Draw web content area correctly on a phantom window for window dragging

ash/wm/workspace/phantom_window_controller.cc

 // Copyright (c) 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 "ash/wm/workspace/phantom_window_controller.h"
 
 #include "ash/shell.h"
 #include "ash/shell_window_ids.h"
 #include "ash/wm/coordinate_conversion.h"
 #include "third_party/skia/include/core/SkCanvas.h"
@@ skipping 72 matching lines @@
     window_->AddObserver(this);
   }
 
   virtual ~WindowPainter() {
     if (window_)
       window_->RemoveObserver(this);
   }
 
   // views::Painter overrides:
   virtual void Paint(gfx::Canvas* canvas, const gfx::Size& size) OVERRIDE {
-    // TODO(yusukes): Paint child windows of the |window_| correctly. Current
-    // code does not paint e.g. web content area in the window. crbug.com/141766
     if (window_ && window_->delegate())
       window_->delegate()->OnPaint(canvas);
   }
 
  private:
   // aura::WindowObserver overrides:
   virtual void OnWindowDestroyed(aura::Window* window) OVERRIDE {
     DCHECK_EQ(window_, window);
     window_ = NULL;
   }
 
   aura::Window* window_;
 
   DISALLOW_COPY_AND_ASSIGN(WindowPainter);
 };
 
 }  // namespace
 
 PhantomWindowController::PhantomWindowController(aura::Window* window)
     : window_(window),
       phantom_below_window_(NULL),
       phantom_widget_(NULL),
-      style_(STYLE_SHADOW) {
+      style_(STYLE_SHADOW),
+      layer_(NULL) {
 }
 
 PhantomWindowController::~PhantomWindowController() {
   Hide();
 }
 
 void PhantomWindowController::SetDestinationDisplay(
     const gfx::Display& dst_display) {
   dst_display_ = dst_display;
 }
 
+void PhantomWindowController::set_layer(ui::Layer* layer) {
+  // Cannot set a layer after the widget is initialized.
+  DCHECK(!phantom_widget_);
+  layer_ = layer;
+}
+
 void PhantomWindowController::Show(const gfx::Rect& bounds) {
+  if (layer_)
+    layer_->SetVisible(true);
   if (bounds == bounds_)
     return;
   bounds_ = bounds;
   if (!phantom_widget_) {
     // Show the phantom at the bounds of the window. We'll animate to the target
     // bounds.
     start_bounds_ = window_->GetBoundsInScreen();
     CreatePhantomWidget(start_bounds_);
   } else {
     start_bounds_ = phantom_widget_->GetWindowBoundsInScreen();
   }
   animation_.reset(new ui::SlideAnimation(this));
   animation_->Show();
 }
 
 void PhantomWindowController::SetBounds(const gfx::Rect& bounds) {
   DCHECK(IsShowing());
+  if (layer_)
+    layer_->SetVisible(true);
   animation_.reset();
   bounds_ = bounds;
   SetBoundsInternal(bounds);
 }
 
 void PhantomWindowController::Hide() {
   if (phantom_widget_)
     phantom_widget_->Close();
   phantom_widget_ = NULL;
+  if (layer_)
+    layer_->SetVisible(false);
 }
 
 bool PhantomWindowController::IsShowing() const {
   return phantom_widget_ != NULL;
 }
 
 void PhantomWindowController::set_style(Style style) {
   // Cannot change |style_| after the widget is initialized.
   DCHECK(!phantom_widget_);
   style_ = style;
@@ skipping 43 matching lines @@
           true, new WindowPainter(window_)));
       break;
   }
   phantom_widget_->SetContentsView(content_view);
   SetBoundsInternal(bounds);
   if (phantom_below_window_)
     phantom_widget_->StackBelow(phantom_below_window_);
   else
     phantom_widget_->StackAbove(window_);
   phantom_widget_->Show();
+
+  if (layer_) {
+    // When |window|'s root window and |layer_|'s original root window is not
+    // the same (e.g. a phantom window for window dragging), most ui::Layers in
+    // |layer_| except the web content area are not rendered at all. To work

[sky, 2012/08/13 20:56:32]

This seems weird. Can you talk with Antoine about this restriction.

[Yusuke Sato, 2012/08/15 21:18:23]

Done. Talked with him and added set_delegate call to
WorkspaceWindowResizer::RecreateWindowLayers().

Now the WindowPainter class is gone.

+    // around the issue, we continue to use WindowPainter to render non-web
+    // content part of the window.
+    // TODO(yusukes): Find a way to resolve the issue and remove WindowPainter.
+    aura::Window* window = phantom_widget_->GetNativeWindow();
+    window->layer()->Add(layer_);
+    window->layer()->StackAtTop(layer_);
+  }
+
   // Fade the window in.
   ui::Layer* layer = phantom_widget_->GetNativeWindow()->layer();
   layer->SetOpacity(0);
   ui::ScopedLayerAnimationSettings scoped_setter(layer->GetAnimator());
   layer->SetOpacity(1);
 }
 
 void PhantomWindowController::SetBoundsInternal(const gfx::Rect& bounds) {
   aura::Window* window = phantom_widget_->GetNativeWindow();
   aura::client::ScreenPositionClient* screen_position_client =
       aura::client::GetScreenPositionClient(window->GetRootWindow());
   if (screen_position_client && dst_display_.id() != -1)
     screen_position_client->SetBounds(window, bounds, dst_display_);
   else
     phantom_widget_->SetBounds(bounds);
 }
 
 }  // namespace internal
 }  // namespace ash