Beginnings of Window Modality support.

ui/aura_shell/modal_container_layout_manager.h

+// Copyright (c) 2011 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 UI_AURA_SHELL_MODAL_CONTAINER_LAYOUT_MANAGER_H_
+#define UI_AURA_SHELL_MODAL_CONTAINER_LAYOUT_MANAGER_H_
+#pragma once
+
+#include <vector>
+
+#include "base/basictypes.h"
+#include "base/compiler_specific.h"
+#include "base/memory/scoped_ptr.h"
+#include "ui/aura/layout_manager.h"
+#include "ui/aura/window_observer.h"
+#include "ui/aura_shell/aura_shell_export.h"
+#include "ui/aura_shell/modality_event_filter_delegate.h"
+#include "ui/gfx/compositor/layer_animation_observer.h"
+
+namespace aura {
+class Window;
+class EventFilter;
+}
+namespace gfx {
+class Rect;
+}
+namespace views {
+class Widget;
+}
+
+namespace aura_shell {
+namespace internal {
+
+// LayoutManager for the modal window container.
+class AURA_SHELL_EXPORT ModalContainerLayoutManager
+    : public aura::LayoutManager,
+      public aura::WindowObserver,
+      public ui::LayerAnimationObserver,
+      public ModalityEventFilterDelegate {
+ public:
+  explicit ModalContainerLayoutManager(aura::Window* container);
+  virtual ~ModalContainerLayoutManager();
+
+  // Overridden from aura::LayoutManager:
+  virtual void OnWindowResized() OVERRIDE;
+  virtual void OnWindowAddedToLayout(aura::Window* child) OVERRIDE;
+  virtual void OnWillRemoveWindowFromLayout(aura::Window* child) OVERRIDE;
+  virtual void OnChildWindowVisibilityChanged(aura::Window* child,
+                                              bool visibile) OVERRIDE;
+  virtual void SetChildBounds(aura::Window* child,
+                              const gfx::Rect& requested_bounds) OVERRIDE;
+
+  // Overridden from aura::WindowObserver:
+  virtual void OnPropertyChanged(aura::Window* window,
+                                 const char* key,
+                                 void* old) OVERRIDE;
+
+  // Overridden from ui::LayerAnimationObserver:
+  virtual void OnLayerAnimationEnded(
+      const ui::LayerAnimationSequence* sequence) OVERRIDE;
+  virtual void OnLayerAnimationAborted(
+      const ui::LayerAnimationSequence* sequence) OVERRIDE;
+  virtual void OnLayerAnimationScheduled(
+      const ui::LayerAnimationSequence* sequence) OVERRIDE;
+
+  // Overridden from ModalityEventFilterDelegate:
+  virtual bool CanWindowReceiveEvents(aura::Window* window) OVERRIDE;
+
+ private:
+  void AddModalWindow(aura::Window* window);
+  void RemoveModalWindow(aura::Window* window);
+
+  void CreateModalScreen();
+  void DestroyModalScreen();
+  void HideModalScreen();
+
+  aura::Window* modal_window() {
+    return !modal_windows_.empty() ? modal_windows_.back() : NULL;
+  }
+
+  // The container that owns the layout manager.
+  aura::Window* container_;
+
+  // A "screen" widget that dims the windows behind the modal window(s) being
+  // shown in |container_|.
+  views::Widget* modal_screen_;
+
+  // A stack of modal windows. Only the topmost can receive events.
+  std::vector<aura::Window*> modal_windows_;
+
+  // An event filter that enforces the modality of the topmost window in
+  // |modal_windows_|. The event filter is attached when a modal window is
+  // added, and removed when the last is closed.
+  scoped_ptr<aura::EventFilter> modality_filter_;
+
+  DISALLOW_COPY_AND_ASSIGN(ModalContainerLayoutManager);
+};
+
+}  // namespace internal
+}  // namespace aura_shell
+
+#endif  // UI_AURA_SHELL_MODAL_CONTAINER_LAYOUT_MANAGER_H_