1 // Copyright 2013 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_TREE_H_ 6 #define CONTENT_BROWSER_FRAME_HOST_FRAME_TREE_H_ 7 8 #include <string> 9 10 #include "base/callback.h" 11 #include "base/memory/scoped_ptr.h" 12 #include "content/browser/frame_host/frame_tree_node.h" 13 #include "content/common/content_export.h" 14 15 namespace content { 16 17 class FrameTreeNode; 18 class Navigator; 19 class RenderFrameHostDelegate; 20 class RenderProcessHost; 21 class RenderViewHostDelegate; 22 class RenderViewHostImpl; 23 class RenderFrameHostManager; 24 class RenderWidgetHostDelegate; 25 26 // Represents the frame tree for a page. With the exception of the main frame, 27 // all FrameTreeNodes will be created/deleted in response to frame attach and 28 // detach events in the DOM. 29 // 30 // The main frame's FrameTreeNode is special in that it is reused. This allows 31 // it to serve as an anchor for state that needs to persist across top-level 32 // page navigations. 33 // 34 // TODO(ajwong): Move NavigationController ownership to the main frame 35 // FrameTreeNode. Possibly expose access to it from here. 36 // 37 // TODO(ajwong): Currently this class only contains FrameTreeNodes for 38 // subframes if the --site-per-process flag is enabled. 39 // 40 // This object is only used on the UI thread. 41 class CONTENT_EXPORT FrameTree { 42 public: 43 // Each FrameTreeNode will default to using the given |navigator| for 44 // navigation tasks in the frame. 45 // A set of delegates are remembered here so that we can create 46 // RenderFrameHostManagers. 47 // TODO(creis): This set of delegates will change as we move things to 48 // Navigator. 49 FrameTree(Navigator* navigator, 50 RenderFrameHostDelegate* render_frame_delegate, 51 RenderViewHostDelegate* render_view_delegate, 52 RenderWidgetHostDelegate* render_widget_delegate, 53 RenderFrameHostManager::Delegate* manager_delegate); 54 ~FrameTree(); 55 56 // Returns the FrameTreeNode with the given |frame_tree_node_id|. 57 FrameTreeNode* FindByID(int64 frame_tree_node_id); 58 59 // Executes |on_node| on each node in the frame tree. If |on_node| returns 60 // false, terminates the iteration immediately. Returning false is useful 61 // if |on_node| is just doing a search over the tree. 62 void ForEach(const base::Callback<bool(FrameTreeNode*)>& on_node) const; 63 64 // After the FrameTree is created, or after SwapMainFrame() has been called, 65 // the root node does not yet have a frame id. This is allocated by the 66 // renderer and is published to the browser process on the first navigation 67 // after a swap. These two functions are used to set the root node's frame 68 // id. 69 // 70 // TODO(ajwong): Remove these once RenderFrameHost's routing id replaces 71 // frame_id. 72 bool IsFirstNavigationAfterSwap() const; 73 void OnFirstNavigationAfterSwap(int main_frame_id); 74 75 // Frame tree manipulation routines. 76 // TODO(creis): These should take in RenderFrameHost routing IDs. 77 RenderFrameHostImpl* AddFrame(int render_frame_host_id, 78 int64 parent_frame_tree_node_id, 79 int64 frame_id, 80 const std::string& frame_name); 81 void RemoveFrame(RenderFrameHostImpl* render_frame_host, 82 int64 parent_frame_id, 83 int64 frame_id); 84 void SetFrameUrl(int64 frame_id, const GURL& url); 85 86 // Resets the FrameTree and changes RenderFrameHost for the main frame. 87 // This destroys most of the frame tree but retains the root node so that 88 // navigation state may be kept on it between process swaps. Used to 89 // support bookkeeping for top-level navigations. 90 // 91 // If |main_frame| is NULL, reset tree to initially constructed state. 92 // 93 // TODO(ajwong): This function should not be given a |main_frame|. This is 94 // required currently because the RenderViewHost owns its main frame. When 95 // that relation is fixed, the FrameTree should be responsible for 96 // created/destroying the main frame on the swap. 97 void SwapMainFrame(RenderFrameHostImpl* main_frame); 98 99 // Convenience accessor for the main frame's RenderFrameHostImpl. 100 RenderFrameHostImpl* GetMainFrame() const; 101 102 // Allows a client to listen for frame removal. The listener should expect 103 // to receive the RenderViewHostImpl containing the frame and the renderer- 104 // specific frame ID of the removed frame. 105 // TODO(creis): These parameters will later change to be the RenderFrameHost. 106 void SetFrameRemoveListener( 107 const base::Callback<void(RenderViewHostImpl*, int64)>& on_frame_removed); 108 109 FrameTreeNode* root() const { return root_.get(); } 110 111 private: 112 // Returns the FrameTreeNode with the given renderer-specific |frame_id|. 113 // For internal use only. 114 // TODO(creis): Replace this with a version that takes in a routing ID. 115 FrameTreeNode* FindByFrameID(int64 frame_id); 116 117 scoped_ptr<FrameTreeNode> CreateNode(int64 frame_id, 118 const std::string& frame_name, 119 int render_frame_host_id, 120 FrameTreeNode* parent_node); 121 122 // These delegates are installed into all the RenderViewHosts and 123 // RenderFrameHosts that we create. 124 RenderFrameHostDelegate* render_frame_delegate_; 125 RenderViewHostDelegate* render_view_delegate_; 126 RenderWidgetHostDelegate* render_widget_delegate_; 127 RenderFrameHostManager::Delegate* manager_delegate_; 128 129 scoped_ptr<FrameTreeNode> root_; 130 131 base::Callback<void(RenderViewHostImpl*, int64)> on_frame_removed_; 132 133 DISALLOW_COPY_AND_ASSIGN(FrameTree); 134 }; 135 136 } // namespace content 137 138 #endif // CONTENT_BROWSER_FRAME_HOST_FRAME_TREE_H_ 139
