Avoid sending incorrect or redundant hover events.

Make sure ACTION_HOVER_EXIT is never sent to a
ViewGroup more than once.

While processing ACTION_HOVER_MOVE during exiting
a hover target never send it a ACTION_HOVER_ENTER.

Test: android.view.cts.HoverTest
Bug: 32071138
Bug: 32071098
Change-Id: Ibc1809137907176437a3a5a4ea14b00f1c629b58

1 files changed, 22 insertions, 0 deletions

diff --git a/core/java/android/view/MotionEvent.java b/core/java/android/view/MotionEvent.java
index 3e8d5777bfa6..2316b3829f37 100644
--- a/core/java/android/view/MotionEvent.java
+++ b/core/java/android/view/MotionEvent.java
@@ -436,6 +436,14 @@ public final class MotionEvent extends InputEvent implements Parcelable {
     public static final int FLAG_WINDOW_IS_PARTIALLY_OBSCURED = 0x2;
 
     /**
+     * This private flag is only set on {@link #ACTION_HOVER_MOVE} events and indicates that
+     * this event will be immediately followed by a {@link #ACTION_HOVER_EXIT}. It is used to
+     * prevent generating redundant {@link #ACTION_HOVER_ENTER} events.
+     * @hide
+     */
+    public static final int FLAG_HOVER_EXIT_PENDING = 0x4;
+
+    /**
      * Private flag that indicates when the system has detected that this motion event
      * may be inconsistent with respect to the sequence of previously delivered motion events,
      * such as when a pointer move event is sent but the pointer is not down.
@@ -1947,6 +1955,20 @@ public final class MotionEvent extends InputEvent implements Parcelable {
                 : flags & ~FLAG_TARGET_ACCESSIBILITY_FOCUS);
     }
 
+    /** @hide */
+    public final boolean isHoverExitPending() {
+        final int flags = getFlags();
+        return (flags & FLAG_HOVER_EXIT_PENDING) != 0;
+    }
+
+    /** @hide */
+    public void setHoverExitPending(boolean hoverExitPending) {
+        final int flags = getFlags();
+        nativeSetFlags(mNativePtr, hoverExitPending
+                ? flags | FLAG_HOVER_EXIT_PENDING
+                : flags & ~FLAG_HOVER_EXIT_PENDING);
+    }
+
     /**
      * Returns the time (in ms) when the user originally pressed down to start
      * a stream of position events.