Introduce ViewRoot to forward input/view events to native

ui/android/view_android.cc

 // Copyright 2016 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.
 
 #include "ui/android/view_android.h"
 
 #include <algorithm>
 
 #include "base/android/jni_android.h"
 #include "cc/layers/layer.h"
 #include "jni/ViewAndroidDelegate_jni.h"
 #include "ui/android/window_android.h"
 #include "ui/display/display.h"
 #include "ui/display/screen.h"
 
 namespace ui {
 
+using base::android::JavaParamRef;
 using base::android::JavaRef;
 using base::android::ScopedJavaLocalRef;
 
 ViewAndroid::ScopedAnchorView::ScopedAnchorView(
     JNIEnv* env,
     const JavaRef<jobject>& jview,
     const JavaRef<jobject>& jdelegate)
     : view_(env, jview.obj()), delegate_(env, jdelegate.obj()) {
   // If there's a view, then we need a delegate to remove it.
   DCHECK(!jdelegate.is_null() || jview.is_null());
@@ skipping 33 matching lines @@
   view_.reset();
   delegate_.reset();
 }
 
 const base::android::ScopedJavaLocalRef<jobject>
 ViewAndroid::ScopedAnchorView::view() const {
   JNIEnv* env = base::android::AttachCurrentThread();
   return view_.get(env);
 }
 
-ViewAndroid::ViewAndroid(const JavaRef<jobject>& delegate)
-    : parent_(nullptr)
-    , delegate_(base::android::AttachCurrentThread(),
-                delegate.obj()) {}
-
 ViewAndroid::ViewAndroid() : parent_(nullptr) {}
 
 ViewAndroid::~ViewAndroid() {
   RemoveFromParent();
 
   for (std::list<ViewAndroid*>::iterator it = children_.begin();
        it != children_.end(); it++) {
     DCHECK_EQ((*it)->parent_, this);
     (*it)->parent_ = nullptr;
   }
 }
 
 void ViewAndroid::SetDelegate(const JavaRef<jobject>& delegate) {
+  // A ViewAndroid may have its own delegate or otherwise will
+  // use the next available parent's delegate.
   JNIEnv* env = base::android::AttachCurrentThread();
   delegate_ = JavaObjectWeakGlobalRef(env, delegate);
+  Java_ViewAndroidDelegate_setNativePointer(env,

[boliu, 2016/11/15 04:51:03]

delegate has a many-to-one relationship with view, right? don't think this will
work

[Jinsuk Kim, 2016/11/15 16:47:44]

My intention was to maintain only one handler per each api to keep one-to-one
mapping. 

+                                            delegate,
+                                            reinterpret_cast<jlong>(this));
 }
 
 void ViewAndroid::AddChild(ViewAndroid* child) {
   DCHECK(child);
   DCHECK(std::find(children_.begin(), children_.end(), child) ==
          children_.end());
 
   children_.push_back(child);
   if (child->parent_)
     child->RemoveFromParent();
@@ skipping 71 matching lines @@
 bool ViewAndroid::StartDragAndDrop(const JavaRef<jstring>& jtext,
                                    const JavaRef<jobject>& jimage) {
   ScopedJavaLocalRef<jobject> delegate(GetViewAndroidDelegate());
   if (delegate.is_null())
     return false;
   JNIEnv* env = base::android::AttachCurrentThread();
   return Java_ViewAndroidDelegate_startDragAndDrop(env, delegate, jtext,
                                                    jimage);
 }
 
+void ViewAndroid::OnPhysicalBackingSizeChanged(
+    JNIEnv* env,
+    const JavaParamRef<jobject>& obj,
+    jint width, jint height) {
+  if (!physical_backing_size_changed_handler_.is_null()) {
+    physical_backing_size_changed_handler_.Run(width, height);
+    return;
+  }
+}
+
+// static
+bool ViewAndroid::RegisterViewAndroid(JNIEnv* env) {
+  return RegisterNativesImpl(env);
+}
+
 }  // namespace ui