Add View#cancelPendingInputEvents API

This API allows an application to cancel deferred high-level input
events already in flight. It forms one tool of several to help apps
debounce input events and prevent things like multiple startActivity
calls, FragmentTransactions, etc. from executing when only one was
desired since it's otherwise not desirable for things like click
events to fire synchronously.

Change-Id: I60b12cd5350898065f0019d616e24d779eb8cff9

1 files changed, 11 insertions, 0 deletions

diff --git a/core/java/android/view/ViewGroup.java b/core/java/android/view/ViewGroup.java
index 2d75b063ca74..faeee3fa5ce7 100644
--- a/core/java/android/view/ViewGroup.java
+++ b/core/java/android/view/ViewGroup.java
@@ -3182,6 +3182,17 @@ public abstract class ViewGroup extends View implements ViewParent, ViewManager
         }
     }
 
+    @Override
+    void dispatchCancelPendingInputEvents() {
+        super.dispatchCancelPendingInputEvents();
+
+        final View[] children = mChildren;
+        final int count = mChildrenCount;
+        for (int i = 0; i < count; i++) {
+            children[i].dispatchCancelPendingInputEvents();
+        }
+    }
+
     /**
      * When this property is set to true, this ViewGroup supports static transformations on
      * children; this causes