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 FrameTreeNode
* root() const { return root_
.get(); }
55 // Returns the FrameTreeNode with the given |frame_tree_node_id|.
56 FrameTreeNode
* FindByID(int64 frame_tree_node_id
);
58 // Returns the FrameTreeNode with the given renderer-specific |routing_id|.
59 FrameTreeNode
* FindByRoutingID(int routing_id
, int process_id
);
61 // Executes |on_node| on each node in the frame tree. If |on_node| returns
62 // false, terminates the iteration immediately. Returning false is useful
63 // if |on_node| is just doing a search over the tree. The iteration proceeds
64 // top-down and visits a node before adding its children to the queue, making
65 // it safe to remove children during the callback.
66 void ForEach(const base::Callback
<bool(FrameTreeNode
*)>& on_node
) const;
68 // Frame tree manipulation routines.
69 RenderFrameHostImpl
* AddFrame(FrameTreeNode
* parent
,
71 const std::string
& frame_name
);
72 void RemoveFrame(FrameTreeNode
* child
);
74 // Clears process specific-state after a main frame process swap.
75 // This destroys most of the frame tree but retains the root node so that
76 // navigation state may be kept on it between process swaps. Used to
77 // support bookkeeping for top-level navigations.
78 // TODO(creis): Look into how we can remove the need for this method.
79 void ResetForMainFrameSwap();
81 // Update the frame tree after a process exits. Any nodes currently using the
82 // given |render_view_host| will lose all their children.
83 // TODO(creis): This should take a RenderProcessHost once RenderFrameHost
84 // knows its process. Until then, we would just be asking the RenderViewHost
85 // for its process, so we'll skip that step.
86 void RenderProcessGone(RenderViewHost
* render_view_host
);
88 // Convenience accessor for the main frame's RenderFrameHostImpl.
89 RenderFrameHostImpl
* GetMainFrame() const;
91 // Returns the focused frame.
92 FrameTreeNode
* GetFocusedFrame();
94 // Sets the focused frame.
95 void SetFocusedFrame(FrameTreeNode
* node
);
97 // Allows a client to listen for frame removal. The listener should expect
98 // to receive the RenderViewHostImpl containing the frame and the renderer-
99 // specific frame routing ID of the removed frame.
100 // TODO(creis): These parameters will later change to be the RenderFrameHost.
101 void SetFrameRemoveListener(
102 const base::Callback
<void(RenderViewHostImpl
*, int)>& on_frame_removed
);
104 // Creates a RenderViewHost for a new main frame RenderFrameHost in the given
105 // |site_instance|. The RenderViewHost will have its Shutdown method called
106 // when all of the RenderFrameHosts using it are deleted.
107 RenderViewHostImpl
* CreateRenderViewHostForMainFrame(
108 SiteInstance
* site_instance
,
110 int main_frame_routing_id
,
114 // Returns the existing RenderViewHost for a new subframe RenderFrameHost.
115 // There should always be such a RenderViewHost, because the main frame
116 // RenderFrameHost for each SiteInstance should be created before subframes.
117 RenderViewHostImpl
* GetRenderViewHostForSubFrame(SiteInstance
* site_instance
);
119 // Keeps track of which RenderFrameHosts are using each RenderViewHost. When
120 // the number drops to zero, we call Shutdown on the RenderViewHost.
121 void RegisterRenderFrameHost(RenderFrameHostImpl
* render_frame_host
);
122 void UnregisterRenderFrameHost(RenderFrameHostImpl
* render_frame_host
);
125 typedef base::hash_map
<int, RenderViewHostImpl
*> RenderViewHostMap
;
126 typedef std::multimap
<int, RenderViewHostImpl
*> RenderViewHostMultiMap
;
128 // These delegates are installed into all the RenderViewHosts and
129 // RenderFrameHosts that we create.
130 RenderFrameHostDelegate
* render_frame_delegate_
;
131 RenderViewHostDelegate
* render_view_delegate_
;
132 RenderWidgetHostDelegate
* render_widget_delegate_
;
133 RenderFrameHostManager::Delegate
* manager_delegate_
;
135 // Map of SiteInstance ID to a RenderViewHost. This allows us to look up the
136 // RenderViewHost for a given SiteInstance when creating RenderFrameHosts.
137 // Combined with the refcount on RenderViewHost, this allows us to call
138 // Shutdown on the RenderViewHost and remove it from the map when no more
139 // RenderFrameHosts are using it.
141 // Must be declared before |root_| so that it is deleted afterward. Otherwise
142 // the map will be cleared before we delete the RenderFrameHosts in the tree.
143 RenderViewHostMap render_view_host_map_
;
145 // Map of SiteInstance ID to RenderViewHosts that are pending shutdown. The
146 // renderers of these RVH are currently executing the unload event in
147 // background. When the SwapOutACK is received, they will be deleted. In the
148 // meantime, they are kept in this map, as they should not be reused (part of
149 // their state is already gone away).
150 RenderViewHostMultiMap render_view_host_pending_shutdown_map_
;
152 scoped_ptr
<FrameTreeNode
> root_
;
154 int64 focused_frame_tree_node_id_
;
156 base::Callback
<void(RenderViewHostImpl
*, int)> on_frame_removed_
;
158 DISALLOW_COPY_AND_ASSIGN(FrameTree
);
161 } // namespace content
163 #endif // CONTENT_BROWSER_FRAME_HOST_FRAME_TREE_H_