1 // Copyright 2014 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_BROWSER_FRAME_HOST_FRAME_ACCESSIBILITY_H_ 6 #define CONTENT_BROWSER_FRAME_HOST_FRAME_ACCESSIBILITY_H_ 7 8 #include <vector> 9 10 #include "base/basictypes.h" 11 #include "base/memory/singleton.h" 12 #include "content/common/content_export.h" 13 14 namespace content { 15 16 class RenderFrameHostImpl; 17 18 // This singleton class maintains the mappings necessary to link child frames 19 // and guest frames into a single tree for accessibility. This class is only 20 // used if accessibility is enabled. 21 class CONTENT_EXPORT FrameAccessibility { 22 public: 23 static FrameAccessibility* GetInstance(); 24 25 // Add a mapping between an accessibility node of |parent_frame_host| 26 // and the child frame with the given frame tree node id, in the same 27 // frame tree. 28 void AddChildFrame(RenderFrameHostImpl* parent_frame_host, 29 int accessibility_node_id, 30 int64 child_frame_tree_node_id); 31 32 // Add a mapping between an accessibility node of |parent_frame_host| 33 // and the main frame of the guest Webcontents with the given 34 // browser plugin instance id. 35 void AddGuestWebContents(RenderFrameHostImpl* parent_frame_host, 36 int accessibility_node_id, 37 int browser_plugin_instance_id); 38 39 // This is called when a RenderFrameHostImpl is deleted, so invalid 40 // mappings can be removed from this data structure. 41 void OnRenderFrameHostDestroyed(RenderFrameHostImpl* render_frame_host); 42 43 // Given a parent RenderFrameHostImpl and an accessibility node id, look up 44 // a child frame or guest frame that was previously associated with this 45 // frame and node id. If a mapping exists, return the resulting frame if 46 // it's valid. If it doesn't resolve to a valid RenderFrameHostImpl, 47 // returns NULL. 48 RenderFrameHostImpl* GetChild(RenderFrameHostImpl* parent_frame_host, 49 int accessibility_node_id); 50 51 // Given a RenderFrameHostImpl, check the mapping table to see if it's 52 // the child of a node in some other frame. If so, return true and 53 // set the parent frame and accessibility node id in the parent frame, 54 // otherwise return false. 55 bool GetParent(RenderFrameHostImpl* child_frame_host, 56 RenderFrameHostImpl** out_parent_frame_host, 57 int* out_accessibility_node_id); 58 59 private: 60 FrameAccessibility(); 61 virtual ~FrameAccessibility(); 62 63 struct ChildFrameMapping { 64 ChildFrameMapping(); 65 66 RenderFrameHostImpl* parent_frame_host; 67 int accessibility_node_id; 68 int64 child_frame_tree_node_id; 69 int browser_plugin_instance_id; 70 }; 71 72 std::vector<ChildFrameMapping> mappings_; 73 74 friend struct DefaultSingletonTraits<FrameAccessibility>; 75 }; 76 77 } // namespace content 78 79 #endif // CONTENT_BROWSER_FRAME_HOST_FRAME_ACCESSIBILITY_H_ 80