public async void Run(IBackgroundTaskInstance taskInstance)
 {
     BackgroundTaskDeferral deferral = taskInstance.GetDeferral();
     try
     {
         WallpaperService service = new WallpaperService();
         Wallpaper wallpaper = await service.GetNewestWallpaperAsync(AppSetting.Area);
         if (wallpaper != null)
         {
             TileHelper.UpdatePrimaryTile(wallpaper);
         }
     }
     finally
     {
         deferral.Complete();
     }
 }
 private async Task UpdatePrimaryTile()
 {
     try
     {
         WallpaperService service = new WallpaperService();
         Wallpaper wallpaper = await service.GetNewestWallpaperAsync(AppSetting.Area);
         if (wallpaper != null)
         {
             TileHelper.UpdatePrimaryTile(wallpaper);
         }
     }
     catch
     {
         // ignored
     }
 }