问题
I am testing the Background Example with the Scenario4 and it never calls to Run, I am following the steps and that's what I see:
1.- After calling
BackgroundTaskRegistration task = builder.Register();
The task has Trigger = null
Does it should be the trigger specified before in
builder.SetTrigger(trigger); ?
2.- In theory when I register a background task, it should appear in here EventViewer - BackgroundTaskInfrastructure but it doesn't, should appear here?
3.- To try to debug I Debug Location - Suspend the App but after more than 15 minutes it never arrives, should be simple as suspend and wait?
Also I added inside Run a notification:
var toastXML = ToastNotificationManager.GetTemplateContent(ToastTemplateType.ToastText01);
var toastTextElements = toastXML.GetElementsByTagName("text");
toastTextElements.First().AppendChild(toastXML.CreateTextNode("Hello World:"));
var toastNotification = new ToastNotification(toastXML);
toastNotification.ExpirationTime = DateTimeOffset.UtcNow.AddSeconds(30);
ToastNotificationManager.CreateToastNotifier().Show(toastNotification);
But it never appears. So is BackgroundTask with TimeTrigger working?
回答1:
In my case I have an await call in the Run method of the BackgroundTask. After watching the video https://channel9.msdn.com/Events/Windows/Developers-Guide-to-Windows-10-RTM/Background-Execution I learn that I have to call to:
var cost = BackgroundWorkCost.CurrentBackgroundWorkCost;
And get the
var deferral = taskInstance.GetDeferral();
And finally when my calls finish call to:
deferral.Complete();
With that now it calls always my task always finish, the only issue and I think that it is not allowed is that I cannot call to:
Launcher.LaunchUriAsync(new Uri(favorite.Uri, UriKind.Absolute));
might be the launcher is not allowed but the toast is now showed every 15 minutes.
来源：https://stackoverflow.com/questions/31807296/backgroundtask-uwp-windows-10-timetriggeredtask-example-registered-but-never-fir