation.Nullable;
-
-import com.android.launcher3.Flags;
-import com.android.launcher3.R;
-import com.android.quickstep.orientation.RecentsPagedOrientationHandler;
-import com.android.quickstep.util.BorderAnimator;
-
-import kotlin.Unit;
-
-public class ClearAllButton extends Button {
-
-    public static final FloatProperty<ClearAllButton> VISIBILITY_ALPHA =
-            new FloatProperty<ClearAllButton>("visibilityAlpha") {
-                @Override
-                public Float get(ClearAllButton view) {
-                    return view.mVisibilityAlpha;
-                }
-
-                @Override
-                public void setValue(ClearAllButton view, float v) {
-                    view.setVisibilityAlpha(v);
-                }
-            };
-
-    public static final FloatProperty<ClearAllButton> DISMISS_ALPHA =
-            new FloatProperty<ClearAllButton>("dismissAlpha") {
-                @Override
-                public Float get(ClearAllButton view) {
-                    return view.mDismissAlpha;
-                }
-
-                @Override
-                public void setValue(ClearAllButton view, float v) {
-                    view.setDismissAlpha(v);
-                }
-            };
-
-    private float mScrollAlpha = 1;
-    private float mContentAlpha = 1;
-    private float mVisibilityAlpha = 1;
-    private float mDismissAlpha = 1;
-    private float mFullscreenProgress = 1;
-    private float mGridProgress = 1;
-
-    private boolean mIsRtl;
-    private float mNormalTranslationPrimary;
-    private float mFullscreenTranslationPrimary;
-    private float mGridTranslationPrimary;
-    private float mTaskAlignmentTranslationY;
-    private float mGridScrollOffset;
-    private float mScrollOffsetPrimary;
-
-    private int mSidePadding;
-    private int mOutlinePadding;
-    private boolean mBorderEnabled;
-    @Nullable
-    private final BorderAnimator mFocusBorderAnimator;
-
-    public ClearAllButton(Context context, AttributeSet attrs) {
-        super(context, attrs);
-        mIsRtl = getLayoutDirection() == LAYOUT_DIRECTION_RTL;
-
-        if (Flags.enableFocusOutline()) {
-            TypedArray styledAttrs = context.obtainStyledAttributes(attrs,
-                    R.styleable.ClearAllButton);
-            Resources resources = getResources();
-            mOutlinePadding = resources.getDimensionPixelSize(
-                    R.dimen.recents_clear_all_outline_padding);
-            mFocusBorderAnimator =
-                    BorderAnimator.createSimpleBorderAnimator(
-                            /* borderRadiusPx= */ resources.getDimensionPixelSize(
-                                    R.dimen.recents_clear_all_outline_radius),
-                            /* borderWidthPx= */ context.getResources().getDimensionPixelSize(
-                                    R.dimen.keyboard_quick_switch_border_width),
-                            /* boundsBuilder= */ this::updateBorderBounds,
-                            /* targetView= */ this,
-                            /* borderColor= */ styledAttrs.getColor(
-                                    R.styleable.ClearAllButton_focusBorderColor,
-                                    DEFAULT_BORDER_COLOR));
-            styledAttrs.recycle();
-        } else {
-            mFocusBorderAnimator = null;
-        }
-    }
-
-    private Unit updateBorderBounds(@NonNull Rect bounds) {
-        bounds.set(0, 0, getWidth(), getHeight());
-        // Make the value negative to form a padding between button and outline
-        bounds.inset(-mOutlinePadding, -mOutlinePadding);
-        return Unit.INSTANCE;
-    }
-
-    @Override
-    public void onFocusChanged(boolean gainFocus, int direction, Rect previouslyFocusedRect) {
-        super.onFocusChanged(gainFocus, direction, previouslyFocusedRect);
-        if (mFocusBorderAnimator != null && mBorderEnabled) {
-            mFocusBorderAnimator.setBorderVisibility(gainFocus, /* animated= */ true);
-        }
-    }
-
-    /**
-     * Enable or disable showing border on focus change
-     */
-    public void setBorderEnabled(boolean enabled) {
-        if (mBorderEnabled == enabled) {
-            return;
-        }
-
-        mBorderEnabled = enabled;
-        if (mFocusBorderAnimator != null) {
-            mFocusBorderAnimator.setBorderVisibility(/* visible= */
-                    enabled && isFocused(), /* animated= */true);
-        }
-    }
-
-    @Override
-    public void draw(Canvas canvas) {
-        if (mFocusBorderAnimator != null) {
-            mFocusBorderAnimator.drawBorder(canvas);
-        }
-        super.draw(canvas);
-    }
-
-    @Override
-    protected void onLayout(boolean changed, int left, int top, int right, int bottom) {
-        super.onLayout(changed, left, top, right, bottom);
-        RecentsPagedOrientationHandler orientationHandler =
-                getRecentsView().getPagedOrientationHandler();
-        mSidePadding = orientationHandler.getClearAllSidePadding(getRecentsView(), mIsRtl);
-    }
-
-    private RecentsView getRecentsView() {
-        return (RecentsView) getParent();
-    }
-
-    @Override
-    public void onRtlPropertiesChanged(int layoutDirection) {
-        super.onRtlPropertiesChanged(layoutDirection);
-        mIsRtl = getLayoutDirection() == LAYOUT_DIRECTION_RTL;
-    }
-
-    @Override
-    public boolean hasOverlappingRendering() {
-        return false;
-    }
-
-    public float getScrollAlpha() {
-        return mScrollAlpha;
-    }
-
-    public void setContentAlpha(float alpha) {
-        if (mContentAlpha != alpha) {
-            mContentAlpha = alpha;
-            updateAlpha();
-        }
-    }
-
-    public void setVisibilityAlpha(float alpha) {
-        if (mVisibilityAlpha != alpha) {
-            mVisibilityAlpha = alpha;
-            updateAlpha();
-        }
-    }
-
-    public void setDismissAlpha(float alpha) {
-        if (mDismissAlpha != alpha) {
-            mDismissAlpha = alpha;
-            updateAlpha();
-        }
-    }
-
-    public void onRecentsViewScroll(int scroll, boolean gridEnabled) {
-        RecentsView recentsView = getRecentsView();
-        if (recentsView == null) {
-            return;
-        }
-
-        RecentsPagedOrientationHandler orientationHandler =
-                recentsView.getPagedOrientationHandler();
-        float orientationSize = orientationHandler.getPrimaryValue(getWidth(), getHeight());
-        if (orientationSize == 0) {
-            return;
-        }
-
-        int clearAllScroll = recentsView.getClearAllScroll();
-        int adjustedScrollFromEdge = Math.abs(scroll - clearAllScroll);
-        float shift = Math.min(adjustedScrollFromEdge, orientationSize);
-        mNormalTranslationPrimary = mIsRtl ? -shift : shift;
-        if (!gridEnabled) {
-            mNormalTranslationPrimary += mSidePadding;
-        }
-        applyPrimaryTranslation();
-        applySecondaryTranslation();
-        float clearAllSpacing =
-                recentsView.getPageSpacing() + recentsView.getClearAllExtraPageSpacing();
-        clearAllSpacing = mIsRtl ? -clearAllSpacing : clearAllSpacing;
-        mScrollAlpha = Math.max((clearAllScroll + clearAllSpacing - scroll) / clearAllSpacing, 0);
-        updateAlpha();
-    }
-
-    private void updateAlpha() {
-        final float alpha = mScrollAlpha * mContentAlpha * mVisibilityAlpha * mDismissAlpha;
-        setAlpha(alpha);
-        setClickable(Math.min(alpha, 1) == 1);
-    }
-
-    public void setFullscreenTranslationPrimary(float fullscreenTranslationPrimary) {
-        mFullscreenTranslationPrimary = fullscreenTranslationPrimary;
-        applyPrimaryTranslation();
-    }
-
-    /**
-     * Sets `mTaskAlignmentTranslationY` to the given `value`. In order to put the button at the
-     * middle in the secondary coordinate.
-     */
-    public void setTaskAlignmentTranslationY(float value) {
-        mTaskAlignmentTranslationY = value;
-        applySecondaryTranslation();
-    }
-
-    public void setGridTranslationPrimary(float gridTranslationPrimary) {
-        mGridTranslationPrimary = gridTranslationPrimary;
-        applyPrimaryTranslation();
-    }
-
-    public void setGridScrollOffset(float gridScrollOffset) {
-        mGridScrollOffset = gridScrollOffset;
-    }
-
-    public void setScrollOffsetPrimary(float scrollOffsetPrimary) {
-        mScrollOffsetPrimary = scrollOffsetPrimary;
-    }
-
-    public float getScrollAdjustment(boolean fullscreenEnabled, boolean gridEnabled) {
-        float scrollAdjustment = 0;
-        if (fullscreenEnabled) {
-            scrollAdjustment += mFullscreenTranslationPrimary;
-        }
-        if (gridEnabled) {
-            scrollAdjustment += mGridTranslationPrimary + mGridScrollOffset;
-        }
-        scrollAdjustment += mScrollOffsetPrimary;
-        return scrollAdjustment;
-    }
-
-    public float getOffsetAdjustment(boolean fullscreenEnabled, boolean gridEnabled) {
-        return getScrollAdjustment(fullscreenEnabled, gridEnabled);
-    }
-
-    /**
-     * Adjust translation when this TaskView is about to be shown fullscreen.
-     *
-     * @param progress: 0 = no translation; 1 = translate according to TaskVIew translations.
-     */
-    public void setFullscreenProgress(float progress) {
-        mFullscreenProgress = progress;
-        applyPrimaryTranslation();
-    }
-
-    /**
-     * Moves ClearAllButton between carousel and 2 row grid.
-     *
-     * @param gridProgress 0 = carousel; 1 = 2 row grid.
-     */
-    public void setGridProgress(float gridProgress) {
-        mGridProgress = gridProgress;
-        applyPrimaryTranslation();
-    }
-
-    private void applyPrimaryTranslation() {
-        RecentsView recentsView = getRecentsView();
-        if (recentsView == null) {
-            return;
-        }
-
-        RecentsPagedOrientationHandler orientationHandler =
-                recentsView.getPagedOrientationHandler();
-        orientationHandler.getPrimaryViewTranslate().set(this,
-                orientationHandler.getPrimaryValue(0f, mTaskAlignmentTranslationY)
-                        + mNormalTranslationPrimary + getFullscreenTrans(
-                        mFullscreenTranslationPrimary) + getGridTrans(mGridTranslationPrimary));
-    }
-
-    private void applySecondaryTranslation() {
-        RecentsView recentsView = getRecentsView();
-        if (recentsView == null) {
-            return;
-        }
-
-        RecentsPagedOrientationHandler orientationHandler =
-                recentsView.getPagedOrientationHandler();
-        orientationHandler.getSecondaryViewTranslate().set(this,
-                orientationHandler.getSecondaryValue(0f, mTaskAlignmentTranslationY));
-    }
-
-    private float getFullscreenTrans(float endTranslation) {
-        return mFullscreenProgress > 0 ? endTranslation : 0;
-    }
-
-    private float getGridTrans(float endTranslation) {
-        return mGridProgress > 0 ? endTranslation : 0;
-    }
-}
diff --git a/quickstep/src/com/android/quickstep/views/ClearAllButton.kt b/quickstep/src/com/android/quickstep/views/ClearAllButton.kt
new file mode 100644
index 0000000..ef62597
--- /dev/null
+++ b/quickstep/src/com/android/quickstep/views/ClearAllButton.kt
@@ -0,0 +1,269 @@
+/*
+ * Copyright (C) 2025 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package com.android.quickstep.views
+
+import android.content.Context
+import android.graphics.Canvas
+import android.graphics.Rect
+import android.util.AttributeSet
+import android.util.FloatProperty
+import android.widget.Button
+import com.android.launcher3.Flags.enableFocusOutline
+import com.android.launcher3.R
+import com.android.quickstep.util.BorderAnimator
+import com.android.quickstep.util.BorderAnimator.Companion.createSimpleBorderAnimator
+import kotlin.math.abs
+import kotlin.math.min
+
+class ClearAllButton @JvmOverloads constructor(context: Context, attrs: AttributeSet? = null) :
+    Button(context, attrs) {
+
+    var scrollAlpha = 1f
+        set(value) {
+            field = value
+            updateAlpha()
+        }
+
+    var contentAlpha = 1f
+        set(value) {
+            field = value
+            updateAlpha()
+        }
+
+    var visibilityAlpha = 1f
+        set(value) {
+            field = value
+            updateAlpha()
+        }
+
+    var dismissAlpha = 1f
+        set(value) {
+            field = value
+            updateAlpha()
+        }
+
+    var fullscreenProgress = 1f
+        set(value) {
+            if (field == value) {
+                return
+            }
+            field = value
+            applyPrimaryTranslation()
+        }
+
+    /**
+     * Moves ClearAllButton between carousel and 2 row grid.
+     *
+     * 0 = carousel; 1 = 2 row grid.
+     */
+    var gridProgress = 1f
+        set(value) {
+            if (field == value) {
+                return
+            }
+            field = value
+            applyPrimaryTranslation()
+        }
+
+    private var normalTranslationPrimary = 0f
+    var fullscreenTranslationPrimary = 0f
+        set(value) {
+            if (field == value) {
+                return
+            }
+            field = value
+            applyPrimaryTranslation()
+        }
+
+    var gridTranslationPrimary = 0f
+        set(value) {
+            if (field == value) {
+                return
+            }
+            field = value
+            applyPrimaryTranslation()
+        }
+
+    /** Used to put the button at the middle in the secondary coordinate. */
+    var taskAlignmentTranslationY = 0f
+        set(value) {
+            if (field == value) {
+                return
+            }
+            field = value
+            applySecondaryTranslation()
+        }
+
+    var gridScrollOffset = 0f
+    var scrollOffsetPrimary = 0f
+
+    private var sidePadding = 0
+    var borderEnabled = false
+        set(value) {
+            if (field == value) {
+                return
+            }
+            field = value
+            focusBorderAnimator?.setBorderVisibility(visible = field && isFocused, animated = true)
+        }
+
+    private val focusBorderAnimator: BorderAnimator? =
+        if (enableFocusOutline())
+            createSimpleBorderAnimator(
+                context.resources.getDimensionPixelSize(R.dimen.recents_clear_all_outline_radius),
+                context.resources.getDimensionPixelSize(R.dimen.keyboard_quick_switch_border_width),
+                this::getBorderBounds,
+                this,
+                context
+                    .obtainStyledAttributes(attrs, R.styleable.ClearAllButton)
+                    .getColor(
+                        R.styleable.ClearAllButton_focusBorderColor,
+                        BorderAnimator.DEFAULT_BORDER_COLOR,
+                    ),
+            )
+        else null
+
+    private fun getBorderBounds(bounds: Rect) {
+        bounds.set(0, 0, width, height)
+        val outlinePadding =
+            context.resources.getDimensionPixelSize(R.dimen.recents_clear_all_outline_padding)
+        // Make the value negative to form a padding between button and outline
+        bounds.inset(-outlinePadding, -outlinePadding)
+    }
+
+    public override fun onFocusChanged(
+        gainFocus: Boolean,
+        direction: Int,
+        previouslyFocusedRect: Rect?,
+    ) {
+        super.onFocusChanged(gainFocus, direction, previouslyFocusedRect)
+        if (borderEnabled) {
+            focusBorderAnimator?.setBorderVisibility(gainFocus, /* animated= */ true)
+        }
+    }
+
+    override fun draw(canvas: Canvas) {
+        focusBorderAnimator?.drawBorder(canvas)
+        super.draw(canvas)
+    }
+
+    override fun onLayout(changed: Boolean, left: Int, top: Int, right: Int, bottom: Int) {
+        super.onLayout(changed, left, top, right, bottom)
+        sidePadding =
+            recentsView?.let { it.pagedOrientationHandler?.getClearAllSidePadding(it, isLayoutRtl) }
+                ?: 0
+    }
+
+    private val recentsView: RecentsView<*, *>?
+        get() = parent as? RecentsView<*, *>?
+
+    override fun hasOverlappingRendering() = false
+
+    fun onRecentsViewScroll(scroll: Int, gridEnabled: Boolean) {
+        val recentsView = recentsView ?: return
+
+        val orientationSize =
+            recentsView.pagedOrientationHandler.getPrimaryValue(width, height).toFloat()
+        if (orientationSize == 0f) {
+            return
+        }
+
+        val clearAllScroll = recentsView.clearAllScroll
+        val adjustedScrollFromEdge = abs((scroll - clearAllScroll)).toFloat()
+        val shift = min(adjustedScrollFromEdge, orientationSize)
+        normalTranslationPrimary = if (isLayoutRtl) -shift else shift
+        if (!gridEnabled) {
+            normalTranslationPrimary += sidePadding.toFloat()
+        }
+        applyPrimaryTranslation()
+        applySecondaryTranslation()
+        var clearAllSpacing = recentsView.pageSpacing + recentsView.clearAllExtraPageSpacing
+        clearAllSpacing = if (isLayoutRtl) -clearAllSpacing else clearAllSpacing
+        scrollAlpha =
+            ((clearAllScroll + clearAllSpacing - scroll) / clearAllSpacing.toFloat()).coerceAtLeast(
+                0f
+            )
+    }
+
+    private fun updateAlpha() {
+        val alpha = scrollAlpha * contentAlpha * visibilityAlpha * dismissAlpha
+        this.alpha = alpha
+        isClickable = alpha >= 1f
+    }
+
+    fun getScrollAdjustment(fullscreenEnabled: Boolean, gridEnabled: Boolean): Float {
+        var scrollAdjustment = 0f
+        if (fullscreenEnabled) {
+            scrollAdjustment += fullscreenTranslationPrimary
+        }
+        if (gridEnabled) {
+            scrollAdjustment += gridTranslationPrimary + gridScrollOffset
+        }
+        scrollAdjustment += scrollOffsetPrimary
+        return scrollAdjustment
+    }
+
+    fun getOffsetAdjustment(fullscreenEnabled: Boolean, gridEnabled: Boolean) =
+        getScrollAdjustment(fullscreenEnabled, gridEnabled)
+
+    private fun applyPrimaryTranslation() {
+        val recentsView = recentsView ?: return
+        val orientationHandler = recentsView.pagedOrientationHandler
+        orientationHandler.primaryViewTranslate.set(
+            this,
+            (orientationHandler.getPrimaryValue(0f, taskAlignmentTranslationY) +
+                normalTranslationPrimary +
+                getFullscreenTrans(fullscreenTranslationPrimary) +
+                getGridTrans(gridTranslationPrimary)),
+        )
+    }
+
+    private fun applySecondaryTranslation() {
+        val recentsView = recentsView ?: return
+        val orientationHandler = recentsView.pagedOrientationHandler
+        orientationHandler.secondaryViewTranslate.set(
+            this,
+            orientationHandler.getSecondaryValue(0f, taskAlignmentTranslationY),
+        )
+    }
+
+    private fun getFullscreenTrans(endTranslation: Float) =
+        if (fullscreenProgress > 0) endTranslation else 0f
+
+    private fun getGridTrans(endTranslation: Float) = if (gridProgress > 0) endTranslation else 0f
+
+    companion object {
+        @JvmField
+        val VISIBILITY_ALPHA: FloatProperty<ClearAllButton> =
+            object : FloatProperty<ClearAllButton>("visibilityAlpha") {
+                override fun setValue(clearAllButton: ClearAllButton, value: Float) {
+                    clearAllButton.visibilityAlpha = value
+                }
+
+                override fun get(clearAllButton: ClearAllButton) = clearAllButton.visibilityAlpha
+            }
+
+        @JvmField
+        val DISMISS_ALPHA: FloatProperty<ClearAllButton> =
+            object : FloatProperty<ClearAllButton>("dismissAlpha") {
+                override fun setValue(clearAllButton: ClearAllButton, value: Float) {
+                    clearAllButton.dismissAlpha = value
+                }
+
+                override fun get(clearAllButton: ClearAllButton) = clearAllButton.dismissAlpha
+            }
+    }
+}