ui/views/widget/widget_observer.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 UI_VIEWS_WIDGET_WIDGET_OBSERVER_H_
   6 #define UI_VIEWS_WIDGET_WIDGET_OBSERVER_H_
   7
   8 #include "ui/views/views_export.h"
   9
  10 namespace gfx {
  11 class Rect;
  12 }
  13
  14 namespace views {
  15
  16 class Widget;
  17 class View;
  18
  19 // Observers can listen to various events on the Widgets.
  20 class VIEWS_EXPORT WidgetObserver {
  21  public:
  22   // The closing notification is sent immediately in response to (i.e. in the
  23   // same call stack as) a request to close the Widget (via Close() or
  24   // CloseNow()).
  25   virtual void OnWidgetClosing(Widget* widget) {}
  26
  27   // Invoked after notification is received from the event loop that the native
  28   // widget has been created.
  29   virtual void OnWidgetCreated(Widget* widget) {}
  30
  31   // The destroying event occurs immediately before the widget is destroyed.
  32   // This typically occurs asynchronously with respect the the close request, as
  33   // a result of a later invocation from the event loop.
  34   virtual void OnWidgetDestroying(Widget* widget) {}
  35
  36   // Invoked after notification is received from the event loop that the native
  37   // widget has been destroyed.
  38   virtual void OnWidgetDestroyed(Widget* widget) {}
  39
  40   virtual void OnWidgetVisibilityChanging(Widget* widget, bool visible) {}
  41
  42   virtual void OnWidgetVisibilityChanged(Widget* widget, bool visible) {}
  43
  44   virtual void OnWidgetActivationChanged(Widget* widget, bool active) {}
  45
  46   virtual void OnWidgetBoundsChanged(Widget* widget,
  47                                      const gfx::Rect& new_bounds) {}
  48
  49  protected:
  50   virtual ~WidgetObserver() {}
  51 };
  52
  53 }  // namespace views
  54
  55 #endif  // UI_VIEWS_WIDGET_WIDGET_OBSERVER_H_