Support DWM switching....

chrome/views/non_client_view.h

 // Copyright (c) 2006-2008 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 CHROME_VIEWS_NON_CLIENT_VIEW_H_
 #define CHROME_VIEWS_NON_CLIENT_VIEW_H_
 
+#include "base/task.h"
 #include "chrome/views/view.h"
 #include "chrome/views/client_view.h"
 
 namespace gfx {
 class Path;
 }
 
 namespace views {
 
-///////////////////////////////////////////////////////////////////////////////
-// NonClientView
+////////////////////////////////////////////////////////////////////////////////
+// NonClientFrameView
 //
-//  An object implementing the NonClientView interface is a View that provides
-//  the "non-client" areas of a window. This is the area that typically
-//  encompasses the window frame - title bar, sizing borders and window
-//  controls. This interface provides methods that allow a specific
-//  presentation to define non-client areas for windows hit testing, the shape
-//  of the window, and other window-related information.
-//
-class NonClientView : public View {
+//  An object that subclasses NonClientFrameView is a View that renders and
+//  responds to events within the frame portions of the non-client area of a
+//  window. This view does _not_ contain the ClientView, but rather is a sibling
+//  of it.
+class NonClientFrameView : public views::View {
  public:
-  NonClientView();
-  virtual ~NonClientView();
-
   // Various edges of the frame border have a 1 px shadow along their edges; in
   // a few cases we shift elements based on this amount for visual appeal.
   static const int kFrameShadowThickness;
   // In restored mode, we draw a 1 px edge around the content area inside the
   // frame border.
   static const int kClientEdgeThickness;
 
+  void DisableInactiveRendering(bool disable) {
+    paint_as_active_ = disable;
+    if (!paint_as_active_)
+      SchedulePaint();
+  }
+
+  // Returns the bounds (in this View's parent's coordinates) that the client
+  // view should be laid out within.
+  virtual gfx::Rect GetBoundsForClientView() const = 0;
+
+  // Returns true if this FrameView should always use the custom frame,
+  // regardless of the system settings. An example is the Constrained Window,
+  // which is a child window and must always provide its own frame.
+  virtual bool AlwaysUseCustomFrame() const { return false; }
+
+  virtual gfx::Rect GetWindowBoundsForClientBounds(
+      const gfx::Rect& client_bounds) const = 0;
+  virtual gfx::Point GetSystemMenuPoint() const = 0;
+  virtual int NonClientHitTest(const gfx::Point& point) = 0;
+  virtual void GetWindowMask(const gfx::Size& size,
+                             gfx::Path* window_mask) = 0;
+  virtual void EnableClose(bool enable) = 0;
+  virtual void ResetWindowControls() = 0;
+
+ protected:
+  NonClientFrameView() : paint_as_active_(false) {}
+
+
+  // Helper for non-client view implementations to determine which area of the
+  // window border the specified |point| falls within. The other parameters are
+  // the size of the sizing edges, and whether or not the window can be
+  // resized.
+  int GetHTComponentForFrame(const gfx::Point& point,
+                             int top_resize_border_height,
+                             int resize_border_thickness,
+                             int top_resize_corner_height,
+                             int resize_corner_width,
+                             bool can_resize);
+
+  // Accessor for paint_as_active_.
+  bool paint_as_active() const { return paint_as_active_; }
+
+ private:
+  // True when the non-client view should always be rendered as if the window
+  // were active, regardless of whether or not the top level window actually
+  // is active.
+  bool paint_as_active_;
+};
+
+////////////////////////////////////////////////////////////////////////////////
+// NonClientView
+//
+//  The NonClientView is the logical root of all Views contained within a
+//  Window, except for the RootView which is its parent and of which it is the
+//  sole child. The NonClientView has two children, the NonClientFrameView which
+//  is responsible for painting and responding to events from the non-client
+//  portions of the window, and the ClientView, which is responsible for the
+//  same for the client area of the window:
+//
+//  +- views::Window ------------------------------------+
+//  | +- views::RootView ------------------------------+ |
+//  | | +- views::NonClientView ---------------------+ | |
+//  | | | +- views::NonClientFrameView subclass ---+ | | |
+//  | | | |                                        | | | |
+//  | | | | << all painting and event receiving >> | | | |
+//  | | | | << of the non-client areas of a     >> | | | |
+//  | | | | << views::Window.                   >> | | | |
+//  | | | |                                        | | | |
+//  | | | +----------------------------------------+ | | |
+//  | | | +- views::ClientView or subclass --------+ | | |
+//  | | | |                                        | | | |
+//  | | | | << all painting and event receiving >> | | | |
+//  | | | | << of the client areas of a         >> | | | |
+//  | | | | << views::Window.                   >> | | | |
+//  | | | |                                        | | | |
+//  | | | +----------------------------------------+ | | |
+//  | | +--------------------------------------------+ | |
+//  | +------------------------------------------------+ |
+//  +----------------------------------------------------+
+//
+// The NonClientFrameView and ClientView are siblings because due to theme
+// changes the NonClientFrameView may be replaced with different
+// implementations (e.g. during the switch from DWM/Aero-Glass to Vista Basic/
+// Classic rendering).
+//
+class NonClientView : public View {
+ public:
+  explicit NonClientView(Window* frame);
+  virtual ~NonClientView();
+
+  // Replaces the current NonClientFrameView (if any) with the specified one.
+  void SetFrameView(NonClientFrameView* frame_view);
+
   // Returns true if the ClientView determines that the containing window can be
   // closed, false otherwise.
   bool CanClose() const;
 
   // Called by the containing Window when it is closed.
   void WindowClosing();
 
+  // Called by the window when it receives a theme changed notification. Changes
+  // the content of the NonClientView to match what is required for the current
+  // system theme.
+  void SystemThemeChanged();
+
+  // Changes the frame from native to custom depending on the value of
+  // |use_native_frame|.
+  void SetUseNativeFrame(bool use_native_frame);
+
   // Returns true if the native window frame should be used, false if the
   // NonClientView provides its own frame implementation.
   bool UseNativeFrame() const;
 
-  // Calculates the bounds of the client area of the window assuming the
-  // window is sized to |width| and |height|.
-  virtual gfx::Rect CalculateClientAreaBounds(int width, int height) const;
+  // Prevents the window from being rendered as deactivated when |disable| is
+  // true, until called with |disable| false. Used when a sub-window is to be
+  // shown that shouldn't visually de-activate the window.
+  // Subclasses can override this to perform additional actions when this value
+  // changes.
+  void DisableInactiveRendering(bool disable);
 
-  // Calculates the size of window required to display a client area of the
-  // specified width and height.
-  virtual gfx::Size CalculateWindowSizeForClientSize(int width,
-                                                     int height) const;
+  // Returns the bounds of the window required to display the content area at
+  // the specified bounds.
+  gfx::Rect GetWindowBoundsForClientBounds(const gfx::Rect client_bounds) const;
 
   // Returns the point, in screen coordinates, where the system menu should
   // be shown so it shows up anchored to the system menu icon.
-  virtual gfx::Point GetSystemMenuPoint() const;
+  gfx::Point GetSystemMenuPoint() const;
 
   // Determines the windows HT* code when the mouse cursor is at the
   // specified point, in window coordinates.
-  virtual int NonClientHitTest(const gfx::Point& point);
+  int NonClientHitTest(const gfx::Point& point);
 
   // Returns a mask to be used to clip the top level window for the given
   // size. This is used to create the non-rectangular window shape.
-  virtual void GetWindowMask(const gfx::Size& size,
-                             gfx::Path* window_mask);
+  void GetWindowMask(const gfx::Size& size, gfx::Path* window_mask);
 
   // Toggles the enable state for the Close button (and the Close menu item in
   // the system menu).
-  virtual void EnableClose(bool enable);
+  void EnableClose(bool enable);
 
   // Tells the window controls as rendered by the NonClientView to reset
   // themselves to a normal state. This happens in situations where the
   // containing window does not receive a normal sequences of messages that
   // would lead to the controls returning to this normal state naturally, e.g.
   // when the window is maximized, minimized or restored.
-  virtual void ResetWindowControls();
-
-  // Prevents the non-client view from rendering as inactive when called with
-  // |disable| true, until called with false.
-  void set_paint_as_active(bool paint_as_active) { 
-    paint_as_active_ = paint_as_active;
-  }
+  void ResetWindowControls();
 
   // Get/Set client_view property.
   ClientView* client_view() const { return client_view_; }
   void set_client_view(ClientView* client_view) {
     client_view_ = client_view;
   }
 
   // NonClientView, View overrides:
   virtual gfx::Size GetPreferredSize();
   virtual void Layout();
 
  protected:
   // NonClientView, View overrides:
   virtual void ViewHierarchyChanged(bool is_add, View* parent, View* child);
 
-  // Helper for non-client view implementations to determine which area of the
-  // window border the specified |point| falls within. The other parameters are
-  // the size of the sizing edges, and whether or not the window can be
-  // resized.
-  int GetHTComponentForFrame(const gfx::Point& point,
-                             int top_resize_border_height,
-                             int resize_border_thickness,
-                             int top_resize_corner_height,
-                             int resize_corner_width,
-                             bool can_resize);
+ private:
+  // The frame that hosts this NonClientView.
+  Window* frame_;
 
-  // Accessor for paint_as_active_.
-  bool paint_as_active() const { return paint_as_active_; }
-
- private:
   // A ClientView object or subclass, responsible for sizing the contents view
   // of the window, hit testing and perhaps other tasks depending on the
   // implementation.
   ClientView* client_view_;
 
-  // True when the non-client view should always be rendered as if the window
-  // were active, regardless of whether or not the top level window actually
-  // is active.
-  bool paint_as_active_;
+  // The NonClientFrameView that renders the non-client portions of the window.
+  // This object is not owned by the view hierarchy because it can be replaced
+  // dynamically as the system settings change.
+  scoped_ptr<NonClientFrameView> frame_view_;
+
+  // Whether or not we should use the native frame.
+  bool use_native_frame_;
+
+  DISALLOW_COPY_AND_ASSIGN(NonClientView);
 };
 
 }  // namespace views
 
 #endif  // #ifndef CHROME_VIEWS_NON_CLIENT_VIEW_H_