private async Task UpdateCaptionTracksAsync()
{
// can be called before the this._MediaPlayer is assigned, this is also
// called during MediaOpened which inits the caption track list
if (null == this._MediaPlayer)
return;
await this._MediaPlayer.Dispatcher.RunAsync(Windows.UI.Core.CoreDispatcherPriority.Normal, async () =>
{
if (ClosedCaptionType.CC608Instream == this._CaptionType)
{
this._MediaPlayer.AvailableCaptions.Clear();
this._MediaPlayer.SelectedCaption = null;
// MMPPF will add the "Off" option automatically when a caption track is selected
this._MediaPlayer.AvailableCaptions.Add(new Caption() { Id = "1", Description = "CC1" });
this._MediaPlayer.AvailableCaptions.Add(new Caption() { Id = "2", Description = "CC2" });
this._MediaPlayer.AvailableCaptions.Add(new Caption() { Id = "3", Description = "CC3" });
this._MediaPlayer.AvailableCaptions.Add(new Caption() { Id = "4", Description = "CC4" });
// raise event
if (null != this.AvailableCaptionsPopulated)
this.AvailableCaptionsPopulated(this, EventArgs.Empty);
}
else if(this._CaptionType == ClosedCaptionType.WebVTTSidecar)
{
try
{
if (this._Controller != null &&
this._Controller.IsValid &&
this._Controller.Playlist != null &&
this._Controller.Playlist.IsMaster)
{
this._WebVTTCaptions = new HLSWebVTTCaptions(this._MediaPlayer, this._Controller);
await this._WebVTTCaptions.UpdateCaptionOptionsAsync();
// raise event
if (null != this.AvailableCaptionsPopulated)
this.AvailableCaptionsPopulated(this, EventArgs.Empty);
}
}
catch { }
}
});
}
/// <summary>
/// Occurs just before the MMPPF MediaPlayer source is set, cancel any closed caption downloads for the current video.
/// </summary>
/// <param name="sender">MMPPF media player.</param>
/// <param name="e">Loading data.</param>
private void MediaPlayer_MediaLoading(object sender, MediaPlayerDeferrableEventArgs e)
{
if (null != this._WebVTTCaptions)
{
this._WebVTTCaptions.Cancel();
this._WebVTTCaptions = null;
}
}
/// <summary>
/// The selected closed caption has changed.
/// </summary>
/// <param name="sender">MMPPF media player.</param>
/// <param name="e">Selected closed caption data.</param>
private async void MediaPlayer_SelectedCaptionChanged(object sender, RoutedPropertyChangedEventArgs<Caption> e)
{
try
{
// only process for WebVTT captions
if (ClosedCaptionType.WebVTTSidecar != this._CaptionType)
return;
if (null != this._WebVTTCaptions)
{
this._WebVTTCaptions.Cancel();
this._WebVTTCaptions = null;
}
if (null != e.NewValue && this._Controller.IsValid)
{
this._WebVTTCaptions = new HLSWebVTTCaptions(this._MediaPlayer, _Controller);
await this._WebVTTCaptions.DownloadAllSegmentsAsync(e.NewValue.Id);
}
}
catch { }
}
/// <summary>
/// Occurs when the MediaElement has closed the media source audio or video.
/// </summary>
/// <param name="sender">MMPPF media player.</param>
/// <param name="e">Not used.</param>
private void MediaPlayer_MediaClosed(object sender, RoutedEventArgs e)
{
if (null != this._WebVTTCaptions)
{
this._WebVTTCaptions.Cancel();
this._WebVTTCaptions = null;
}
}
