prerender_observer.h revision ddb351dbec246cf1fab5ec20d2d5520909041de1 
1// Copyright (c) 2011 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 CHROME_BROWSER_PRERENDER_PRERENDER_OBSERVER_H_
6#define CHROME_BROWSER_PRERENDER_PRERENDER_OBSERVER_H_
7#pragma once
8
9#include <list>
10#include <vector>
11
12#include "base/memory/scoped_ptr.h"
13#include "base/time.h"
14#include "content/browser/tab_contents/tab_contents_observer.h"
15#include "googleurl/src/gurl.h"
16
17class PrerenderContents;
18class Profile;
19class TabContents;
20
21namespace prerender {
22
23class PrerenderManager;
24
25// PrerenderObserver is responsible for recording perceived pageload times
26// to compare PLT's with prerendering enabled and disabled.
27class PrerenderObserver : public TabContentsObserver {
28 public:
29  explicit PrerenderObserver(TabContents* tab_contents);
30  virtual ~PrerenderObserver();
31
32  // TabContentsObserver implementation.
33  virtual void ProvisionalChangeToMainFrameUrl(const GURL& url);
34  virtual bool OnMessageReceived(const IPC::Message& message);
35
36  // Message handler.
37  void OnDidStartProvisionalLoadForFrame(int64 frame_id,
38                                         bool main_frame,
39                                         const GURL& url);
40
41  virtual void DidStopLoading();
42
43 private:
44  // Retrieves the PrerenderManager, or NULL, if none was found.
45  PrerenderManager* MaybeGetPrerenderManager();
46
47  // Checks with the PrerenderManager if the specified URL has been preloaded,
48  // and if so, swap the RenderViewHost with the preload into this TabContents
49  // object.
50  bool MaybeUsePreloadedPage(const GURL& url);
51
52  // System time at which the current load was started for the purpose of
53  // the perceived page load time (PPLT).
54  base::TimeTicks pplt_load_start_;
55
56  DISALLOW_COPY_AND_ASSIGN(PrerenderObserver);
57};
58
59}  // prerender
60
61#endif  // CHROME_BROWSER_PRERENDER_PRERENDER_OBSERVER_H_
62