private async void NextImage(ThreadPoolTimer timer)
{
if (_firstTimer)
{
timer.Cancel();
_timer1 = null;
_firstTimer = false;
}
// get next image
var image = await _reader.GetImage();
if (image != null)
{
// we have to update UI in UI thread only
await CoreApplication.MainView.CoreWindow.Dispatcher.RunAsync(
CoreDispatcherPriority.Normal,
() => ShowImage(image)
);
}
if (_timer1 == null)
{
_timer1 = ThreadPoolTimer.CreatePeriodicTimer(NextImage, TimeSpan.FromSeconds(18));
}
// cleanup
BmpCache.Cleanup();
}
private void ShowImage(string imageUri)
{
// check cache
if (!BmpCache.Cache.TryGetValue(imageUri, out BmpCache cacheItem))
{
cacheItem = new BmpCache
{
Uri = imageUri,
LastShownUtc = DateTime.UtcNow,
Bitmap = new BitmapImage
{
UriSource = new Uri(imageUri, UriKind.Absolute)
}
};
BmpCache.Cache[cacheItem.Uri] = cacheItem;
}
// display image
cacheItem.LastShownUtc = DateTime.UtcNow;
splashImage.Source = cacheItem.Bitmap;
}