.net MAUI Android call StartActivityForResult synchronously and wait OnActivityResult is called

[joolduprat]

Hello,

from my application i need to create a new activity to an external app to retrieve a result in OnActivityResult .
It's working well with StartActivityForResult then OnActivityResult is raised after externalActivity finished to process... So caller code is already finished...

So i would like to call the parent method in my viewModel which execute the StartActivityForResult code in an async / await context to have a business code linear without using a callback in the OnActivityResult...

Actually

public class MyViewModel
{
public async OnCallExternalIntent()
{
androidService.CreateExternalIntent() => this method calls inside StartActivityForResult then running thread is leaving and StartActivityForResult is raised. It's working....
}
}

But I would like to execute the method CreateExternalIntent in an await context to retrieve StartActivityForResult like that
public class MyViewModel
{
public async OnCallExternalIntent()
{
var otherActivityResult = await androidService.CreateExternalIntent();
}
}

public Task CreateNewActivity()
{
StartActivityForResult(planeteMonetiqueIntent, transaction.InteropMessageId);
AutoResetEvent.WaitOne();
return Task.FromResult(_otherActivityResult);
}

protected override void OnActivityResult(int requestCode, Result resultCode, Android.Content.Intent intent)
{
    Bundle bundle = intent.Extras;
    _currentResult = GetDataFromBundle();
    AutoResetEvent.Set();
}

I did this process to synchronized with USB device to retrieve Arduino process and my caller code is working well with await...

I saw this topic https://stackoverflow.com/questions/6351555/synchronous-startactivityforresult-waiting-for-activity-to-complete

I cannot use
Instrumentation instrumentation = new Instrumentation();
instrumentation.AddMonitor(planeteMonetiqueIntentFilter, null, false);

instrumentation.StartActivitySync(planeteMonetiqueIntent);

this code raised an error, cannot execute this code in main thread....

I tired to explain my probleme as simple as I can...

THank you.

Julien

[joolduprat]

Use of autoREsetEvent at viewmodel level it is working