commit 9e3aebd8dde8618a28c5d124887b69c32b9cde63
author Adam Cohen <adamcohen@google.com> Thu Jun 25 19:22:37 2020 -0700
committer Adam Cohen <adamcohen@google.com> Fri Jun 26 17:15:03 2020 +0000
tree 2cfa62e68501b6abea274fbc244d4372a5e72fe4
parent 6b79a3767dd7b64642269d288aae6d954a64d8b3

During accessible drag, hover events were not properly getting dispatched to the DragAndDropAccessibilityDelegate

=> regressed in ag/10634216 which attemped to use onHoverListener
=> the problem is that onHoverListener is only triggered when the event is passed to the CellLayout, however, as with all dispatching, these events are handled depth first, and so in cases where a child handled the event, it would never bubble back up to the parent.
=> instead we have to continue to override dispatchHover event to always give presecedence to the delegate when it exists

Bug: 155956518

Change-Id: Ic3ecf1b422c1821456328035a66a2fc1277e6746
(cherry picked from commit 6e7c37a2053c4334499c65b8a17dc0e85df5a54a)

src/com/android/launcher3/CellLayout.java

diff --git a/src/com/android/launcher3/CellLayout.java b/src/com/android/launcher3/CellLayout.java
index ed71ddc..89d768c 100644
--- a/src/com/android/launcher3/CellLayout.java
+++ b/src/com/android/launcher3/CellLayout.java
@@ -182,7 +182,7 @@
     private static final Paint sPaint = new Paint();
 
     // Related to accessible drag and drop
-    private boolean mUseTouchHelper = false;
+    DragAndDropAccessibilityDelegate mTouchHelper;
 
     public CellLayout(Context context) {
         this(context, null);
@@ -290,17 +290,15 @@
         addView(mShortcutsAndWidgets);
     }
 
-
     /**
      * Sets or clears a delegate used for accessible drag and drop
      */
     public void setDragAndDropAccessibilityDelegate(DragAndDropAccessibilityDelegate delegate) {
         setOnClickListener(delegate);
-        setOnHoverListener(delegate);
         ViewCompat.setAccessibilityDelegate(this, delegate);
 
-        mUseTouchHelper = delegate != null;
-        int accessibilityFlag = mUseTouchHelper
+        mTouchHelper = delegate;
+        int accessibilityFlag = mTouchHelper != null
                 ? IMPORTANT_FOR_ACCESSIBILITY_YES : IMPORTANT_FOR_ACCESSIBILITY_NO;
         setImportantForAccessibility(accessibilityFlag);
         getShortcutsAndWidgets().setImportantForAccessibility(accessibilityFlag);
@@ -313,9 +311,18 @@
     }
 
     @Override
+    public boolean dispatchHoverEvent(MotionEvent event) {
+        // Always attempt to dispatch hover events to accessibility first.
+        if (mTouchHelper != null && mTouchHelper.dispatchHoverEvent(event)) {
+            return true;
+        }
+        return super.dispatchHoverEvent(event);
+    }
+
+    @Override
     public boolean onInterceptTouchEvent(MotionEvent ev) {
-        if (mUseTouchHelper ||
-                (mInterceptTouchListener != null && mInterceptTouchListener.onTouch(this, ev))) {
+        if (mTouchHelper != null
+                || (mInterceptTouchListener != null && mInterceptTouchListener.onTouch(this, ev))) {
             return true;
         }
         return false;