SyntheticGestureTarget implementation for injecting synthetic input events

content/browser/renderer_host/input/synthetic_gesture_target_android.h

+// Copyright 2013 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#ifndef CONTENT_BROWSER_RENDERER_HOST_INPUT_SYNTHETIC_GESTURE_TARGET_ANDROID_H_
+#define CONTENT_BROWSER_RENDERER_HOST_INPUT_SYNTHETIC_GESTURE_TARGET_ANDROID_H_
+
+#include "base/android/jni_android.h"
+#include "base/time/time.h"
+#include "content/browser/renderer_host/input/synthetic_gesture_target_base.h"
+
+namespace content {
+
+class ContentViewCoreImpl;
+class RenderWidgetHostViewAndroid;
+
+class SyntheticGestureTargetAndroid : public SyntheticGestureTargetBase {
+ public:
+  explicit SyntheticGestureTargetAndroid(
+      RenderWidgetHostViewAndroid* render_view,
+      base::android::ScopedJavaLocalRef<jobject> java_touch_event);

[aelias_OOO_until_Jul13, 2013/10/31 01:47:48]

I'm confused as to why this is taking a single touch event in the constructor. 
Isn't this class to set up a target that will receive a stream of many touch
events?

It looks like you're reusing the same touch event over and over.  But this isn't
what happens in reality and Android code may depend or eventually come to depend
on the fact that each touch event is different.  I think this should create a
different Java touch event object for each, and hold a Java local ref not a
global one.

[kouhei (in TOK), 2013/10/31 04:26:36]

java_touch_event is a SyntheticTouchEvent instance. SyntheticTouchEvent is a
factory for MotionEvent added in this CL. We are using new MotionEvent per touch
event.

[aelias_OOO_until_Jul13, 2013/10/31 08:52:42]

OK.  Can you please rename it to TouchEventSynthesizer then?

[kouhei (in TOK), 2013/11/05 01:32:25]

Done.

+  ~SyntheticGestureTargetAndroid();
+
+  virtual void QueueWebTouchEventToPlatform(
+      const WebKit::WebTouchEvent& web_touch,
+      const ui::LatencyInfo& latency_info) OVERRIDE;
+
+  // SyntheticGestureTarget:
+  virtual SyntheticGestureParams::GestureSourceType
+      GetDefaultSyntheticGestureSourceType() const OVERRIDE;
+  virtual bool SupportsSyntheticGestureSourceType(
+      SyntheticGestureParams::GestureSourceType gesture_source_type) const
+      OVERRIDE;
+
+ private:
+  // Enum values below need to be kept in sync with SyntheticTouchEvent.java
+  enum Action {
+    ActionInvalid = -1,
+    ActionStart = 0,
+    ActionMove = 1,
+    ActionCancel = 2,
+    ActionEnd = 3
+  };
+
+  void TouchSetPointer(JNIEnv* env, int index, int x, int y, int id);
+  void TouchInject(JNIEnv* env, Action action, int pointer_count);
+
+  base::android::ScopedJavaGlobalRef<jobject> java_touch_event_;
+
+  DISALLOW_COPY_AND_ASSIGN(SyntheticGestureTargetAndroid);
+};
+
+}  // namespace content
+
+#endif  // CONTENT_BROWSER_RENDERER_HOST_INPUT_SYNTHETIC_GESTURE_TARGET_ANDROID_H_