render_widget_host_view_mac_delegate.h revision e5d81f57cb97b3b6b7fccc9c5610d21eb81db09d 
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 CONTENT_PUBLIC_BROWSER_RENDER_WIDGET_HOST_VIEW_MAC_DELEGATE_H_
6#define CONTENT_PUBLIC_BROWSER_RENDER_WIDGET_HOST_VIEW_MAC_DELEGATE_H_
7
8#import <Cocoa/Cocoa.h>
9
10// This protocol is used as a delegate for the NSView class used in the
11// hierarchy. There are two ways to extend the view:
12// - Implement the methods listed in the protocol below.
13// - Implement any method, and if the view is requested to perform that method
14//   and cannot, the delegate's implementation will be used.
15//
16// Like any Objective-C delegate, it is not retained by the delegator object.
17// The delegator object will call the -viewGone: method when it is going away.
18
19@class NSEvent;
20@protocol RenderWidgetHostViewMacDelegate
21@optional
22// Notification that the view is gone.
23- (void)viewGone:(NSView*)view;
24
25// Handle an event. All incoming key and mouse events flow through this delegate
26// method if implemented. Return YES if the event is fully handled, or NO if
27// normal processing should take place.
28- (BOOL)handleEvent:(NSEvent*)event;
29
30// Notification that a wheel event was unhandled.
31- (void)gotUnhandledWheelEvent;
32
33// Notification of scroll offset pinning.
34- (void)scrollOffsetPinnedToLeft:(BOOL)left toRight:(BOOL)right;
35
36// Notification of whether the view has a horizontal scrollbar.
37- (void)setHasHorizontalScrollbar:(BOOL)has_horizontal_scrollbar;
38
39// Provides validation of user interface items. If the return value is NO, then
40// the delegate is unaware of that item and |valid| is undefined.  Otherwise,
41// |valid| contains the validity of the specified item.
42- (BOOL)validateUserInterfaceItem:(id<NSValidatedUserInterfaceItem>)item
43                      isValidItem:(BOOL*)valid;
44
45@required
46// Notification of when a gesture begins/ends.
47- (void)beginGestureWithEvent:(NSEvent*)event;
48- (void)endGestureWithEvent:(NSEvent*)event;
49
50// This is a low level API which provides touches associated with an event.
51// It is used in conjunction with gestures to determine finger placement
52// on the trackpad.
53- (void)touchesMovedWithEvent:(NSEvent*)event;
54- (void)touchesBeganWithEvent:(NSEvent*)event;
55- (void)touchesCancelledWithEvent:(NSEvent*)event;
56- (void)touchesEndedWithEvent:(NSEvent*)event;
57
58// These methods control whether a given view is allowed to rubberband in the
59// given direction. This is inversely related to whether the view is allowed to
60// 2-finger history swipe in the given direction.
61- (BOOL)canRubberbandLeft:(NSView*)view;
62- (BOOL)canRubberbandRight:(NSView*)view;
63@end
64
65#endif  // CONTENT_PUBLIC_BROWSER_RENDER_WIDGET_HOST_VIEW_MAC_DELEGATE_H_
66