// found in the LICENSE file.
//
// Given a starting render_process_id and main_render_frame_id, the
-// WebContentsTracker tracks RenderViewHost instance swapping during the
-// lifetime of a WebContents instance. This is used when mirroring tab video
-// and audio so that user navigations, crashes, etc., during a tab's lifetime
-// allow the capturing code to remain active on the current/latest RenderView.
-//
-// TODO(miu): In a soon upcoming change, the cross-site isolation migration of
-// this code will be completed such that the main RenderFrameHost is tracked
-// instead of the RenderViewHost.
+// WebContentsTracker tracks changes to the active RenderFrameHost tree during
+// the lifetime of a WebContents instance. This is used when mirroring tab
+// video and audio so that user navigations, crashes, iframes, etc., during a
+// tab's lifetime allow the capturing code to remain active on the
+// current/latest render frame tree.
//
// Threading issues: Start(), Stop() and the ChangeCallback are invoked on the
// same thread. This can be any thread, and the decision is locked-in by
namespace content {
+class RenderWidgetHost;
+
class CONTENT_EXPORT WebContentsTracker
: public base::RefCountedThreadSafe<WebContentsTracker>,
public WebContentsObserver {
public:
- WebContentsTracker();
+ // If |track_fullscreen_rwh| is true, the ChangeCallback will be run when a
+ // WebContents shows/destroys a fullscreen RenderWidgetHost view. If false,
+ // fullscreen events are ignored. Specify true for video tab capture and
+ // false for audio tab capture.
+ explicit WebContentsTracker(bool track_fullscreen_rwh);
- // Callback for whenever the target is swapped. The callback is also invoked
- // with both arguments set to MSG_ROUTING_NONE to indicate tracking will not
- // continue (i.e., the WebContents instance was not found or has been
- // destroyed).
- typedef base::Callback<void(int render_process_id, int render_view_id)>
- ChangeCallback;
+ // Callback to indicate a new RenderWidgetHost should be targeted for capture.
+ // This is also invoked with NULL to indicate tracking will not continue
+ // (i.e., the WebContents instance was not found or has been destroyed).
+ typedef base::Callback<void(RenderWidgetHost* rwh)> ChangeCallback;
// Start tracking. The last-known |render_process_id| and
- // |main_render_frame_id| are provided, and the given callback is invoked
- // asynchronously one or more times. The callback will be invoked on the same
+ // |main_render_frame_id| are provided, and |callback| will be run once to
+ // indicate the current capture target (this may occur during the invocation
+ // of Start(), or in the future). The callback will be invoked on the same
// thread calling Start().
virtual void Start(int render_process_id, int main_render_frame_id,
const ChangeCallback& callback);
// be invoked again.
virtual void Stop();
+ // Current target. This must only be called on the UI BrowserThread.
+ RenderWidgetHost* GetTargetRenderWidgetHost() const;
+
protected:
friend class base::RefCountedThreadSafe<WebContentsTracker>;
virtual ~WebContentsTracker();
private:
- // Reads the render_process_id/render_view_id from the current WebContents
- // instance and then invokes the callback.
- void OnWebContentsChangeEvent();
+ // Determine the target RenderWidgetHost and, if different from that last
+ // reported, runs the ChangeCallback on the appropriate thread. If
+ // |force_callback_run| is true, the ChangeCallback is run even if the
+ // RenderWidgetHost has not changed.
+ void OnPossibleTargetChange(bool force_callback_run);
- // Called on the thread that Start()/Stop() are called on, check whether the
- // callback is still valid and, if so, invoke it.
- void MaybeDoCallback(int render_process_id, int render_view_id);
+ // Called on the thread that Start()/Stop() are called on. Checks whether the
+ // callback is still valid and, if so, runs it.
+ void MaybeDoCallback(RenderWidgetHost* rwh);
// Look-up the current WebContents instance associated with the given
// |render_process_id| and |main_render_frame_id| and begin observing it.
- void LookUpAndObserveWebContents(int render_process_id,
- int main_render_frame_id);
-
- // WebContentsObserver overrides to react to events of interest.
- virtual void RenderViewReady() OVERRIDE;
- virtual void AboutToNavigateRenderView(RenderViewHost* render_view_host)
- OVERRIDE;
- virtual void DidNavigateMainFrame(const LoadCommittedDetails& details,
- const FrameNavigateParams& params) OVERRIDE;
+ void StartObservingWebContents(int render_process_id,
+ int main_render_frame_id);
+
+ // WebContentsObserver overrides: According to web_contents_observer.h, these
+ // two method overrides are all that is necessary to track the set of active
+ // RenderFrameHosts.
+ virtual void RenderFrameDeleted(RenderFrameHost* render_frame_host) OVERRIDE;
+ virtual void RenderFrameHostChanged(RenderFrameHost* old_host,
+ RenderFrameHost* new_host) OVERRIDE;
+
+ // WebContentsObserver override to notify the client that the capture target
+ // has been permanently lost.
virtual void WebContentsDestroyed() OVERRIDE;
+ // WebContentsObserver overrides to notify the client that the capture target
+ // may have changed due to a separate fullscreen widget shown/destroyed.
+ virtual void DidShowFullscreenWidget(int routing_id) OVERRIDE;
+ virtual void DidDestroyFullscreenWidget(int routing_id) OVERRIDE;
+
+ // If true, the client is interested in the showing/destruction of fullscreen
+ // RenderWidgetHosts.
+ const bool track_fullscreen_rwh_;
+
+ // MessageLoop corresponding to the thread that called Start().
scoped_refptr<base::MessageLoopProxy> message_loop_;
+
+ // Callback to run when the target RenderWidgetHost has changed.
ChangeCallback callback_;
+ // Pointer to the RenderWidgetHost provided in the last run of |callback_|.
+ // This is used to eliminate duplicate callback runs.
+ RenderWidgetHost* last_target_;
+
DISALLOW_COPY_AND_ASSIGN(WebContentsTracker);
};
projects / platform / framework / web / crosswalk.git / blobdiff