From d08e03388faba87c1834b2efb234ba5070a55457 Mon Sep 17 00:00:00 2001
From: Pat Manning <patmanning@google.com>
Date: Tue, 12 Apr 2022 11:12:57 +0000
Subject: [PATCH] Re-land "Animate overivew actions view hiding on scroll."

Reverts commit f5f14acba3b0627f72237095c64798e9cbbb8608

Bug: 228137694
Bug: 221113300
Change-Id: I683092796f5de0476e09692897d80a3655ae6925
---
 .../quickstep/views/OverviewActionsView.java  |  4 +-
 .../android/quickstep/views/RecentsView.java  | 48 +++++++++++++------
 2 files changed, 34 insertions(+), 18 deletions(-)

diff --git a/quickstep/src/com/android/quickstep/views/OverviewActionsView.java b/quickstep/src/com/android/quickstep/views/OverviewActionsView.java
index 49a540f0d1..1c4e497332 100644
--- a/quickstep/src/com/android/quickstep/views/OverviewActionsView.java
+++ b/quickstep/src/com/android/quickstep/views/OverviewActionsView.java
@@ -56,7 +56,6 @@ public class OverviewActionsView<T extends OverlayUICallbacks> extends FrameLayo
             HIDDEN_NON_ZERO_ROTATION,
             HIDDEN_NO_TASKS,
             HIDDEN_NO_RECENTS,
-            HIDDEN_FOCUSED_SCROLL,
             HIDDEN_SPLIT_SCREEN})
     @Retention(RetentionPolicy.SOURCE)
     public @interface ActionsHiddenFlags { }
@@ -64,8 +63,7 @@ public class OverviewActionsView<T extends OverlayUICallbacks> extends FrameLayo
     public static final int HIDDEN_NON_ZERO_ROTATION = 1 << 0;
     public static final int HIDDEN_NO_TASKS = 1 << 1;
     public static final int HIDDEN_NO_RECENTS = 1 << 2;
-    public static final int HIDDEN_FOCUSED_SCROLL = 1 << 3;
-    public static final int HIDDEN_SPLIT_SCREEN = 1 << 4;
+    public static final int HIDDEN_SPLIT_SCREEN = 1 << 3;
 
     @IntDef(flag = true, value = {
             DISABLED_SCROLLING,
diff --git a/quickstep/src/com/android/quickstep/views/RecentsView.java b/quickstep/src/com/android/quickstep/views/RecentsView.java
index 5d71ebd481..71b2cea444 100644
--- a/quickstep/src/com/android/quickstep/views/RecentsView.java
+++ b/quickstep/src/com/android/quickstep/views/RecentsView.java
@@ -378,6 +378,8 @@ public abstract class RecentsView<ACTIVITY_TYPE extends StatefulActivity<STATE_T
     // OverScroll constants
     private static final int OVERSCROLL_PAGE_SNAP_ANIMATION_DURATION = 270;
 
+    private static final int DEFAULT_ACTIONS_VIEW_ALPHA_ANIMATION_DURATION = 300;
+
     private static final int DISMISS_TASK_DURATION = 300;
     private static final int ADDITION_TASK_DURATION = 200;
     private static final float INITIAL_DISMISS_TRANSLATION_INTERPOLATION_OFFSET = 0.55f;
@@ -652,6 +654,8 @@ public abstract class RecentsView<ACTIVITY_TYPE extends StatefulActivity<STATE_T
     private TaskView mMovingTaskView;
 
     private OverviewActionsView mActionsView;
+    private ObjectAnimator mActionsViewAlphaAnimator;
+    private float mActionsViewAlphaAnimatorFinalValue;
 
     private MultiWindowModeChangedListener mMultiWindowModeChangedListener =
             new MultiWindowModeChangedListener() {
@@ -1145,6 +1149,11 @@ public abstract class RecentsView<ACTIVITY_TYPE extends StatefulActivity<STATE_T
         return getScrollForPage(taskIndex) == getPagedOrientationHandler().getPrimaryScroll(this);
     }
 
+    private boolean isFocusedTaskInExpectedScrollPosition() {
+        TaskView focusedTask = getFocusedTaskView();
+        return focusedTask != null && isTaskInExpectedScrollPosition(indexOfChild(focusedTask));
+    }
+
     /**
      * Returns a {@link TaskView} that has taskId matching {@code taskId} or null if no match.
      */
@@ -1191,13 +1200,15 @@ public abstract class RecentsView<ACTIVITY_TYPE extends StatefulActivity<STATE_T
     @Override
     protected void onPageBeginTransition() {
         super.onPageBeginTransition();
-        mActionsView.updateDisabledFlags(OverviewActionsView.DISABLED_SCROLLING, true);
+        if (!mActivity.getDeviceProfile().isTablet) {
+            mActionsView.updateDisabledFlags(OverviewActionsView.DISABLED_SCROLLING, true);
+        }
     }
 
     @Override
     protected void onPageEndTransition() {
         super.onPageEndTransition();
-        if (isClearAllHidden()) {
+        if (isClearAllHidden() && !mActivity.getDeviceProfile().isTablet) {
             mActionsView.updateDisabledFlags(OverviewActionsView.DISABLED_SCROLLING, false);
         }
         if (getNextPage() > 0) {
@@ -1808,16 +1819,24 @@ public abstract class RecentsView<ACTIVITY_TYPE extends StatefulActivity<STATE_T
     }
 
     private void updateActionsViewFocusedScroll() {
-        boolean hiddenFocusedScroll;
         if (showAsGrid()) {
-            TaskView focusedTaskView = getFocusedTaskView();
-            hiddenFocusedScroll = focusedTaskView == null
-                    || !isTaskInExpectedScrollPosition(indexOfChild(focusedTaskView));
-        } else {
-            hiddenFocusedScroll = false;
+            float actionsViewAlphaValue = isFocusedTaskInExpectedScrollPosition() ? 1 : 0;
+            // If animation is already in progress towards the same end value, do not restart.
+            if (mActionsViewAlphaAnimator == null || !mActionsViewAlphaAnimator.isStarted()
+                    || (mActionsViewAlphaAnimator.isStarted()
+                    && mActionsViewAlphaAnimatorFinalValue != actionsViewAlphaValue)) {
+                animateActionsViewAlpha(actionsViewAlphaValue,
+                        DEFAULT_ACTIONS_VIEW_ALPHA_ANIMATION_DURATION);
+            }
         }
-        mActionsView.updateHiddenFlags(OverviewActionsView.HIDDEN_FOCUSED_SCROLL,
-                hiddenFocusedScroll);
+    }
+
+    private void animateActionsViewAlpha(float alphaValue, long duration) {
+        mActionsViewAlphaAnimator = ObjectAnimator.ofFloat(
+                mActionsView.getVisibilityAlpha(), MultiValueAlpha.VALUE, alphaValue);
+        mActionsViewAlphaAnimatorFinalValue = alphaValue;
+        mActionsViewAlphaAnimator.setDuration(duration);
+        mActionsViewAlphaAnimator.start();
     }
 
     /**
@@ -2346,10 +2365,9 @@ public abstract class RecentsView<ACTIVITY_TYPE extends StatefulActivity<STATE_T
     }
 
     private void animateActionsViewIn() {
-        ObjectAnimator anim = ObjectAnimator.ofFloat(
-                mActionsView.getVisibilityAlpha(), MultiValueAlpha.VALUE, 0, 1);
-        anim.setDuration(TaskView.SCALE_ICON_DURATION);
-        anim.start();
+        if (!showAsGrid() || isFocusedTaskInExpectedScrollPosition()) {
+            animateActionsViewAlpha(1, TaskView.SCALE_ICON_DURATION);
+        }
     }
 
     public void animateUpTaskIconScale() {
@@ -3292,7 +3310,7 @@ public abstract class RecentsView<ACTIVITY_TYPE extends StatefulActivity<STATE_T
                         // Update various scroll-dependent UI.
                         dispatchScrollChanged();
                         updateActionsViewFocusedScroll();
-                        if (isClearAllHidden()) {
+                        if (isClearAllHidden() && !mActivity.getDeviceProfile().isTablet) {
                             mActionsView.updateDisabledFlags(OverviewActionsView.DISABLED_SCROLLING,
                                     false);
                         }