static async Task CreateDialog(ContentDialog Dialog, bool awaitPreviousDialog)
{
if (ActiveDialog != null)
{
if (awaitPreviousDialog)
{
ActiveDialog.Hide();
}
else
{
switch (Info.Status)
{
case AsyncStatus.Started:
Info.Cancel();
break;
case AsyncStatus.Completed:
Info.Close();
break;
case AsyncStatus.Error:
break;
case AsyncStatus.Canceled:
break;
}
}
}
ActiveDialog = Dialog;
ActiveDialog.Closing += ActiveDialog_Closing;
Info = ActiveDialog.ShowAsync();
}
internal void CloseStreamOperation()
{
try
{
if (_asyncStreamOperation != null)
{
_asyncStreamOperation.Close();
}
}
catch { }
_asyncStreamOperation = null;
}
private void Done(IAsyncInfo info, AsyncStatus status, bool initial)
{
var error = default(Exception);
var result = default(TResult);
//
// Initial interactions with the IAsyncInfo object. Those could fail, which indicates
// a rogue implementation. Failure is just propagated out.
//
switch (status)
{
case AsyncStatus.Error:
error = info.ErrorCode;
if (error == null)
{
throw new InvalidOperationException("The asynchronous operation failed with a null error code.");
}
break;
case AsyncStatus.Canceled:
error = new OperationCanceledException();
break;
case AsyncStatus.Completed:
if (_getResult != null)
{
result = _getResult(info);
}
break;
default:
if (!initial)
{
throw new InvalidOperationException("The asynchronous operation completed unexpectedly.");
}
_onCompleted(info, (iai, s) => Done(iai, s, false));
return;
}
//
// Close as early as possible, before running continuations which could fail. In case of
// failure above, we don't close out the object in order to allow for debugging of the
// rogue implementation without losing state prematurely. Notice _getResults is merely
// an indirect call to the appropriate GetResults method, which is not supposed to throw.
// Instead, an Error status should be returned.
//
info.Close();
//
// Now we run the continuations, which could take a long time. Failure here is catastrophic
// and under control of the upstream subscriber.
//
if (error != null)
{
_subject.OnError(error);
}
else
{
if (_getResult != null)
{
_subject.OnNext(result);
}
_subject.OnCompleted();
}
}