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_ 56
