commit 29fbab4ddd664a7c36fb58940fd457c67b3bfe52
author Pat Manning <patmanning@google.com> Mon Apr 04 16:08:52 2022 +0100
committer Pat Manning <patmanning@google.com> Tue Apr 12 15:32:06 2022 +0100
tree b5d0b5e4c8e22cd768ed045fb32b483549ec6690
parent 4349d21246670c3834ae763850d86a5a00bcdb61

Animate clear all button's alpha after last task has scrolled beyond its edge.

Test: manual
Fix: 208879377
Change-Id: Iad43abbe36d11317869a0c5aa6a8d59fd1fddb67

quickstep/src/com/android/quickstep/views/ClearAllButton.java

diff --git a/quickstep/src/com/android/quickstep/views/ClearAllButton.java b/quickstep/src/com/android/quickstep/views/ClearAllButton.java
index 332cbeb..50be5ea 100644
--- a/quickstep/src/com/android/quickstep/views/ClearAllButton.java
+++ b/quickstep/src/com/android/quickstep/views/ClearAllButton.java
@@ -141,7 +141,10 @@
         }
         applyPrimaryTranslation();
         applySecondaryTranslation();
-        mScrollAlpha = 1 - shift / orientationSize;
+        float clearAllSpacing =
+                recentsView.getPageSpacing() + recentsView.getClearAllExtraPageSpacing();
+        clearAllSpacing = mIsRtl ? -clearAllSpacing : clearAllSpacing;
+        mScrollAlpha = Math.max((clearAllScroll + clearAllSpacing - scroll) / clearAllSpacing, 0);
         updateAlpha();
     }
 

quickstep/src/com/android/quickstep/views/RecentsView.java

diff --git a/quickstep/src/com/android/quickstep/views/RecentsView.java b/quickstep/src/com/android/quickstep/views/RecentsView.java
index e64e439..3fa0169 100644
--- a/quickstep/src/com/android/quickstep/views/RecentsView.java
+++ b/quickstep/src/com/android/quickstep/views/RecentsView.java
@@ -1289,10 +1289,11 @@
                     return;
                 }
                 TaskView taskView = getTaskViewAt(mNextPage);
-                // Only snap to fully visible focused task.
-                if (taskView == null
-                        || !taskView.isFocusedTask()
-                        || !isTaskViewFullyVisible(taskView)) {
+                // Snap to fully visible focused task and clear all button.
+                boolean shouldSnapToFocusedTask = taskView != null && taskView.isFocusedTask()
+                        && isTaskViewFullyVisible(taskView);
+                boolean shouldSnapToClearAll = mNextPage == indexOfChild(mClearAllButton);
+                if (!shouldSnapToFocusedTask && !shouldSnapToClearAll) {
                     return;
                 }
             }
@@ -4535,7 +4536,7 @@
                 ? getClearAllExtraPageSpacing() : 0;
     }
 
-    private int getClearAllExtraPageSpacing() {
+    protected int getClearAllExtraPageSpacing() {
         return showAsGrid()
                 ? Math.max(mActivity.getDeviceProfile().overviewGridSideMargin - mPageSpacing, 0)
                 : 0;