UWP timer background task doesn't run

Question

Using the below references, I attempted to make a background task in a UWP app:

https://docs.microsoft.com/en-us/windows/uwp/launch-resume/create-and-register-a-background-task

https://docs.microsoft.com/en-us/windows/uwp/launch-resume/run-a-background-task-on-a-timer-

https://www.youtube.com/watch?v=H18HrUin46I

Everything works as shown in the YouTube video when forcing the background task to run in debug mode, but the debug/release version on the app will not kick off the 15 minute background task on it's own. Here's the code:

MainPage.xaml.cs

using TimerBG;

bool taskRegistered = false;

foreach (var task in BackgroundTaskRegistration.AllTasks)
{
    if (task.Value.Name == nameof(BG))
    {
        task.Value.Unregister(true);
    }
}
if(!taskRegistered)
{
    Setup();
}

public async static void Setup()
{
    BackgroundAccessStatus status = await BackgroundExecutionManager.RequestAccessAsync();

    var builder = new BackgroundTaskBuilder();
    builder.Name = nameof(BG);
    builder.TaskEntryPoint = typeof(BG).ToString();
    TimeTrigger trig = new TimeTrigger(15, false);
    builder.SetTrigger(trig);
    SystemCondition userCondition = new SystemCondition(SystemConditionType.UserNotPresent);
    builder.AddCondition(userCondition);
    builder.CancelOnConditionLoss = false;
    builder.Register();
}

BG.cs

using Windows.ApplicationModel.Background;
using Windows.Storage;

namespace TimerBG
{
    public sealed class BG : IBackgroundTask
    {
        BackgroundTaskDeferral _deferral;

        public async void Run(IBackgroundTaskInstance taskInstance)
        {
            _deferral = taskInstance.GetDeferral();

            StorageFolder storageFolder = ApplicationData.Current.LocalFolder;
            StorageFile sampleFile = await storageFolder.GetFileAsync("sample.txt");
            await FileIO.WriteTextAsync(sampleFile, DateTime.Now.Minute.ToString() + ":" + DateTime.Now.Second.ToString());

            _deferral.Complete();
        }
    }
}

The package manifest background tasks property is set to "Timer" with the Entry Point as "TimerBG.BG".

I just saw that based on this documentation (docs.microsoft.com/en-us/uwp/api/…), and am testing UserPresent now on the Release code. — detailCode
Okay, switched to condition to SystemConditionType.UserPresent. Running the app in debug with VS, the background task never fires and hits my break point. I created buttons to check to see if the task is registered, and it is. What am I missing? — detailCode

detailCode detailCode · Accepted Answer · 2017-03-16T19:34:29

Found the solution after reading the article:

https://docs.microsoft.com/en-us/windows/uwp/launch-resume/debug-a-background-task

Background tasks and Visual Studio package deployment

If an app that uses background tasks is deployed using Visual Studio, and the version (major and/or minor) specified in Manifest Designer is then updated, subsequently re-deploying the app with Visual Studio may cause the app’s background tasks to stall. This can be remedied as follows:

If you already deployed the app using Visual Studio and its background tasks are now stalled, reboot or log off/log in to get the app’s background tasks working again.

UWP timer background task doesn't run

1 Answers