Attach panel while dragging to bring it in front of other panels.

ash/wm/toplevel_window_event_handler.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/toplevel_window_event_handler.h"
 
 #include "ash/shell.h"
 #include "ash/wm/property_util.h"
 #include "ash/wm/resize_shadow_controller.h"
 #include "ash/wm/window_resizer.h"
@@ skipping 41 matching lines @@
 // Wraps a WindowResizer and installs an observer on its target window.  When
 // the window is destroyed ResizerWindowDestroyed() is invoked back on the
 // ToplevelWindowEventHandler to clean up.
 class ToplevelWindowEventHandler::ScopedWindowResizer
     : public aura::WindowObserver {
  public:
   ScopedWindowResizer(ToplevelWindowEventHandler* handler,
                       WindowResizer* resizer);
   virtual ~ScopedWindowResizer();
 
+  WindowResizer* ReleaseResizer();
+
   WindowResizer* resizer() { return resizer_.get(); }
 
   // WindowObserver overrides:
   virtual void OnWindowPropertyChanged(aura::Window* window,
                                        const void* key,
                                        intptr_t old) OVERRIDE;
   virtual void OnWindowDestroying(aura::Window* window) OVERRIDE;
 
  private:
   ToplevelWindowEventHandler* handler_;
   scoped_ptr<WindowResizer> resizer_;
 
   DISALLOW_COPY_AND_ASSIGN(ScopedWindowResizer);
 };
 
 ToplevelWindowEventHandler::ScopedWindowResizer::ScopedWindowResizer(
     ToplevelWindowEventHandler* handler,
     WindowResizer* resizer)
     : handler_(handler),
       resizer_(resizer) {
   if (resizer_.get())
     resizer_->GetTarget()->AddObserver(this);
 }
 
 ToplevelWindowEventHandler::ScopedWindowResizer::~ScopedWindowResizer() {
   if (resizer_.get())
     resizer_->GetTarget()->RemoveObserver(this);
 }
 
+WindowResizer*
+ToplevelWindowEventHandler::ScopedWindowResizer::ReleaseResizer() {
+  if (resizer_.get())
+    resizer_->GetTarget()->RemoveObserver(this);
+  return resizer_.release();
+}
+
 void ToplevelWindowEventHandler::ScopedWindowResizer::OnWindowPropertyChanged(
     aura::Window* window,
     const void* key,
     intptr_t old) {
   if (!wm::IsWindowNormal(window))
     handler_->CompleteDrag(DRAG_COMPLETE, 0);
 }
 
 void ToplevelWindowEventHandler::ScopedWindowResizer::OnWindowDestroying(
     aura::Window* window) {
@@ skipping 215 matching lines @@
 void ToplevelWindowEventHandler::OnDisplayConfigurationChanging() {
   if (in_move_loop_) {
     move_cancelled_ = true;
     EndMoveLoop();
   } else if (window_resizer_.get()) {
     window_resizer_->resizer()->RevertDrag();
     window_resizer_.reset();
   }
 }
 
+void ToplevelWindowEventHandler::PassResizer(WindowResizerOwner* new_owner) {
+  DCHECK(window_resizer_.get());
+  new_owner->AcceptResizer(window_resizer_->ReleaseResizer(),
+                           in_gesture_drag_);
+  window_resizer_.reset();
+}
+
+void ToplevelWindowEventHandler::AcceptResizer(WindowResizer* resizer,
+                                               bool in_gesture_drag) {
+  window_resizer_.reset(new ScopedWindowResizer(this, resizer));
+  in_gesture_drag_ = in_gesture_drag;
+}
+
 void ToplevelWindowEventHandler::CreateScopedWindowResizer(
     aura::Window* window,
     const gfx::Point& point_in_parent,
     int window_component) {
   window_resizer_.reset();
   WindowResizer* resizer =
-      CreateWindowResizer(window, point_in_parent, window_component).release();
+      CreateWindowResizer(this, window, point_in_parent,
+                          window_component).release();
   if (resizer)
     window_resizer_.reset(new ScopedWindowResizer(this, resizer));
 }
 
 void ToplevelWindowEventHandler::CompleteDrag(DragCompletionStatus status,
                                               int event_flags) {
   scoped_ptr<ScopedWindowResizer> resizer(window_resizer_.release());
   if (resizer.get()) {
     if (status == DRAG_COMPLETE)
       resizer->resizer()->CompleteDrag(event_flags);
@@ skipping 113 matching lines @@
 void ToplevelWindowEventHandler::ResizerWindowDestroyed() {
   // We explicitly don't invoke RevertDrag() since that may do things to window.
   // Instead we destroy the resizer.
   window_resizer_.reset();
 
   // End the move loop. This does nothing if we're not in a move loop.
   EndMoveLoop();
 }
 
 }  // namespace ash