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_DELEGATE_H_ 6 #define UI_VIEWS_WIDGET_WIDGET_DELEGATE_H_ 7 8 #include <string> 9 #include <vector> 10 11 #include "ui/accessibility/ax_enums.h" 12 #include "ui/base/ui_base_types.h" 13 #include "ui/views/view.h" 14 15 namespace gfx { 16 class ImageSkia; 17 class Rect; 18 } 19 20 namespace views { 21 class BubbleDelegateView; 22 class ClientView; 23 class DialogDelegate; 24 class NonClientFrameView; 25 class View; 26 class Widget; 27 28 // Handles events on Widgets in context-specific ways. 29 class VIEWS_EXPORT WidgetDelegate { 30 public: 31 WidgetDelegate(); 32 33 // Sets the return value of CanActivate(). Default is true. 34 void set_can_activate(bool can_activate) { 35 can_activate_ = can_activate; 36 } 37 38 // Called whenever the widget's position changes. 39 virtual void OnWidgetMove(); 40 41 // Called with the display changes (color depth or resolution). 42 virtual void OnDisplayChanged(); 43 44 // Called when the work area (the desktop area minus task bars, 45 // menu bars, etc.) changes in size. 46 virtual void OnWorkAreaChanged(); 47 48 // Returns the view that should have the focus when the widget is shown. If 49 // NULL no view is focused. 50 virtual View* GetInitiallyFocusedView(); 51 52 virtual BubbleDelegateView* AsBubbleDelegate(); 53 virtual DialogDelegate* AsDialogDelegate(); 54 55 // Returns true if the window can ever be resized. 56 virtual bool CanResize() const; 57 58 // Returns true if the window can ever be maximized. 59 virtual bool CanMaximize() const; 60 61 // Returns true if the window can be activated. 62 virtual bool CanActivate() const; 63 64 // Returns the modal type that applies to the widget. Default is 65 // ui::MODAL_TYPE_NONE (not modal). 66 virtual ui::ModalType GetModalType() const; 67 68 virtual ui::AXRole GetAccessibleWindowRole() const; 69 70 // Returns the title to be read with screen readers. 71 virtual base::string16 GetAccessibleWindowTitle() const; 72 73 // Returns the text to be displayed in the window title. 74 virtual base::string16 GetWindowTitle() const; 75 76 // Returns true if the window should show a title in the title bar. 77 virtual bool ShouldShowWindowTitle() const; 78 79 // Returns true if the window should show a close button in the title bar. 80 virtual bool ShouldShowCloseButton() const; 81 82 // Returns true if the window should handle standard system commands, such as 83 // close, minimize, maximize. 84 virtual bool ShouldHandleSystemCommands() const; 85 86 // Returns the app icon for the window. On Windows, this is the ICON_BIG used 87 // in Alt-Tab list and Win7's taskbar. 88 virtual gfx::ImageSkia GetWindowAppIcon(); 89 90 // Returns the icon to be displayed in the window. 91 virtual gfx::ImageSkia GetWindowIcon(); 92 93 // Returns true if a window icon should be shown. 94 virtual bool ShouldShowWindowIcon() const; 95 96 // Execute a command in the window's controller. Returns true if the command 97 // was handled, false if it was not. 98 virtual bool ExecuteWindowsCommand(int command_id); 99 100 // Returns the window's name identifier. Used to identify this window for 101 // state restoration. 102 virtual std::string GetWindowName() const; 103 104 // Saves the window's bounds and "show" state. By default this uses the 105 // process' local state keyed by window name (See GetWindowName above). This 106 // behavior can be overridden to provide additional functionality. 107 virtual void SaveWindowPlacement(const gfx::Rect& bounds, 108 ui::WindowShowState show_state); 109 110 // Retrieves the window's bounds and "show" states. 111 // This behavior can be overridden to provide additional functionality. 112 virtual bool GetSavedWindowPlacement(const Widget* widget, 113 gfx::Rect* bounds, 114 ui::WindowShowState* show_state) const; 115 116 // Returns true if the window's size should be restored. If this is false, 117 // only the window's origin is restored and the window is given its 118 // preferred size. 119 // Default is true. 120 virtual bool ShouldRestoreWindowSize() const; 121 122 // Called when the window closes. The delegate MUST NOT delete itself during 123 // this call, since it can be called afterwards. See DeleteDelegate(). 124 virtual void WindowClosing() {} 125 126 // Called when the window is destroyed. No events must be sent or received 127 // after this point. The delegate can use this opportunity to delete itself at 128 // this time if necessary. 129 virtual void DeleteDelegate() {} 130 131 // Called when the user begins/ends to change the bounds of the window. 132 virtual void OnWindowBeginUserBoundsChange() {} 133 virtual void OnWindowEndUserBoundsChange() {} 134 135 // Returns the Widget associated with this delegate. 136 virtual Widget* GetWidget() = 0; 137 virtual const Widget* GetWidget() const = 0; 138 139 // Returns the View that is contained within this Widget. 140 virtual View* GetContentsView(); 141 142 // Called by the Widget to create the Client View used to host the contents 143 // of the widget. 144 virtual ClientView* CreateClientView(Widget* widget); 145 146 // Called by the Widget to create the NonClient Frame View for this widget. 147 // Return NULL to use the default one. 148 virtual NonClientFrameView* CreateNonClientFrameView(Widget* widget); 149 150 // Called by the Widget to create the overlay View for this widget. Return 151 // NULL for no overlay. The overlay View will fill the Widget and sit on top 152 // of the ClientView and NonClientFrameView (both visually and wrt click 153 // targeting). 154 virtual View* CreateOverlayView(); 155 156 // Returns true if the window can be notified with the work area change. 157 // Otherwise, the work area change for the top window will be processed by 158 // the default window manager. In some cases, like panel, we would like to 159 // manage the positions by ourselves. 160 virtual bool WillProcessWorkAreaChange() const; 161 162 // Returns true if window has a hit-test mask. 163 virtual bool WidgetHasHitTestMask() const; 164 165 // Provides the hit-test mask if HasHitTestMask above returns true. 166 virtual void GetWidgetHitTestMask(gfx::Path* mask) const; 167 168 // Returns true if focus should advance to the top level widget when 169 // tab/shift-tab is hit and on the last/first focusable view. Default returns 170 // false, which means tab/shift-tab never advance to the top level Widget. 171 virtual bool ShouldAdvanceFocusToTopLevelWidget() const; 172 173 // Returns true if event handling should descend into |child|. 174 // |location| is in terms of the Window. 175 virtual bool ShouldDescendIntoChildForEventHandling( 176 gfx::NativeView child, 177 const gfx::Point& location); 178 179 // Populates |panes| with accessible panes in this window that can 180 // be cycled through with keyboard focus. 181 virtual void GetAccessiblePanes(std::vector<View*>* panes) {} 182 183 protected: 184 virtual ~WidgetDelegate() {} 185 186 private: 187 View* default_contents_view_; 188 189 bool can_activate_; 190 191 DISALLOW_COPY_AND_ASSIGN(WidgetDelegate); 192 }; 193 194 // A WidgetDelegate implementation that is-a View. Used to override GetWidget() 195 // to call View's GetWidget() for the common case where a WidgetDelegate 196 // implementation is-a View. Note that WidgetDelegateView is not owned by 197 // view's hierarchy and is expected to be deleted on DeleteDelegate call. 198 class VIEWS_EXPORT WidgetDelegateView : public WidgetDelegate, public View { 199 public: 200 WidgetDelegateView(); 201 virtual ~WidgetDelegateView(); 202 203 // Overridden from WidgetDelegate: 204 virtual void DeleteDelegate() OVERRIDE; 205 virtual Widget* GetWidget() OVERRIDE; 206 virtual const Widget* GetWidget() const OVERRIDE; 207 208 private: 209 DISALLOW_COPY_AND_ASSIGN(WidgetDelegateView); 210 }; 211 212 } // namespace views 213 214 #endif // UI_VIEWS_WIDGET_WIDGET_DELEGATE_H_ 215