Use gesture delegate for scrim component and add test

The GESTURE_DETECTOR property for the scrim is currently unused and
doesn't correctly pass motion events back to the mediator as it was
originally intended to. This patch correctly delegates event handling
to the mediator; there is no behavior change if the GESTURE_DETECTOR
property is null or not set. A test has also been added to ensure
events can be processed by the detector if set.

Bug: 1062099
Change-Id: Ia67f8f6dfa7b16d9f74a71bbe1a73994fe8ed034
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2305921Reviewed-by: Theresa  <twellington@chromium.org>
Commit-Queue: Matthew Jones <mdjones@chromium.org>
Cr-Commit-Position: refs/heads/master@{#790541}

components/browser_ui/widget/android/java/src/org/chromium/components/browser_ui/widget/scrim/ScrimTest.java

@@ -13,6 +13,8 @@ import static org.junit.Assert.assertTrue;
 
 import android.graphics.Color;
 import android.graphics.drawable.ColorDrawable;
+import android.view.GestureDetector;
+import android.view.MotionEvent;
 import android.view.View;
 import android.view.ViewGroup;
 import android.widget.FrameLayout;
@@ -36,6 +38,7 @@ import org.chromium.content_public.browser.test.util.CriteriaHelper;
 import org.chromium.ui.modelutil.PropertyModel;
 import org.chromium.ui.test.util.DummyUiActivityTestCase;
 
+import java.util.concurrent.ExecutionException;
 import java.util.concurrent.TimeoutException;
 
 /** This class tests the behavior of the scrim component. */
@@ -55,6 +58,9 @@ public class ScrimTest extends DummyUiActivityTestCase {
     private final Callback<Boolean> mVisibilityChangeCallback =
             (v) -> mVisibilityChangeCallbackHelper.notifyCalled();
 
+    private GestureDetector mCustomGestureDetector;
+    private CallbackHelper mDelegatedEventHelper;
+
     @Before
     public void setUp() throws TimeoutException {
         ThreadUtils.runOnUiThreadBlocking(() -> {
@@ -68,6 +74,16 @@ public class ScrimTest extends DummyUiActivityTestCase {
 
             mScrimCoordinator =
                     new ScrimCoordinator(getActivity(), mScrimDelegate, mParent, Color.RED);
+
+            mDelegatedEventHelper = new CallbackHelper();
+            mCustomGestureDetector =
+                    new GestureDetector(new GestureDetector.SimpleOnGestureListener() {
+                        @Override
+                        public boolean onDown(MotionEvent e) {
+                            mDelegatedEventHelper.notifyCalled();
+                            return true;
+                        }
+                    });
         });
     }
 
@@ -138,16 +154,43 @@ public class ScrimTest extends DummyUiActivityTestCase {
     @Test
     @SmallTest
     @Feature({"Scrim"})
-    public void testObserver_clickEvent() throws TimeoutException {
+    public void testObserver_clickEvent() throws ExecutionException, TimeoutException {
         showScrim(buildModel(true, false, true, Color.RED), false);
 
         int callCount = mScrimClickCallbackHelper.getCallCount();
-        ScrimMediator mediator = mScrimCoordinator.getMediatorForTesting();
         ScrimView scrimView = mScrimCoordinator.getViewForTesting();
-        ThreadUtils.runOnUiThreadBlocking(() -> mediator.onClick(scrimView));
+        ThreadUtils.runOnUiThreadBlocking(() -> scrimView.callOnClick());
         mScrimClickCallbackHelper.waitForCallback(callCount, 1);
     }
 
+    @Test
+    @SmallTest
+    @Feature({"Scrim"})
+    public void testGestureDetector() throws ExecutionException, TimeoutException {
+        ColorDrawable customDrawable = new ColorDrawable(Color.BLUE);
+        PropertyModel model =
+                new PropertyModel.Builder(ScrimProperties.ALL_KEYS)
+                        .with(ScrimProperties.TOP_MARGIN, 0)
+                        .with(ScrimProperties.AFFECTS_STATUS_BAR, false)
+                        .with(ScrimProperties.ANCHOR_VIEW, mAnchorView)
+                        .with(ScrimProperties.SHOW_IN_FRONT_OF_ANCHOR_VIEW, false)
+                        .with(ScrimProperties.CLICK_DELEGATE, mClickDelegate)
+                        .with(ScrimProperties.VISIBILITY_CALLBACK, mVisibilityChangeCallback)
+                        .with(ScrimProperties.BACKGROUND_COLOR, Color.RED)
+                        .with(ScrimProperties.BACKGROUND_DRAWABLE, customDrawable)
+                        .with(ScrimProperties.GESTURE_DETECTOR, mCustomGestureDetector)
+                        .build();
+        showScrim(model, false);
+
+        int gestureCallCount = mDelegatedEventHelper.getCallCount();
+        int callCount = mScrimClickCallbackHelper.getCallCount();
+        ScrimView scrimView = mScrimCoordinator.getViewForTesting();
+        ThreadUtils.runOnUiThreadBlocking(
+                () -> scrimView.dispatchTouchEvent(
+                        MotionEvent.obtain(0, 0, MotionEvent.ACTION_DOWN, 0, 0, 0)));
+        mDelegatedEventHelper.waitForCallback(gestureCallCount, 1);
+    }
+
     @Test
     @SmallTest
     @Feature({"Scrim"})

components/browser_ui/widget/android/java/src/org/chromium/components/browser_ui/widget/scrim/ScrimView.java

@@ -30,6 +30,7 @@ class ScrimView extends View {
     /**
      * @param context An Android {@link Context} for creating the view.
      * @param parent The {@link ViewGroup} the scrim should exist in.
+     * @param eventDelegate A means of passing motion events back to the mediator for processing.
      */
     public ScrimView(Context context, ViewGroup parent, @ColorInt int defaultColor,
             ScrimCoordinator.TouchEventDelegate eventDelegate) {
@@ -38,6 +39,7 @@ class ScrimView extends View {
         setFocusable(false);
         setImportantForAccessibility(IMPORTANT_FOR_ACCESSIBILITY_NO);
         mDefaultBackgroundColor = defaultColor;
+        mEventDelegate = eventDelegate;
 
         setAlpha(0.0f);
         setVisibility(View.GONE);
@@ -75,7 +77,7 @@ class ScrimView extends View {
 
     @Override
     public boolean onTouchEvent(MotionEvent e) {
-        if (mEventDelegate != null) return mEventDelegate.onTouchEvent(e);
+        if (mEventDelegate.onTouchEvent(e)) return true;
         return super.onTouchEvent(e);
     }
 }