From 0ede0fa4059800c2b0295e648a9d2ff66550bea4 Mon Sep 17 00:00:00 2001
From: Tony Wickham <twickham@google.com>
Date: Wed, 29 Sep 2021 16:16:43 -0700
Subject: [PATCH] Aniamte stashed handle color changes

Test: Swipe from light background to dark background, ensure handle animates the color change
Bug: 193938970
Change-Id: I815c3a364019935bdf3d69309e695ac34b119c5e
---
 .../launcher3/taskbar/StashedHandleView.java  | 36 +++++++++++++++++--
 .../taskbar/StashedHandleViewController.java  |  5 +--
 2 files changed, 37 insertions(+), 4 deletions(-)

diff --git a/quickstep/src/com/android/launcher3/taskbar/StashedHandleView.java b/quickstep/src/com/android/launcher3/taskbar/StashedHandleView.java
index 0224bc4a5b..f7d4a30739 100644
--- a/quickstep/src/com/android/launcher3/taskbar/StashedHandleView.java
+++ b/quickstep/src/com/android/launcher3/taskbar/StashedHandleView.java
@@ -15,6 +15,10 @@
  */
 package com.android.launcher3.taskbar;
 
+import android.animation.Animator;
+import android.animation.AnimatorListenerAdapter;
+import android.animation.ObjectAnimator;
+import android.annotation.Nullable;
 import android.content.Context;
 import android.graphics.Rect;
 import android.util.AttributeSet;
@@ -23,15 +27,20 @@ import android.view.View;
 import androidx.annotation.ColorInt;
 import androidx.core.content.ContextCompat;
 
+import com.android.launcher3.LauncherAnimUtils;
 import com.android.launcher3.R;
 
 public class StashedHandleView extends View {
 
+    private static final long COLOR_CHANGE_DURATION = 120;
+
     private final @ColorInt int mStashedHandleLightColor;
     private final @ColorInt int mStashedHandleDarkColor;
     private final Rect mSampledRegion = new Rect();
     private final int[] mTmpArr = new int[2];
 
+    private @Nullable ObjectAnimator mColorChangeAnim;
+
     public StashedHandleView(Context context) {
         this(context, null);
     }
@@ -64,7 +73,30 @@ public class StashedHandleView extends View {
         return mSampledRegion;
     }
 
-    public void updateHandleColor(boolean isRegionDark) {
-        setBackgroundColor(isRegionDark ? mStashedHandleLightColor : mStashedHandleDarkColor);
+    /**
+     * Updates the handle color.
+     * @param isRegionDark Whether the background behind the handle is dark, and thus the handle
+     *                     should be light (and vice versa).
+     * @param animate Whether to animate the change, or apply it immediately.
+     */
+    public void updateHandleColor(boolean isRegionDark, boolean animate) {
+        int newColor = isRegionDark ? mStashedHandleLightColor : mStashedHandleDarkColor;
+        if (mColorChangeAnim != null) {
+            mColorChangeAnim.cancel();
+        }
+        if (animate) {
+            mColorChangeAnim = ObjectAnimator.ofArgb(this,
+                    LauncherAnimUtils.VIEW_BACKGROUND_COLOR, newColor);
+            mColorChangeAnim.addListener(new AnimatorListenerAdapter() {
+                @Override
+                public void onAnimationEnd(Animator animation) {
+                    mColorChangeAnim = null;
+                }
+            });
+            mColorChangeAnim.setDuration(COLOR_CHANGE_DURATION);
+            mColorChangeAnim.start();
+        } else {
+            setBackgroundColor(newColor);
+        }
     }
 }
diff --git a/quickstep/src/com/android/launcher3/taskbar/StashedHandleViewController.java b/quickstep/src/com/android/launcher3/taskbar/StashedHandleViewController.java
index 2858d7c38e..b9730a5114 100644
--- a/quickstep/src/com/android/launcher3/taskbar/StashedHandleViewController.java
+++ b/quickstep/src/com/android/launcher3/taskbar/StashedHandleViewController.java
@@ -70,7 +70,8 @@ public class StashedHandleViewController {
         mPrefs = Utilities.getPrefs(mActivity);
         mStashedHandleView = stashedHandleView;
         mStashedHandleView.updateHandleColor(
-                mPrefs.getBoolean(SHARED_PREFS_STASHED_HANDLE_REGION_DARK_KEY, false));
+                mPrefs.getBoolean(SHARED_PREFS_STASHED_HANDLE_REGION_DARK_KEY, false),
+                false /* animate */);
         final Resources resources = mActivity.getResources();
         mStashedHandleWidth = resources.getDimensionPixelSize(R.dimen.taskbar_stashed_handle_width);
         mStashedHandleHeight = resources.getDimensionPixelSize(
@@ -79,7 +80,7 @@ public class StashedHandleViewController {
                 new RegionSamplingHelper.SamplingCallback() {
                     @Override
                     public void onRegionDarknessChanged(boolean isRegionDark) {
-                        mStashedHandleView.updateHandleColor(isRegionDark);
+                        mStashedHandleView.updateHandleColor(isRegionDark, true /* animate */);
                         mPrefs.edit().putBoolean(SHARED_PREFS_STASHED_HANDLE_REGION_DARK_KEY,
                                 isRegionDark).apply();
                     }