private void SaveLists(object sender, SuspendingEventArgs e)
        {
            var deferral = e.SuspendingOperation.GetDeferral();
            if (IsMyBackgroundTaskRunning)
            {
                // Stop handling player events immediately
                RemoveMediaPlayerEventHandlers();

                // Tell the background task the foreground is suspended
                MessageService.SendMessageToBackground(new AppStateChangedMessage(AppState.Suspended));
            }

            // Persist that the foreground app is suspended
            ApplicationSettingsHelper.SaveSettingsValue(ApplicationSettingsConstants.AppState, AppState.Suspended.ToString());
            ShuffleList shuffleList = new ShuffleList(Albums.albumList.ToList());
            shuffleList.SaveShuffleList(shuffleList.GenerateNewList(ShuffleList.FAV_LIST_CAPACITY));
            ShuffleList.SaveFavouriteList(shuffleList.GenerateFavouriteList());
            deferral.Complete();
        }
        private async void WaitingBar_Loaded(object sender, RoutedEventArgs e)
        {
            if (IsInitialed)
            {
                var str = ApplicationSettingsHelper.ReadResetSettingsValue("NewCreated");
                if (str == null)
                {
                    HideBar(WaitingBar);
                    str = ApplicationSettingsHelper.ReadResetSettingsValue("NewAdded");
                    if (str != null)
                    {
                        MessageService.SendMessageToBackground(new RefreshFilesMessage());
                        Albums.notifyrefresh += Albums_notifyrefresh;
                        await Albums.Refresh();
                        SetOtherPages();
                        if (Albums.albumList.Count > 0)
                        {
                            MessageService.SendMessageToBackground(new UpdateFilesMessage(Albums.albumList.ToSongModelList()));
                        }
                    }
                    str = ApplicationSettingsHelper.ReadResetSettingsValue("NewDeleted");
                    if (str != null)
                    {
                        Albums.RestoreAlbums();
                    }
                    return;
                }
            }
            RefreshState v = RefreshState.Normal;
            v = Albums.RestoreAlbums();
            Albums.CopytoAlbumList();
            Albums.progresschanged += Albums_progresschanged;
            switch (v)
            {
                case RefreshState.NeedCreate: await Albums.FirstCreate(); break;
                case RefreshState.NeedRefresh: await Albums.Refresh(); break;
                case RefreshState.Normal: break;
            }
            HideBar(WaitingBar);
            ((Window.Current.Content as Frame).Content as MainPage).FinishCreate();
            IsInitialed = true;
            foreach (var task in BackgroundTaskRegistration.AllTasks)
            {
                if (task.Value.Name == nameof(BackgroundAudio))
                {
                    isMyBackgroundTaskRunning = true;
                    break;
                }
            }
            StartBackgroundAudioTask();
            Application.Current.Suspending += SaveLists;
            TimeSpan period = TimeSpan.FromSeconds(5);
#pragma warning disable CS4014 // 由于此调用不会等待,因此在调用完成前将继续执行当前方法
            SetOtherPages();
#pragma warning restore CS4014 // 由于此调用不会等待,因此在调用完成前将继续执行当前方法
            PeriodicTimer = ThreadPoolTimer.CreateTimer((source) =>
            {
                if (!IsShuffleListInitialed)
                {
                    ShuffleList shuffleList = new ShuffleList(Albums.albumList.ToList());
                    var list = shuffleList.GenerateNewList(ShuffleList.FAV_LIST_CAPACITY);
                    list = ShuffleList.ShuffleIt(list);
#pragma warning disable CS4014 // 由于此调用不会等待,因此在调用完成前将继续执行当前方法
                    Dispatcher.RunAsync(CoreDispatcherPriority.High,
async () =>
{
    ShuffleListResources.Source = list;
    await ShowShuffleArtwork(list);
    HideBar(FavWaitingBar);
});
#pragma warning restore CS4014 // 由于此调用不会等待,因此在调用完成前将继续执行当前方法
                }
            }, period);
        }