Add observers for DIP scale change.

content/browser/android/content_view_core_impl.cc

 // Copyright 2012 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 "content/browser/android/content_view_core_impl.h"
 
 #include <stddef.h>
 
 #include "base/android/jni_android.h"
 #include "base/android/jni_array.h"
@@ skipping 191 matching lines @@
     content::WebContents* web_contents) {
   return ContentViewCoreImpl::FromWebContents(web_contents);
 }
 
 ContentViewCoreImpl::ContentViewCoreImpl(
     JNIEnv* env,
     const JavaRef<jobject>& obj,
     WebContents* web_contents,
     const JavaRef<jobject>& view_android_delegate,
     ui::WindowAndroid* window_android,
+    float dpi_scale,
     const JavaRef<jobject>& java_bridge_retained_object_set)
     : WebContentsObserver(web_contents),
       java_ref_(env, obj),
       view_(view_android_delegate),
       web_contents_(static_cast<WebContentsImpl*>(web_contents)),
       page_scale_(1),
-      dpi_scale_(ui::GetScaleFactorForNativeView(&view_)),
+      dpi_scale_(dpi_scale),
       device_orientation_(0),
       accessibility_enabled_(false) {
   CHECK(web_contents) <<
       "A ContentViewCoreImpl should be created with a valid WebContents.";
   DCHECK(window_android);
   DCHECK(!view_android_delegate.is_null());
   window_android->AddChild(&view_);
   view_.SetLayer(cc::Layer::Create());
   gfx::Size physical_size(
       Java_ContentViewCore_getPhysicalBackingWidthPix(env, obj),
@@ skipping 567 matching lines @@
 }
 
 float ContentViewCoreImpl::GetTopControlsHeightDip() const {
   return GetTopControlsHeightPix() / dpi_scale();
 }
 
 float ContentViewCoreImpl::GetBottomControlsHeightDip() const {
   return GetBottomControlsHeightPix() / dpi_scale();
 }
 
+void ContentViewCoreImpl::SendScreenRectsAndResizeWidget() {
+  RenderWidgetHostViewAndroid* view = GetRenderWidgetHostViewAndroid();
+  if (view) {
+    // |SendScreenRects()| indirectly calls GetViewSize() that asks Java layer.
+    web_contents_->SendScreenRects();
+    view->WasResized();
+  }
+}
+
 void ContentViewCoreImpl::MoveRangeSelectionExtent(const gfx::PointF& extent) {
   if (!web_contents_)
     return;
 
   web_contents_->MoveRangeSelectionExtent(gfx::ToRoundedPoint(extent));
 }
 
 void ContentViewCoreImpl::SelectBetweenCoordinates(const gfx::PointF& base,
                                                    const gfx::PointF& extent) {
   if (!web_contents_)
@@ skipping 45 matching lines @@
 WebContents* ContentViewCoreImpl::GetWebContents() const {
   return web_contents_;
 }
 
 void ContentViewCoreImpl::SetFocus(JNIEnv* env,
                                    const JavaParamRef<jobject>& obj,
                                    jboolean focused) {
   SetFocusInternal(focused);
 }
 
+void ContentViewCoreImpl::SetDIPScale(JNIEnv* env,
+                                      const JavaParamRef<jobject>& obj,
+                                      jfloat dpi_scale) {
+  if (dpi_scale_ != dpi_scale) {

[boliu, 2016/10/19 20:49:07]

nit: general pattern is write it as an early out
if (old == new)
  return;

so the rest of the function doesn't need to be indented

[Tima Vaisburd, 2016/10/25 01:51:43]

Done.

+    dpi_scale_ = dpi_scale;
+    SendScreenRectsAndResizeWidget();
+  }
+}
+
 void ContentViewCoreImpl::SetFocusInternal(bool focused) {
   if (!GetRenderWidgetHostViewAndroid())
     return;
 
   if (focused)
     GetRenderWidgetHostViewAndroid()->Focus();
   else
     GetRenderWidgetHostViewAndroid()->Blur();
 }
 
@@ skipping 348 matching lines @@
 void ContentViewCoreImpl::RemoveJavascriptInterface(
     JNIEnv* env,
     const JavaParamRef<jobject>& /* obj */,
     const JavaParamRef<jstring>& name) {
   java_bridge_dispatcher_host_->RemoveNamedObject(
       ConvertJavaStringToUTF8(env, name));
 }
 
 void ContentViewCoreImpl::WasResized(JNIEnv* env,
                                      const JavaParamRef<jobject>& obj) {
-  RenderWidgetHostViewAndroid* view = GetRenderWidgetHostViewAndroid();
   gfx::Size physical_size(
       Java_ContentViewCore_getPhysicalBackingWidthPix(env, obj),
       Java_ContentViewCore_getPhysicalBackingHeightPix(env, obj));
   view_.GetLayer()->SetBounds(physical_size);
 
-  if (view) {
-    web_contents_->SendScreenRects();
-    view->WasResized();
-  }
+  SendScreenRectsAndResizeWidget();
 }
 
 long ContentViewCoreImpl::GetNativeImeAdapter(
     JNIEnv* env,
     const JavaParamRef<jobject>& obj) {
   RenderWidgetHostViewAndroid* rwhva = GetRenderWidgetHostViewAndroid();
   if (!rwhva)
     return 0;
   return rwhva->GetNativeImeAdapter();
 }
@@ skipping 289 matching lines @@
   if (!obj.is_null())
     Java_ContentViewCore_onOverscrollRefreshReset(env, obj);
 }
 
 // This is called for each ContentView.
 jlong Init(JNIEnv* env,
            const JavaParamRef<jobject>& obj,
            const JavaParamRef<jobject>& web_contents,
            const JavaParamRef<jobject>& view_android_delegate,
            jlong window_android,
+           jfloat dipScale,
            const JavaParamRef<jobject>& retained_objects_set) {
   ContentViewCoreImpl* view = new ContentViewCoreImpl(
       env, obj, WebContents::FromJavaWebContents(web_contents),
       view_android_delegate,
-      reinterpret_cast<ui::WindowAndroid*>(window_android),
+      reinterpret_cast<ui::WindowAndroid*>(window_android), dipScale,
       retained_objects_set);
   return reinterpret_cast<intptr_t>(view);
 }
 
 static ScopedJavaLocalRef<jobject> FromWebContentsAndroid(
     JNIEnv* env,
     const JavaParamRef<jclass>& clazz,
     const JavaParamRef<jobject>& jweb_contents) {
   WebContents* web_contents = WebContents::FromJavaWebContents(jweb_contents);
   if (!web_contents)
     return ScopedJavaLocalRef<jobject>();
 
   ContentViewCore* view = ContentViewCore::FromWebContents(web_contents);
   if (!view)
     return ScopedJavaLocalRef<jobject>();
 
   return view->GetJavaObject();
 }
 
 bool RegisterContentViewCore(JNIEnv* env) {
   return RegisterNativesImpl(env);
 }
 
 }  // namespace content