public async Task TestRenderUIElementAsync()
{
var taskSource = new TaskCompletionSource <object>();
await CoreApplication.MainView.CoreWindow.Dispatcher.RunAsync(
CoreDispatcherPriority.Normal, async() =>
{
try
{
var file = await _storageService.CreateOrGetFileAsync(TEST_FILE_PATH);
using (var stream = await file.OpenAsync(FileAccessMode.ReadWrite))
{
var uiElement = new SampleControl300();
RenderTargetBitmap res = await _graphicsService.RenderToStreamAsync(uiElement, stream, BitmapEncoder.PngEncoderId);
Assert.IsNotNull(res); // fails, because the UI element has to be added to the visual tree before
Assert.AreEqual(300, res.PixelHeight);
Assert.AreEqual(300, res.PixelWidth);
}
taskSource.SetResult(null);
}
catch (Exception e)
{
taskSource.SetException(e);
}
});
await taskSource.Task;
}