/// <summary>
/// Raised when playlist changes to a new track
/// </summary>
/// <param name="sender"></param>
/// <param name="args"></param>
void PlaybackList_CurrentItemChanged(MediaPlaybackList sender, CurrentMediaPlaybackItemChangedEventArgs args)
{
//Uri s = GetCurrentTrackId();
// Get the new item
var item = args.NewItem;
Debug.WriteLine("PlaybackList_CurrentItemChanged: " + (item == null ? "null" : Convert.ToString(GetTrackId(item))));
// Update the system view
UpdateUVCOnNewTrack(item);
// Get the current track
Uri currentTrackId = null;
if (item != null)
{
string trackIdKey = item.Source.CustomProperties[TrackIdKey].ToString();
currentTrackId = new Uri(trackIdKey);
}
ApplicationSettingsHelper.SaveSettingsValue(ApplicationSettingsConstants.TrackId, currentTrackId == null ? null : currentTrackId.ToString());
MessageService.SendMessageToForeground(new TrackChangedMessage(currentTrackId));
}
/// <summary>
/// Handles background task cancellation. Task cancellation happens due to:
/// 1. Another Media app comes into foreground and starts playing music
/// 2. Resource pressure. Your task is consuming more CPU and memory than allowed.
/// In either case, save state so that if foreground app resumes it can know where to start.
/// </summary>
private void OnCanceled(IBackgroundTaskInstance sender, BackgroundTaskCancellationReason reason)
{
// You get some time here to save your state before process and resources are reclaimed
Debug.WriteLine("MyBackgroundAudioTask " + sender.Task.TaskId + " Cancel Requested...");
try
{
// immediately set not running
backgroundTaskStarted.Reset();
// save state
ApplicationSettingsHelper.SaveSettingsValue(ApplicationSettingsConstants.TrackId, GetCurrentTrackId() == null ? null : GetCurrentTrackId().ToString());
ApplicationSettingsHelper.SaveSettingsValue(ApplicationSettingsConstants.Position, BackgroundMediaPlayer.Current.Position.ToString());
ApplicationSettingsHelper.SaveSettingsValue(ApplicationSettingsConstants.BackgroundTaskState, BackgroundTaskState.Canceled.ToString());
ApplicationSettingsHelper.SaveSettingsValue(ApplicationSettingsConstants.AppState, Enum.GetName(typeof(AppState), foregroundAppState));
// unsubscribe from list changes
if (playbackList != null)
{
playbackList.CurrentItemChanged -= PlaybackList_CurrentItemChanged;
playbackList = null;
}
// unsubscribe event handlers
BackgroundMediaPlayer.MessageReceivedFromForeground -= BackgroundMediaPlayer_MessageReceivedFromForeground;
smtc.ButtonPressed -= smtc_ButtonPressed;
smtc.PropertyChanged -= smtc_PropertyChanged;
BackgroundMediaPlayer.Shutdown(); // shutdown media pipeline
}
catch (Exception ex)
{
Debug.WriteLine(ex.ToString());
}
deferral.Complete(); // signals task completion.
Debug.WriteLine("MyBackgroundAudioTask Cancel complete...");
}
/// <summary>
/// Fires when a message is recieved from the foreground app
/// </summary>
/// <param name="sender"></param>
/// <param name="e"></param>
void BackgroundMediaPlayer_MessageReceivedFromForeground(object sender, MediaPlayerDataReceivedEventArgs e)
{
foreach (string key in e.Data.Keys)
{
switch (key.ToLower())
{
case Constants.AppSuspended:
Debug.WriteLine("App suspending"); // App is suspended, you can save your task state at this point
foregroundAppState = ForegroundAppStatus.Suspended;
ApplicationSettingsHelper.SaveSettingsValue(Constants.CurrentTrack, Playlist.CurrentTrackName);
break;
case Constants.AppResumed:
Debug.WriteLine("App resuming"); // App is resumed, now subscribe to message channel
foregroundAppState = ForegroundAppStatus.Active;
break;
case Constants.StartPlayback: //Foreground App process has signalled that it is ready for playback
Debug.WriteLine("Starting Playback");
StartPlayback();
break;
}
}
}
/// <summary>
/// Start playlist and change UVC state
/// </summary>
private void StartPlayback()
{
try
{
//If the task was cancelled we would have saved the current track and its position. We will try playback from there
var currenttrackname = ApplicationSettingsHelper.ReadResetSettingsValue(Constants.CurrentTrack);
Debug.WriteLine("Start Playback! || TrackName: " + Playlist.CurrentTrackName.ToString());
Playlist.StartSelectedStream((string)currenttrackname);
if (Playlist.CurrentTrackName == "128")
{
currentTitle = "Vocaloid Radio 128 kbps";
}
else
{
currentTitle = "Vocaloid Radio 192 kbps";
}
UpdateUVCOnNewTrack();
BackgroundMediaPlayer.Current.Play();
}
catch (Exception ex)
{
Debug.WriteLine(ex.ToString());
}
}
/// <summary>
/// Raised when a message is recieved from the foreground app
/// </summary>
/// <param name="sender"></param>
/// <param name="e"></param>
void BackgroundMediaPlayer_MessageReceivedFromForeground(object sender, MediaPlayerDataReceivedEventArgs e)
{
AppSuspendedMessage appSuspendedMessage;
if (MessageService.TryParseMessage(e.Data, out appSuspendedMessage))
{
Debug.WriteLine("App suspending"); // App is suspended, you can save your task state at this point
foregroundAppState = AppState.Suspended;
var currentTrackId = GetCurrentTrackId();
ApplicationSettingsHelper.SaveSettingsValue(ApplicationSettingsConstants.TrackId, currentTrackId == null ? null : currentTrackId.ToString());
return;
}
AppResumedMessage appResumedMessage;
if (MessageService.TryParseMessage(e.Data, out appResumedMessage))
{
Debug.WriteLine("App resuming"); // App is resumed, now subscribe to message channel
foregroundAppState = AppState.Active;
return;
}
StartPlaybackMessage startPlaybackMessage;
if (MessageService.TryParseMessage(e.Data, out startPlaybackMessage))
{
//Foreground App process has signalled that it is ready for playback
Debug.WriteLine("Starting Playback");
StartPlayback();
return;
}
SkipNextMessage skipNextMessage;
if (MessageService.TryParseMessage(e.Data, out skipNextMessage))
{
// User has chosen to skip track from app context.
Debug.WriteLine("Skipping to next");
SkipToNext();
return;
}
SkipPreviousMessage skipPreviousMessage;
if (MessageService.TryParseMessage(e.Data, out skipPreviousMessage))
{
// User has chosen to skip track from app context.
Debug.WriteLine("Skipping to previous");
SkipToPrevious();
return;
}
TrackChangedMessage trackChangedMessage;
if (MessageService.TryParseMessage(e.Data, out trackChangedMessage))
{
var index = playbackList.Items.ToList().FindIndex(i => (Uri)i.Source.CustomProperties[TrackIdKey] == trackChangedMessage.TrackId);
Debug.WriteLine("Skipping to track " + index);
smtc.PlaybackStatus = MediaPlaybackStatus.Changing;
playbackList.MoveTo((uint)index);
return;
}
UpdatePlaylistMessage updatePlaylistMessage;
if (MessageService.TryParseMessage(e.Data, out updatePlaylistMessage))
{
CreatePlaybackList(updatePlaylistMessage.Songs);
return;
}
}
/// <summary>
/// Start playlist and change UVC state
/// </summary>
private void StartPlayback()
{
try
{
// If playback was already started once we can just resume playing.
if (!playbackStartedPreviously)
{
playbackStartedPreviously = true;
// If the task was cancelled we would have saved the current track and its position. We will try playback from there.
var currentTrackId = ApplicationSettingsHelper.ReadResetSettingsValue(ApplicationSettingsConstants.TrackId);
var currentTrackPosition = ApplicationSettingsHelper.ReadResetSettingsValue(ApplicationSettingsConstants.Position);
if (currentTrackId != null)
{
// Find the index of the item by name
var index = playbackList.Items.ToList().FindIndex(item =>
GetTrackId(item).ToString() == (string)currentTrackId);
if (currentTrackPosition == null)
{
// Play from start if we dont have position
Debug.WriteLine("StartPlayback: Switching to track " + index);
playbackList.MoveTo((uint)index);
// Begin playing
BackgroundMediaPlayer.Current.Play();
}
else
{
// Play from exact position otherwise
TypedEventHandler <MediaPlaybackList, CurrentMediaPlaybackItemChangedEventArgs> handler = null;
handler = (MediaPlaybackList list, CurrentMediaPlaybackItemChangedEventArgs args) =>
{
if (args.NewItem == playbackList.Items[index])
{
// Unsubscribe because this only had to run once for this item
playbackList.CurrentItemChanged -= handler;
// Set position
var position = TimeSpan.Parse((string)currentTrackPosition);
Debug.WriteLine("StartPlayback: Setting Position " + position);
BackgroundMediaPlayer.Current.Position = position;
// Begin playing
BackgroundMediaPlayer.Current.Play();
}
};
playbackList.CurrentItemChanged += handler;
// Switch to the track which will trigger an item changed event
Debug.WriteLine("StartPlayback: Switching to track " + index);
playbackList.MoveTo((uint)index);
}
}
else
{
// Begin playing
BackgroundMediaPlayer.Current.Play();
}
}
else
{
// Begin playing
BackgroundMediaPlayer.Current.Play();
}
}
catch (Exception ex)
{
Debug.WriteLine(ex.ToString());
}
}
/// <summary>
/// Raised when a message is recieved from the foreground app
/// </summary>
/// <param name="sender"></param>
/// <param name="e"></param>
private async void BackgroundMediaPlayer_MessageReceivedFromForeground(object sender, MediaPlayerDataReceivedEventArgs e)
{
AppSuspendedMessage appSuspendedMessage;
if (MessageService.TryParseMessage(e.Data, out appSuspendedMessage))
{
Debug.WriteLine("App suspending"); // App is suspended, you can save your task state at this point
foregroundAppState = AppState.Suspended;
ApplicationSettingsHelper.SaveSettingsValue(ApplicationSettingsConstants.TrackId, CurrentMix == null ? 0 : CurrentMix.InternalID);
return;
}
AppResumedMessage appResumedMessage;
if (MessageService.TryParseMessage(e.Data, out appResumedMessage))
{
Debug.WriteLine("App resuming"); // App is resumed, now subscribe to message channel
foregroundAppState = AppState.Active;
return;
}
StartPlaybackMessage startPlaybackMessage;
if (MessageService.TryParseMessage(e.Data, out startPlaybackMessage))
{
//Foreground App process has signalled that it is ready for playback
Debug.WriteLine("Starting Playback");
await StartPlayback();
}
SkipNextMessage skipNextMessage;
if (MessageService.TryParseMessage(e.Data, out skipNextMessage))
{
// User has chosen to skip track from app context.
Debug.WriteLine("Skipping to next");
await SkipToNext();
}
SkipPreviousMessage skipPreviousMessage;
if (MessageService.TryParseMessage(e.Data, out skipPreviousMessage))
{
// User has chosen to skip track from app context.
Debug.WriteLine("Skipping to previous");
await SkipToPrevious();
}
TrackChangedMessage trackChangedMessage;
if (MessageService.TryParseMessage(e.Data, out trackChangedMessage))
{
await UpdateOptions();
CurrentMix = Playlist.Single(m => m.InternalID == trackChangedMessage.InternalMixID);
Debug.WriteLine("Skipping to track " + trackChangedMessage.InternalMixID);
smtc.PlaybackStatus = MediaPlaybackStatus.Changing;
await PlayCurrentMix();
}
UpdatePlaylistMessage updatePlaylistMessage;
if (MessageService.TryParseMessage(e.Data, out updatePlaylistMessage))
{
try
{
while (true)
{
try
{
await UpdateOptions();
break;
}
catch
{
}
}
if (updatePlaylistMessage.SendUpdateMessage)
{
MessageService.SendMessageToForeground(new UpdateMediaPlayerInfoMessage(CurrentMix == null ? 0 : CurrentMix.InternalID));
}
}
catch
{
}
}
UpdateUVCOnNewTrack(CurrentMix);
}
