// Copyright (c) 2012 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_VIEWS_WIDGET_WIDGET_DELEGATE_H_
#define UI_VIEWS_WIDGET_WIDGET_DELEGATE_H_
#include <string>
#include <vector>
#include "ui/accessibility/ax_enums.h"
#include "ui/base/ui_base_types.h"
#include "ui/views/view.h"
namespace gfx {
class ImageSkia;
class Rect;
}
namespace views {
class BubbleDelegateView;
class ClientView;
class DialogDelegate;
class NonClientFrameView;
class View;
class Widget;
// Handles events on Widgets in context-specific ways.
class VIEWS_EXPORT WidgetDelegate {
public:
WidgetDelegate();
// Called whenever the widget's position changes.
virtual void OnWidgetMove();
// Called with the display changes (color depth or resolution).
virtual void OnDisplayChanged();
// Called when the work area (the desktop area minus task bars,
// menu bars, etc.) changes in size.
virtual void OnWorkAreaChanged();
// Returns the view that should have the focus when the widget is shown. If
// NULL no view is focused.
virtual View* GetInitiallyFocusedView();
virtual BubbleDelegateView* AsBubbleDelegate();
virtual DialogDelegate* AsDialogDelegate();
// Returns true if the window can ever be resized.
virtual bool CanResize() const;
// Returns true if the window can ever be maximized.
virtual bool CanMaximize() const;
// Returns true if the window can be activated.
virtual bool CanActivate() const;
// Returns the modal type that applies to the widget. Default is
// ui::MODAL_TYPE_NONE (not modal).
virtual ui::ModalType GetModalType() const;
virtual ui::AXRole GetAccessibleWindowRole() const;
// Returns the title to be read with screen readers.
virtual base::string16 GetAccessibleWindowTitle() const;
// Returns the text to be displayed in the window title.
virtual base::string16 GetWindowTitle() const;
// Returns true if the window should show a title in the title bar.
virtual bool ShouldShowWindowTitle() const;
// Returns true if the window should show a close button in the title bar.
virtual bool ShouldShowCloseButton() const;
// Returns true if the window should handle standard system commands, such as
// close, minimize, maximize.
virtual bool ShouldHandleSystemCommands() const;
// Returns the app icon for the window. On Windows, this is the ICON_BIG used
// in Alt-Tab list and Win7's taskbar.
virtual gfx::ImageSkia GetWindowAppIcon();
// Returns the icon to be displayed in the window.
virtual gfx::ImageSkia GetWindowIcon();
// Returns true if a window icon should be shown.
virtual bool ShouldShowWindowIcon() const;
// Execute a command in the window's controller. Returns true if the command
// was handled, false if it was not.
virtual bool ExecuteWindowsCommand(int command_id);
// Returns the window's name identifier. Used to identify this window for
// state restoration.
virtual std::string GetWindowName() const;
// Saves the window's bounds and "show" state. By default this uses the
// process' local state keyed by window name (See GetWindowName above). This
// behavior can be overridden to provide additional functionality.
virtual void SaveWindowPlacement(const gfx::Rect& bounds,
ui::WindowShowState show_state);
// Retrieves the window's bounds and "show" states.
// This behavior can be overridden to provide additional functionality.
virtual bool GetSavedWindowPlacement(const Widget* widget,
gfx::Rect* bounds,
ui::WindowShowState* show_state) const;
// Returns true if the window's size should be restored. If this is false,
// only the window's origin is restored and the window is given its
// preferred size.
// Default is true.
virtual bool ShouldRestoreWindowSize() const;
// Called when the window closes. The delegate MUST NOT delete itself during
// this call, since it can be called afterwards. See DeleteDelegate().
virtual void WindowClosing() {}
// Called when the window is destroyed. No events must be sent or received
// after this point. The delegate can use this opportunity to delete itself at
// this time if necessary.
virtual void DeleteDelegate() {}
// Called when the user begins/ends to change the bounds of the window.
virtual void OnWindowBeginUserBoundsChange() {}
virtual void OnWindowEndUserBoundsChange() {}
// Returns the Widget associated with this delegate.
virtual Widget* GetWidget() = 0;
virtual const Widget* GetWidget() const = 0;
// Returns the View that is contained within this Widget.
virtual View* GetContentsView();
// Called by the Widget to create the Client View used to host the contents
// of the widget.
virtual ClientView* CreateClientView(Widget* widget);
// Called by the Widget to create the NonClient Frame View for this widget.
// Return NULL to use the default one.
virtual NonClientFrameView* CreateNonClientFrameView(Widget* widget);
// Called by the Widget to create the overlay View for this widget. Return
// NULL for no overlay. The overlay View will fill the Widget and sit on top
// of the ClientView and NonClientFrameView (both visually and wrt click
// targeting).
virtual View* CreateOverlayView();
// Returns true if the window can be notified with the work area change.
// Otherwise, the work area change for the top window will be processed by
// the default window manager. In some cases, like panel, we would like to
// manage the positions by ourselves.
virtual bool WillProcessWorkAreaChange() const;
// Returns true if window has a hit-test mask.
virtual bool WidgetHasHitTestMask() const;
// Provides the hit-test mask if HasHitTestMask above returns true.
virtual void GetWidgetHitTestMask(gfx::Path* mask) const;
// Returns true if focus should advance to the top level widget when
// tab/shift-tab is hit and on the last/first focusable view. Default returns
// false, which means tab/shift-tab never advance to the top level Widget.
virtual bool ShouldAdvanceFocusToTopLevelWidget() const;
// Returns true if event handling should descend into |child|.
// |location| is in terms of the Window.
virtual bool ShouldDescendIntoChildForEventHandling(
gfx::NativeView child,
const gfx::Point& location);
// Populates |panes| with accessible panes in this window that can
// be cycled through with keyboard focus.
virtual void GetAccessiblePanes(std::vector<View*>* panes) {}
protected:
virtual ~WidgetDelegate() {}
private:
View* default_contents_view_;
DISALLOW_COPY_AND_ASSIGN(WidgetDelegate);
};
// A WidgetDelegate implementation that is-a View. Used to override GetWidget()
// to call View's GetWidget() for the common case where a WidgetDelegate
// implementation is-a View. Note that WidgetDelegateView is not owned by
// view's hierarchy and is expected to be deleted on DeleteDelegate call.
class VIEWS_EXPORT WidgetDelegateView : public WidgetDelegate, public View {
public:
WidgetDelegateView();
virtual ~WidgetDelegateView();
// Overridden from WidgetDelegate:
virtual void DeleteDelegate() OVERRIDE;
virtual Widget* GetWidget() OVERRIDE;
virtual const Widget* GetWidget() const OVERRIDE;
private:
DISALLOW_COPY_AND_ASSIGN(WidgetDelegateView);
};
} // namespace views
#endif // UI_VIEWS_WIDGET_WIDGET_DELEGATE_H_