content/public/browser/render_widget_host_view_mac_delegate.h

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