[Mac] "Refactor" DraggableButton into a mixin and impl.

chrome/browser/ui/cocoa/draggable_button.h

-// Copyright (c) 2010 The Chromium Authors. All rights reserved.
+// Copyright (c) 2011 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.
 
 #import <Cocoa/Cocoa.h>
 
+#import "base/memory/scoped_nsobject.h"
+#import "chrome/browser/ui/cocoa/draggable_button_mixin.h"
+
 // Class for buttons that can be drag sources. If the mouse is clicked and moved
 // more than a given distance, this class will call |-beginDrag:| instead of
 // |-performClick:|. Subclasses should override these two methods.
-@interface DraggableButton : NSButton {
+@interface DraggableButton : NSButton<DraggableButtonMixin> {
  @private
-  BOOL draggable_;        // Is this a draggable type of button?
-  BOOL actionHasFired_;   // Has the action already fired for this click?
-  BOOL actsOnMouseDown_;  // Does button action happen on mouse down when
-                          // possible?
-  NSTimeInterval durationMouseWasDown_;
-  NSTimeInterval whenMouseDown_;
+  scoped_nsobject<DraggableButtonImpl> draggableButtonImpl_;
 }
 
-@property NSTimeInterval durationMouseWasDown;
+@property(readonly, nonatomic) DraggableButtonImpl* draggableButton;
 
-@property NSTimeInterval whenMouseDown;
-
-// Whether the action has already fired for this click.
-@property(nonatomic) BOOL actionHasFired;
-
-// Enable or disable dragability for special buttons like "Other Bookmarks".
-@property(nonatomic) BOOL draggable;
-
-// If it has a popup menu, for example, we want to perform the action on mouse
-// down, if possible (as long as user still gets chance to drag, if
-// appropriate).
-@property(nonatomic) BOOL actsOnMouseDown;
-
-// Called when a drag should start. Subclasses must override this to do any
-// pasteboard manipulation and begin the drag, usually with
-// -dragImage:at:offset:event:.  Subclasses must call one of the blocking
-// -drag* methods of NSView when overriding this method.
-- (void)beginDrag:(NSEvent*)dragEvent;
-
-
-// Override if you want to do any extra work on mouseUp, after a mouseDown
-// action has already fired.
-- (void)secondaryMouseUpAction:(BOOL)wasInside;
-
-// This is called internally.
-// Decides if we now have enough information to stop tracking the mouse.
-// It's the function below, deltaIndicatesDragStartWithXDelta. however, that
-// decides whether it's a drag or not.
-// Override if you want to do something tricky when making the decision.
-// Default impl returns YES if ABS(xDelta) or ABS(yDelta) >= their respective
-// hysteresis limit.
-- (BOOL)deltaIndicatesConclusionReachedWithXDelta:(float)xDelta
-                                           yDelta:(float)yDelta
-                                      xHysteresis:(float)xHysteresis
-                                      yHysteresis:(float)yHysteresis;
-
-// This is called internally.
-// Decides whether we should treat the click as a cue to start dragging, or
-// instead call the mouseDown/mouseUp handler as appropriate.
-// Override if you want to do something tricky when making the decision.
-// Default impl returns YES if ABS(xDelta) or ABS(yDelta) >= their respective
-// hysteresis limit.
-- (BOOL)deltaIndicatesDragStartWithXDelta:(float)xDelta
-                                   yDelta:(float)yDelta
-                              xHysteresis:(float)xHysteresis
-                              yHysteresis:(float)yHysteresis;
-
-
-@end  // @interface DraggableButton
-
-@interface DraggableButton (Private)
-
-// Resets the draggable state of the button after dragging is finished.  This is
-// called by DraggableButton when the beginDrag call returns, it should not be
-// called by the subclass.
-- (void)endDrag;
-
-// Called internally if the actsOnMouseDown property is set.
-// Fires the button's action and tracks the click.
-- (void)performMouseDownAction:(NSEvent*)theEvent;
-
-
-@end  // @interface DraggableButton(Private)
+@end