ash/wm/base_layout_manager.h

   1 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
   2 // Use of this source code is governed by a BSD-style license that can be
   3 // found in the LICENSE file.
   4
   5 #ifndef ASH_WM_BASE_LAYOUT_MANAGER_H_
   6 #define ASH_WM_BASE_LAYOUT_MANAGER_H_
   7
   8 #include <set>
   9
  10 #include "ash/ash_export.h"
  11 #include "ash/shell_observer.h"
  12 #include "ash/wm/window_state_observer.h"
  13 #include "base/basictypes.h"
  14 #include "base/compiler_specific.h"
  15 #include "ui/aura/client/activation_change_observer.h"
  16 #include "ui/aura/layout_manager.h"
  17 #include "ui/aura/window_observer.h"
  18 #include "ui/base/ui_base_types.h"
  19 #include "ui/events/event_handler.h"
  20
  21 namespace aura {
  22 class RootWindow;
  23 class Window;
  24 }
  25
  26 namespace ash {
  27 namespace wm {
  28 class WindowState;
  29 }
  30
  31 namespace internal {
  32
  33 // BaseLayoutManager is the simplest possible implementation for a window
  34 // layout manager. It listens for changes to kShowStateKey and resizes the
  35 // window appropriately.  Subclasses should be sure to invoke the base class
  36 // for adding and removing windows, otherwise show state will not be tracked
  37 // properly.
  38 class ASH_EXPORT BaseLayoutManager
  39     : public aura::LayoutManager,
  40       public aura::WindowObserver,
  41       public aura::client::ActivationChangeObserver,
  42       public ShellObserver,
  43       public wm::WindowStateObserver {
  44  public:
  45   typedef std::set<aura::Window*> WindowSet;
  46
  47   explicit BaseLayoutManager(aura::RootWindow* root_window);
  48   virtual ~BaseLayoutManager();
  49
  50   const WindowSet& windows() const { return windows_; }
  51
  52   // Given a |window| and tentative |restore_bounds|, returns new bounds that
  53   // ensure that at least a few pixels of the screen background are visible
  54   // outside the edges of the window.
  55   static gfx::Rect BoundsWithScreenEdgeVisible(aura::Window* window,
  56                                                const gfx::Rect& restore_bounds);
  57
  58   // aura::LayoutManager overrides:
  59   virtual void OnWindowResized() OVERRIDE;
  60   virtual void OnWindowAddedToLayout(aura::Window* child) OVERRIDE;
  61   virtual void OnWillRemoveWindowFromLayout(aura::Window* child) OVERRIDE;
  62   virtual void OnWindowRemovedFromLayout(aura::Window* child) OVERRIDE;
  63   virtual void OnChildWindowVisibilityChanged(aura::Window* child,
  64                                               bool visible) OVERRIDE;
  65   virtual void SetChildBounds(aura::Window* child,
  66                               const gfx::Rect& requested_bounds) OVERRIDE;
  67
  68   // aura::WindowObserver overrides:
  69   virtual void OnWindowDestroying(aura::Window* window) OVERRIDE;
  70   virtual void OnWindowBoundsChanged(aura::Window* window,
  71                                      const gfx::Rect& old_bounds,
  72                                      const gfx::Rect& new_bounds) OVERRIDE;
  73
  74   // aura::client::ActivationChangeObserver overrides:
  75   virtual void OnWindowActivated(aura::Window* gained_active,
  76                                  aura::Window* lost_active) OVERRIDE;
  77
  78   // ash::ShellObserver overrides:
  79   virtual void OnDisplayWorkAreaInsetsChanged() OVERRIDE;
  80
  81   // wm::WindowStateObserver overrides:
  82   virtual void OnWindowShowTypeChanged(wm::WindowState* window_state,
  83                                        wm::WindowShowType type) OVERRIDE;
  84
  85  protected:
  86   enum AdjustWindowReason {
  87     ADJUST_WINDOW_DISPLAY_SIZE_CHANGED,
  88     ADJUST_WINDOW_WORK_AREA_INSETS_CHANGED,
  89   };
  90
  91   // Invoked from OnWindowPropertyChanged() if |kShowStateKey| changes.
  92   virtual void ShowStateChanged(wm::WindowState* window_state,
  93                                 ui::WindowShowState last_show_state);
  94
  95   // Adjusts the window's bounds when the display area changes for given
  96   // window. This happens when the display size, work area insets or
  97   // the display on which the window exists has changed.
  98   // If this is called for a display size change (i.e. |reason|
  99   // is ADJUST_WINDOW_DISPLAY_SIZE_CHANGED), the non-maximized/non-fullscreen
 100   // windows are readjusted to make sure the window is completely within the
 101   // display region. Otherwise, it makes sure at least some parts of the window
 102   // is on display.
 103   virtual void AdjustAllWindowsBoundsForWorkAreaChange(
 104       AdjustWindowReason reason);
 105
 106   // Adjusts the sizes of the specific window in respond to a screen change or
 107   // display-area size change.
 108   virtual void AdjustWindowBoundsForWorkAreaChange(
 109       wm::WindowState* window_state,
 110       AdjustWindowReason reason);
 111
 112   aura::RootWindow* root_window() { return root_window_; }
 113
 114  private:
 115   // Update window bounds based on a change in show state.
 116   void UpdateBoundsFromShowState(wm::WindowState* controller);
 117
 118   // Set of windows we're listening to.
 119   WindowSet windows_;
 120
 121   aura::RootWindow* root_window_;
 122
 123   DISALLOW_COPY_AND_ASSIGN(BaseLayoutManager);
 124 };
 125
 126 }  // namespace internal
 127 }  // namespace ash
 128
 129 #endif  // ASH_WM_BASE_LAYOUT_MANAGER_H_