frame_tree_node.h revision 1e9bf3e0803691d0a228da41fc608347b6db4340 
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_NODE_H_
6#define CONTENT_BROWSER_FRAME_HOST_FRAME_TREE_NODE_H_
7
8#include <string>
9
10#include "base/basictypes.h"
11#include "base/memory/scoped_ptr.h"
12#include "base/memory/scoped_vector.h"
13#include "content/common/content_export.h"
14#include "url/gurl.h"
15
16namespace content {
17
18class RenderFrameHostImpl;
19
20// When a page contains iframes, its renderer process maintains a tree structure
21// of those frames. We are mirroring this tree in the browser process. This
22// class represents a node in this tree and is a wrapper for all objects that
23// are frame-specific (as opposed to page-specific).
24class CONTENT_EXPORT FrameTreeNode {
25 public:
26  static const int64 kInvalidFrameId;
27
28  FrameTreeNode(int64 frame_id, const std::string& name,
29                scoped_ptr<RenderFrameHostImpl> render_frame_host);
30  ~FrameTreeNode();
31
32  void AddChild(scoped_ptr<FrameTreeNode> child);
33  void RemoveChild(int64 child_id);
34
35  // Transitional API allowing the RenderFrameHost of a FrameTreeNode
36  // representing the main frame to be provided by someone else. After
37  // this is called, the FrameTreeNode no longer owns its RenderFrameHost.
38  //
39  // This should only be used for the main frame (aka root) in a frame tree.
40  //
41  // TODO(ajwong): Remove this method once the main frame RenderFrameHostImpl is
42  // no longer owned by the RenderViewHostImpl.
43  void ResetForMainFrame(RenderFrameHostImpl* new_render_frame_host);
44
45  void set_frame_id(int64 frame_id) {
46    DCHECK_EQ(frame_id_, kInvalidFrameId);
47    frame_id_ = frame_id;
48  }
49
50  int64 frame_id() const {
51    return frame_id_;
52  }
53
54  const std::string& frame_name() const {
55    return frame_name_;
56  }
57
58  size_t child_count() const {
59    return children_.size();
60  }
61
62  FrameTreeNode* child_at(size_t index) const {
63    return children_[index];
64  }
65
66  const GURL& current_url() const {
67    return current_url_;
68  }
69
70  void set_current_url(const GURL& url) {
71    current_url_ = url;
72  }
73
74  RenderFrameHostImpl* render_frame_host() const {
75    return render_frame_host_;
76  }
77
78 private:
79  // The unique identifier for the frame in the page.
80  int64 frame_id_;
81
82  // The assigned name of the frame. This name can be empty, unlike the unique
83  // name generated internally in the DOM tree.
84  std::string frame_name_;
85
86  // The immediate children of this specific frame.
87  ScopedVector<FrameTreeNode> children_;
88
89  // When ResetForMainFrame() is called, this is set to false and the
90  // |render_frame_host_| below is not deleted on destruction.
91  //
92  // For the mainframe, the FrameTree does not own the |render_frame_host_|.
93  // This is a transitional wart because RenderViewHostManager does not yet
94  // have the bookkeeping logic to handle creating a pending RenderFrameHost
95  // along with a pending RenderViewHost. Thus, for the main frame, the
96  // RenderViewHost currently retains ownership and the FrameTreeNode should
97  // not delete it on destruction.
98  bool owns_render_frame_host_;
99
100  // The active RenderFrameHost for this frame. The FrameTreeNode does not
101  // always own this pointer.  See comments above |owns_render_frame_host_|.
102  // TODO(ajwong): Replace with RenderFrameHostManager.
103  RenderFrameHostImpl* render_frame_host_;
104
105  // Track the current frame's last committed URL, so we can estimate the
106  // process impact of out-of-process iframes.
107  // TODO(creis): Remove this when we can store subframe URLs in the
108  // NavigationController.
109  GURL current_url_;
110
111  DISALLOW_COPY_AND_ASSIGN(FrameTreeNode);
112};
113
114}  // namespace content
115
116#endif  // CONTENT_BROWSER_FRAME_HOST_FRAME_TREE_NODE_H_
117