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.
5 #ifndef CONTENT_BROWSER_FRAME_HOST_FRAME_TREE_H_
6 #define CONTENT_BROWSER_FRAME_HOST_FRAME_TREE_H_
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"
19 class RenderFrameHostDelegate;
20 class RenderProcessHost;
21 class RenderViewHostDelegate;
22 class RenderViewHostImpl;
23 class RenderFrameHostManager;
24 class RenderWidgetHostDelegate;
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.
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
34 // TODO(ajwong): Move NavigationController ownership to the main frame
35 // FrameTreeNode. Possibly expose access to it from here.
37 // This object is only used on the UI thread.
38 class CONTENT_EXPORT FrameTree {
40 // Each FrameTreeNode will default to using the given |navigator| for
41 // navigation tasks in the frame.
42 // A set of delegates are remembered here so that we can create
43 // RenderFrameHostManagers.
44 // TODO(creis): This set of delegates will change as we move things to
46 FrameTree(Navigator* navigator,
47 RenderFrameHostDelegate* render_frame_delegate,
48 RenderViewHostDelegate* render_view_delegate,
49 RenderWidgetHostDelegate* render_widget_delegate,
50 RenderFrameHostManager::Delegate* manager_delegate);
53 // Returns the FrameTreeNode with the given |frame_tree_node_id|.
54 static FrameTreeNode* GloballyFindByID(int64 frame_tree_node_id);
56 FrameTreeNode* root() const { return root_.get(); }
58 // Returns the FrameTreeNode with the given |frame_tree_node_id| if it is part
60 FrameTreeNode* FindByID(int64 frame_tree_node_id);
62 // Returns the FrameTreeNode with the given renderer-specific |routing_id|.
63 FrameTreeNode* FindByRoutingID(int routing_id, int process_id);
65 // Executes |on_node| on each node in the frame tree. If |on_node| returns
66 // false, terminates the iteration immediately. Returning false is useful
67 // if |on_node| is just doing a search over the tree. The iteration proceeds
68 // top-down and visits a node before adding its children to the queue, making
69 // it safe to remove children during the callback.
70 void ForEach(const base::Callback<bool(FrameTreeNode*)>& on_node) const;
72 // Frame tree manipulation routines.
73 RenderFrameHostImpl* AddFrame(FrameTreeNode* parent,
76 const std::string& frame_name);
77 void RemoveFrame(FrameTreeNode* child);
79 // This method walks the entire frame tree and creates a RenderFrameProxyHost
80 // for the given |site_instance| in each node except the |source| one --
81 // the source will have a RenderFrameHost. It assumes that no frame tree
82 // nodes already have RenderFrameProxyHost for the given |site_instance|.
83 void CreateProxiesForSiteInstance(
84 FrameTreeNode* source,
85 SiteInstance* site_instance);
87 // Clears process specific-state after a main frame process swap.
88 // This destroys most of the frame tree but retains the root node so that
89 // navigation state may be kept on it between process swaps. Used to
90 // support bookkeeping for top-level navigations.
91 // TODO(creis): Look into how we can remove the need for this method.
92 void ResetForMainFrameSwap();
94 // Update the frame tree after a process exits. Any nodes currently using the
95 // given |render_view_host| will lose all their children.
96 // TODO(creis): This should take a RenderProcessHost once RenderFrameHost
97 // knows its process. Until then, we would just be asking the RenderViewHost
98 // for its process, so we'll skip that step.
99 void RenderProcessGone(RenderViewHost* render_view_host);
101 // Convenience accessor for the main frame's RenderFrameHostImpl.
102 RenderFrameHostImpl* GetMainFrame() const;
104 // Returns the focused frame.
105 FrameTreeNode* GetFocusedFrame();
107 // Sets the focused frame.
108 void SetFocusedFrame(FrameTreeNode* node);
110 // Allows a client to listen for frame removal. The listener should expect
111 // to receive the RenderViewHostImpl containing the frame and the renderer-
112 // specific frame routing ID of the removed frame.
113 void SetFrameRemoveListener(
114 const base::Callback<void(RenderFrameHost*)>& on_frame_removed);
116 // Creates a RenderViewHost for a new RenderFrameHost in the given
117 // |site_instance|. The RenderViewHost will have its Shutdown method called
118 // when all of the RenderFrameHosts using it are deleted.
119 RenderViewHostImpl* CreateRenderViewHost(SiteInstance* site_instance,
121 int main_frame_routing_id,
125 // Returns the existing RenderViewHost for a new RenderFrameHost.
126 // There should always be such a RenderViewHost, because the main frame
127 // RenderFrameHost for each SiteInstance should be created before subframes.
128 RenderViewHostImpl* GetRenderViewHost(SiteInstance* site_instance);
130 // Keeps track of which RenderFrameHosts are using each RenderViewHost. When
131 // the number drops to zero, we call Shutdown on the RenderViewHost.
132 void RegisterRenderFrameHost(RenderFrameHostImpl* render_frame_host);
133 void UnregisterRenderFrameHost(RenderFrameHostImpl* render_frame_host);
136 typedef base::hash_map<int, RenderViewHostImpl*> RenderViewHostMap;
137 typedef std::multimap<int, RenderViewHostImpl*> RenderViewHostMultiMap;
139 // A variation to the public ForEach method with a difference that the subtree
140 // starting at |skip_this_subtree| will not be recursed into.
141 void ForEach(const base::Callback<bool(FrameTreeNode*)>& on_node,
142 FrameTreeNode* skip_this_subtree) const;
144 // These delegates are installed into all the RenderViewHosts and
145 // RenderFrameHosts that we create.
146 RenderFrameHostDelegate* render_frame_delegate_;
147 RenderViewHostDelegate* render_view_delegate_;
148 RenderWidgetHostDelegate* render_widget_delegate_;
149 RenderFrameHostManager::Delegate* manager_delegate_;
151 // Map of SiteInstance ID to a RenderViewHost. This allows us to look up the
152 // RenderViewHost for a given SiteInstance when creating RenderFrameHosts.
153 // Combined with the refcount on RenderViewHost, this allows us to call
154 // Shutdown on the RenderViewHost and remove it from the map when no more
155 // RenderFrameHosts are using it.
157 // Must be declared before |root_| so that it is deleted afterward. Otherwise
158 // the map will be cleared before we delete the RenderFrameHosts in the tree.
159 RenderViewHostMap render_view_host_map_;
161 // Map of SiteInstance ID to RenderViewHosts that are pending shutdown. The
162 // renderers of these RVH are currently executing the unload event in
163 // background. When the SwapOutACK is received, they will be deleted. In the
164 // meantime, they are kept in this map, as they should not be reused (part of
165 // their state is already gone away).
166 RenderViewHostMultiMap render_view_host_pending_shutdown_map_;
168 scoped_ptr<FrameTreeNode> root_;
170 int64 focused_frame_tree_node_id_;
172 base::Callback<void(RenderFrameHost*)> on_frame_removed_;
174 DISALLOW_COPY_AND_ASSIGN(FrameTree);
177 } // namespace content
179 #endif // CONTENT_BROWSER_FRAME_HOST_FRAME_TREE_H_