chrome/browser/media/router/presentation_media_sinks_observer.cc

   1 // Copyright 2015 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 "chrome/browser/media/router/presentation_media_sinks_observer.h"
   6
   7 #include "chrome/browser/media/router/media_router.h"
   8 #include "chrome/browser/media/router/media_source.h"
   9 #include "content/public/browser/presentation_screen_availability_listener.h"
  10
  11 namespace media_router {
  12
  13 PresentationMediaSinksObserver::PresentationMediaSinksObserver(
  14     MediaRouter* router,
  15     content::PresentationScreenAvailabilityListener* listener,
  16     const MediaSource& source)
  17     : MediaSinksObserver(router, source),
  18       listener_(listener),
  19       previous_availablity_(UNKNOWN) {
  20   DCHECK(router);
  21   DCHECK(listener_);
  22   DCHECK(!source.Empty());
  23 }
  24
  25 PresentationMediaSinksObserver::~PresentationMediaSinksObserver() {
  26 }
  27
  28 void PresentationMediaSinksObserver::OnSinksReceived(
  29     const std::vector<MediaSink>& result) {
  30   Availability current_availability = result.empty() ? UNAVAILABLE : AVAILABLE;
  31
  32   DVLOG(1) << "PresentationMediaSinksObserver::OnSinksReceived: "
  33            << source().ToString() << " "
  34            << (result.empty() ? "unavailable" : "available");
  35
  36   // Don't send if new result is same as previous.
  37   if (previous_availablity_ != current_availability)
  38     listener_->OnScreenAvailabilityChanged(current_availability == AVAILABLE);
  39
  40   previous_availablity_ = current_availability;
  41 }
  42
  43 }  // namespace media_router