This reproduces a bug/limitation by UWP App-To-App communication when starting a client app and no result is returned by using:
Windows.System.Launcher.LaunchUriForResultsAsync(...)
API: https://docs.microsoft.com/de-de/windows/uwp/launch-resume/how-to-launch-an-app-for-results
Note: This also does not work using Xamarin.Forms UWP
The Master-App opens a Client App. When closing the Client App manually by ALT+F4 or Window Close Button the returned Result (ValueSet) from the Client App is NULL even if the Client App returns explicitly the ValueSet result in the Suspending event successfully using ProtocolForResultsOperation.ReportCompleted(values):
Suspending UWP API: https://docs.microsoft.com/en-us/windows/uwp/launch-resume/suspend-an-app
See also General API overview: https://slideplayer.com/slide/7501828/
Application.Current.Suspending += CurrentOnSuspending;
private void CurrentOnSuspending(object sender, SuspendingEventArgs e)
{
var deferral = e.SuspendingOperation.GetDeferral();
SuccessCallBack();
deferral.Complete();
}
private void SuccessCallBack()
{
if (protocolForResultsActivatedEventArgs != null)
{
var values = new ValueSet();
values.Add("Message", "This is message from app 2");
values.Add("IsUser", "true");
protocolForResultsActivatedEventArgs.ProtocolForResultsOperation.ReportCompleted(values);
}
}
