content/browser/media/capture/web_contents_tracker.cc

   1 // Copyright (c) 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 #include "content/browser/media/capture/web_contents_tracker.h"
   6
   7 #include "base/message_loop/message_loop_proxy.h"
   8 #include "content/public/browser/browser_thread.h"
   9 #include "content/public/browser/render_frame_host.h"
  10 #include "content/public/browser/render_process_host.h"
  11 #include "content/public/browser/render_view_host.h"
  12 #include "content/public/browser/web_contents.h"
  13
  14 namespace content {
  15
  16 WebContentsTracker::WebContentsTracker() {}
  17
  18 WebContentsTracker::~WebContentsTracker() {
  19   DCHECK(!web_contents()) << "BUG: Still observering!";
  20 }
  21
  22 void WebContentsTracker::Start(int render_process_id, int main_render_frame_id,
  23                                const ChangeCallback& callback) {
  24   DCHECK(!message_loop_.get() || message_loop_->BelongsToCurrentThread());
  25
  26   message_loop_ = base::MessageLoopProxy::current();
  27   DCHECK(message_loop_.get());
  28   callback_ = callback;
  29
  30   BrowserThread::PostTask(
  31       BrowserThread::UI, FROM_HERE,
  32       base::Bind(&WebContentsTracker::LookUpAndObserveWebContents, this,
  33                  render_process_id, main_render_frame_id));
  34 }
  35
  36 void WebContentsTracker::Stop() {
  37   DCHECK(message_loop_->BelongsToCurrentThread());
  38
  39   callback_.Reset();
  40
  41   BrowserThread::PostTask(
  42       BrowserThread::UI, FROM_HERE,
  43       base::Bind(&WebContentsTracker::Observe, this,
  44                  static_cast<WebContents*>(NULL)));
  45 }
  46
  47 void WebContentsTracker::OnWebContentsChangeEvent() {
  48   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
  49
  50   WebContents* const wc = web_contents();
  51   RenderViewHost* const rvh = wc ? wc->GetRenderViewHost() : NULL;
  52   RenderProcessHost* const rph = rvh ? rvh->GetProcess() : NULL;
  53
  54   const int render_process_id = rph ? rph->GetID() : MSG_ROUTING_NONE;
  55   const int render_view_id = rvh ? rvh->GetRoutingID() : MSG_ROUTING_NONE;
  56
  57   message_loop_->PostTask(FROM_HERE,
  58       base::Bind(&WebContentsTracker::MaybeDoCallback, this,
  59                  render_process_id, render_view_id));
  60 }
  61
  62 void WebContentsTracker::MaybeDoCallback(int render_process_id,
  63                                          int render_view_id) {
  64   DCHECK(message_loop_->BelongsToCurrentThread());
  65
  66   if (!callback_.is_null())
  67     callback_.Run(render_process_id, render_view_id);
  68 }
  69
  70 void WebContentsTracker::LookUpAndObserveWebContents(int render_process_id,
  71                                                      int main_render_frame_id) {
  72   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
  73
  74   Observe(WebContents::FromRenderFrameHost(RenderFrameHost::FromID(
  75       render_process_id, main_render_frame_id)));
  76   DVLOG_IF(1, !web_contents())
  77       << "Could not find WebContents associated with main RenderFrameHost "
  78       << "referenced by render_process_id=" << render_process_id
  79       << ", routing_id=" << main_render_frame_id;
  80
  81   OnWebContentsChangeEvent();
  82 }
  83
  84 void WebContentsTracker::RenderViewReady() {
  85   OnWebContentsChangeEvent();
  86 }
  87
  88 void WebContentsTracker::AboutToNavigateRenderView(RenderViewHost* rvh) {
  89   OnWebContentsChangeEvent();
  90 }
  91
  92 void WebContentsTracker::DidNavigateMainFrame(
  93     const LoadCommittedDetails& details, const FrameNavigateParams& params) {
  94   OnWebContentsChangeEvent();
  95 }
  96
  97 void WebContentsTracker::WebContentsDestroyed() {
  98   OnWebContentsChangeEvent();
  99 }
 100
 101 }  // namespace content