public BackgroundAudioRun(Guid id)
{
_id = id;
_foregroundNotifier = new ForegroundNotifier(id);
_timer = new Timer(_ =>
{
var metadataHandler = _metadataHandler;
if (null == metadataHandler)
{
return;
}
metadataHandler.Refresh();
}, null, Timeout.InfiniteTimeSpan, Timeout.InfiniteTimeSpan);
_notificationQueue = new ValueSetWorkerQueue(vs =>
{
HandleNotification(vs);
return(TplTaskExtensions.CompletedTask);
});
_watchdogTimer = new Timer(
_ =>
{
Debug.WriteLine("BackgroundAudioRun watchdog");
var barks = 1;
try
{
var foregroundId = BackgroundSettings.ForegroundId;
if (!foregroundId.HasValue || _completionSource.Task.IsCompleted)
{
Interlocked.Exchange(ref _watchdogBarks, 0);
StopWatchdog();
return;
}
barks = Interlocked.Increment(ref _watchdogBarks);
if (barks > 3)
{
Debug.WriteLine("BackgroundAudioRun watchdog exiting");
_completionSource.TrySetCanceled();
Cancel();
return;
}
_foregroundNotifier.Notify(BackgroundNotificationType.Ping);
}
catch (Exception ex)
{
Debug.WriteLine("BackgroundAudioRun watchdog failed: " + ex.ExtendedMessage());
}
RequestWatchdog(TimeSpan.FromTicks(WatchdogTimeout.Ticks >> barks));
},
null, Timeout.InfiniteTimeSpan, Timeout.InfiniteTimeSpan);
}
Task Update()
{
Debug.WriteLine("SmtcMetadataHandler.Update()");
try
{
var smtc = _systemMediaTransportControls;
var position = _getPosition();
TimeSpan?nextEvent = null;
lock (_lock)
{
nextEvent = _metadataSink.Update(_state, position);
}
var title = GetTitle();
var artist = GetArtist();
if (title != _title || artist != _artist)
{
Debug.WriteLine("SmtcMetadataHandler.Update() set " + title);
_title = title;
_artist = artist;
smtc.DisplayUpdater.ClearAll();
smtc.DisplayUpdater.Type = MediaPlaybackType.Music;
var properties = smtc.DisplayUpdater.MusicProperties;
if (null != title)
{
properties.Title = title;
}
if (null != artist)
{
properties.Artist = artist;
}
smtc.DisplayUpdater.Update();
_notifier.Notify(BackgroundNotificationType.Track, title);
}
if (nextEvent.HasValue && nextEvent > position)
{
if (nextEvent.Value != _lastReport)
{
_lastReport = nextEvent.Value;
_reportNextEvent(_lastReport);
}
}
}
catch (Exception ex)
{
Debug.WriteLine("SmtcMetadataSink.Update() failed: " + ex.Message);
}
return(TplTaskExtensions.CompletedTask);
}
public async Task ExecuteAsync()
{
Debug.WriteLine("BackgroundAudioRun.ExecuteAsync()");
try
{
_systemMediaTransportControls = SystemMediaTransportControls.GetForCurrentView();
var smtc = _systemMediaTransportControls;
var isOk = false;
BackgroundMediaPlayer.MessageReceivedFromForeground += BackgroundMediaPlayerOnMessageReceivedFromForeground;
var mediaPlayer = BackgroundMediaPlayer.Current;
_metadataHandler = new MetadataHandler(_systemMediaTransportControls, _foregroundNotifier,
() => mediaPlayer.Position,
position => UpdateMediaPlayerEvents(mediaPlayer, position),
_cancellationTokenSource.Token);
try
{
mediaPlayer.CurrentStateChanged += OnCurrentStateChanged;
mediaPlayer.PlaybackMediaMarkerReached += OnPlaybackMediaMarkerReached;
BackgroundSettings.SetBackgroundId(_id);
isOk = true;
}
catch (Exception ex)
{
Debug.WriteLine("BackgroundAudioRun.ExecuteAsync() initialization failed: " + ex.ExtendedMessage());
}
MediaPlayerManager mediaPlayerManager = null;
if (isOk)
{
try
{
mediaPlayerManager = new MediaPlayerManager(mediaPlayer, _metadataHandler, _cancellationTokenSource.Token);
mediaPlayerManager.TrackChanged += MediaPlayerManagerOnTrackChanged;
mediaPlayerManager.Failed += MediaPlayerManagerOnFailed;
mediaPlayerManager.Ended += MediaPlayerManagerOnEnded;
_mediaPlayerManager = mediaPlayerManager;
smtc.ButtonPressed += SystemMediaTransportControlsOnButtonPressed;
smtc.PropertyChanged += SystemMediaTransportControlsOnPropertyChanged;
smtc.IsEnabled = true;
smtc.IsPauseEnabled = true;
smtc.IsPlayEnabled = true;
smtc.IsNextEnabled = true;
smtc.IsPreviousEnabled = true;
SyncNotification();
Debug.WriteLine("BackgroundAudioRun.ExecuteAsync() running");
await _completionSource.Task.ConfigureAwait(false);
}
catch (Exception ex)
{
Debug.WriteLine("BackgroundAudioRun.ExecuteAsync() playback failed: " + ex.ExtendedMessage());
}
}
Debug.WriteLine("BackgroundAudioRun.ExecuteAsync() done running");
BackgroundSettings.RemoveBackgroundId(_id);
try
{
_timer.Change(Timeout.InfiniteTimeSpan, Timeout.InfiniteTimeSpan);
}
catch (Exception)
{
// Guard against race with cleanup
}
_mediaPlayerManager = null;
smtc.PropertyChanged -= SystemMediaTransportControlsOnPropertyChanged;
smtc.ButtonPressed -= SystemMediaTransportControlsOnButtonPressed;
if (null != mediaPlayerManager)
{
mediaPlayerManager.TrackChanged -= MediaPlayerManagerOnTrackChanged;
mediaPlayerManager.Failed -= MediaPlayerManagerOnFailed;
mediaPlayerManager.Ended -= MediaPlayerManagerOnEnded;
await mediaPlayerManager.CloseAsync().ConfigureAwait(false);
mediaPlayerManager.Dispose();
}
if (_appId.HasValue)
{
_foregroundNotifier.Notify(BackgroundNotificationType.Stop);
}
mediaPlayer.CurrentStateChanged -= OnCurrentStateChanged;
mediaPlayer.PlaybackMediaMarkerReached -= OnPlaybackMediaMarkerReached;
BackgroundMediaPlayer.MessageReceivedFromForeground -= BackgroundMediaPlayerOnMessageReceivedFromForeground;
}
catch (Exception ex)
{
Debug.WriteLine("BackgroundAudioRun.ExecuteAsync() failed: " + ex.ExtendedMessage());
}
finally
{
Debug.WriteLine("BackgroundAudioRun.ExecuteAsync() completed");
}
}
public BackgroundAudioRun(Guid id)
{
_id = id;
_foregroundNotifier = new ForegroundNotifier(id);
_timer = new Timer(_ =>
{
var metadataHandler = _metadataHandler;
if (null == metadataHandler)
return;
metadataHandler.Refresh();
}, null, Timeout.InfiniteTimeSpan, Timeout.InfiniteTimeSpan);
_notificationQueue = new ValueSetWorkerQueue(vs =>
{
HandleNotification(vs);
return TplTaskExtensions.CompletedTask;
});
_watchdogTimer = new Timer(
_ =>
{
Debug.WriteLine("BackgroundAudioRun watchdog");
var barks = 1;
try
{
var foregroundId = BackgroundSettings.ForegroundId;
if (!foregroundId.HasValue || _completionSource.Task.IsCompleted)
{
Interlocked.Exchange(ref _watchdogBarks, 0);
StopWatchdog();
return;
}
barks = Interlocked.Increment(ref _watchdogBarks);
if (barks > 3)
{
Debug.WriteLine("BackgroundAudioRun watchdog exiting");
_completionSource.TrySetCanceled();
Cancel();
return;
}
_foregroundNotifier.Notify(BackgroundNotificationType.Ping);
}
catch (Exception ex)
{
Debug.WriteLine("BackgroundAudioRun watchdog failed: " + ex.ExtendedMessage());
}
RequestWatchdog(TimeSpan.FromTicks(WatchdogTimeout.Ticks >> barks));
},
null, Timeout.InfiniteTimeSpan, Timeout.InfiniteTimeSpan);
}