Exemplo n.º 1
0
        /// <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
            {
                //save state
                ApplicationSettingsHelper.SaveSettingsValue(Constants.CurrentTrack, Playlist.CurrentTrackName);
                ApplicationSettingsHelper.SaveSettingsValue(Constants.Position, BackgroundMediaPlayer.Current.Position.ToString());
                ApplicationSettingsHelper.SaveSettingsValue(Constants.BackgroundTaskState, Constants.BackgroundTaskCancelled);
                ApplicationSettingsHelper.SaveSettingsValue(Constants.AppState, Enum.GetName(typeof(ForegroundAppStatus), foregroundAppState));
                backgroundtaskrunning = false;
                //unsubscribe event handlers
                systemmediatransportcontrol.ButtonPressed   -= systemmediatransportcontrol_ButtonPressed;
                systemmediatransportcontrol.PropertyChanged -= systemmediatransportcontrol_PropertyChanged;
                Playlist.TrackChanged -= playList_TrackChanged;

                //clear objects task cancellation can happen uninterrupted
                playlistManager.ClearPlaylist();
                playlistManager = null;
                BackgroundMediaPlayer.Shutdown(); // shutdown media pipeline
            }
            catch (Exception ex)
            {
                Debug.WriteLine(ex.ToString());
            }
            deferral.Complete(); // signals task completion.
            Debug.WriteLine("MyBackgroundAudioTask Cancel complete...");
        }
Exemplo n.º 2
0
        /// <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
            {
                //save state
                ApplicationSettingsHelper.SaveSettingsValue(Constants.CurrentTrack, Playlist.CurrentTrackName);
                ApplicationSettingsHelper.SaveSettingsValue(Constants.Position, BackgroundMediaPlayer.Current.Position.ToString());
                ApplicationSettingsHelper.SaveSettingsValue(Constants.BackgroundTaskState, Constants.BackgroundTaskCancelled);
                ApplicationSettingsHelper.SaveSettingsValue(Constants.AppState, Enum.GetName(typeof(ForegroundAppStatus), foregroundAppState));
                backgroundtaskrunning = false;
                //unsubscribe event handlers
                systemmediatransportcontrol.ButtonPressed -= systemmediatransportcontrol_ButtonPressed;
                systemmediatransportcontrol.PropertyChanged -= systemmediatransportcontrol_PropertyChanged;
                Playlist.TrackChanged -= playList_TrackChanged;

                //clear objects task cancellation can happen uninterrupted
                playlistManager.ClearPlaylist();
                playlistManager = null;
                BackgroundMediaPlayer.Shutdown(); // shutdown media pipeline
            }
            catch (Exception ex)
            {
                Debug.WriteLine(ex.ToString());
            }
            deferral.Complete(); // signals task completion.
            Debug.WriteLine("MyBackgroundAudioTask Cancel complete...");
        }