OVERVIEW AND CLOSEALL

Question

OVERVIEW AND CLOSEALL

Giorgio Sfiligoi 656

Environment: MAUI 10

In Android, pressing the Overview button calls OnSleep, that I use for some clear-house, such as uploading a file to cloud storage. The following snippet is a simulation:


    protected async override void OnSleep()
    {
        base.OnSleep();
        Debug.WriteLine("OnSleep");
        //(Shell.Current.CurrentPage as SecondMainPage)?.SetActInd(true); NON FUNZIONA
        await Task.Run(async () =>
        {
            await Task.Delay(5000);
            Debug.WriteLine("Completed");
        });
    }

If you immediately press 'Close All' after the Overview button, the system kills the process and the task does not complete.

I would like that Android awaits the task to complete anyway.

Noor Fatima 85 Reputation points

2026-04-25T09:32:12.18+00:00

This is expected behavior on Android. When the user presses “Close All,” the system may terminate the app process immediately, so asynchronous work in OnSleep is not guaranteed to complete.

For scenarios like file uploads, it’s generally safer to persist the operation state locally and resume it when the application restarts. This approach improves reliability and user experience, especially in real-world conditions where apps can be interrupted at any time.

Alternatively, using platform-supported background processing (where applicable) can help handle such tasks more consistently.

3 answers

Your answer

Noor Fatima 85 Reputation points

2026-04-25T09:32:12.18+00:00

This is expected behavior on Android. When the user presses “Close All,” the system may terminate the app process immediately, so asynchronous work in OnSleep is not guaranteed to complete.

For scenarios like file uploads, it’s generally safer to persist the operation state locally and resume it when the application restarts. This approach improves reliability and user experience, especially in real-world conditions where apps can be interrupted at any time.

Alternatively, using platform-supported background processing (where applicable) can help handle such tasks more consistently.

Answer 1

Android cannot be forced to wait for asynchronous work in OnSleep once the user presses Overview and then “Close all”. When the task switcher’s “Close all” is used, Android is explicitly allowed to kill the app’s process; any in-flight background work in OnSleep or other lifecycle callbacks can be terminated at any time. .NET MAUI cannot override this behavior.

Key points from the MAUI lifecycle:

OnSleep (and the mapped OnPause / OnStop events on Android) are notification points, not guaranteed execution windows. The OS may kill the app immediately afterward, especially when the user explicitly closes it.
The MAUI Window.Stopped event maps to Android OnStop, and the docs explicitly note: “There’s no guarantee that an app will resume from this state, because it may be terminated by the operating system.” This also implies no guarantee that long-running work will complete.

Because of this, long-running or critical operations such as file uploads should not rely on finishing inside OnSleep or similar callbacks. Instead, use patterns that tolerate interruption, for example:

Persist upload state locally (e.g., mark items as “pending upload”) and resume uploads next time the app starts (OnCreate / OnApplicationCreate or app startup logic).
Use a proper background mechanism (e.g., a platform background service or scheduled job) that can continue independently of the UI process, if the scenario requires it and the platform permits.

In summary, Android cannot be instructed to wait for the Task.Run in OnSleep to complete when the user closes the app via “Close all”. The app must be designed so that such work can be safely interrupted and resumed later.

References:

Answer 2

Deleted

This answer has been deleted due to a violation of our Code of Conduct. The answer was manually reported or identified through automated detection before action was taken. Please refer to our Code of Conduct for more information.

Comments have been turned off. Learn more

Answer 3

Nancy Vo (WICLOUD CORPORATION) 3,550 Microsoft External Staff Moderator

Hello @Giorgio Sfiligoi ,

Thanks for your question.

Even though you wrote it as async, the MAUI/Android system fires it and moves on, it does not wait for your task to complete. So the moment you presses "Close All", Android kills the process immediately, and your upload task is cut off with no chance to finish.

It's simply how Android lifecycle works. OnSleep() was not designed to run long-running tasks.

I recommend moving your work outside of the app process lifecycle, into an Android Foreground Service. Because a Foreground Service runs independently from your app process. Even if your app is killed, the service keeps running until the job is done.

While this is a non-Microsoft link, it’s official Android documentation and is safe to visit.

I hope this addresses your question. If this response was helpful, please consider following the guidance to provide feedback.

Giorgio Sfiligoi 656 Reputation points

2026-04-25T05:19:28.7766667+00:00

Granted (from the AI reply) that it's impossible with NET MAUI, I believe that the Android class WorkManager could solve my problem.

Can anybody indoctrinate me on how to use it in my MAUI project?

Nancy Vo (WICLOUD CORPORATION) 3,550 Microsoft External Staff Moderator

Hi @Giorgio Sfiligoi ,

WorkManager does not guarantee immediate execution. It runs when the system is ready and constraints are met. You can refer to following steps and code examples:

Install the Nuget Package.

dotnet add package Xamarin.AndroidX.Work.Runtime

While this is a non-Microsoft link, it’s official NuGet documentation and is safe to visit.

Create the Worker Class.

This is code example in file UploadWorker:

Platforms/Android/UploadWorker.cs

using Android.Content;
using AndroidX.Work;
using System.Diagnostics;

namespace YourMauiApp.Platforms.Android
{
    public class UploadWorker : Worker
    {
        public UploadWorker(Context context, WorkerParameters workerParams)
            : base(context, workerParams)
        {
        }

        public override Result DoWork()
        {
            try
            {
                Task.Delay(5000).GetAwaiter().GetResult();
                Debug.WriteLine("Upload Completed!");

                return Result.InvokeSuccess();
            }
            catch (Exception ex)
            {
                Debug.WriteLine($" Upload Failed: {ex.Message}");

                return Result.InvokeRetry();
            }
        }
    }
}

Schedule the Work from OnSleep().

App.xaml.cs

protected override void OnSleep()
{
    base.OnSleep();

#if ANDROID
    ScheduleUploadWork();
#endif
}

#if ANDROID
private void ScheduleUploadWork()
{
    var constraints = new AndroidX.Work.Constraints.Builder()
        .SetRequiredNetworkType(AndroidX.Work.NetworkType.Connected)
        .Build();

    var uploadWorkRequest = new AndroidX.Work.OneTimeWorkRequest.Builder(
            Java.Lang.Class.FromType(typeof(UploadWorker)))
        .SetConstraints(constraints)
        .Build();

    AndroidX.Work.WorkManager
        .GetInstance(Android.App.Application.Context)
        .Enqueue(uploadWorkRequest);

    Debug.WriteLine("Upload work scheduled!");
}
#endif

Hope this helps. Thanks for your time.

Nancy Vo (WICLOUD CORPORATION) 3,550 Reputation points Microsoft External Staff Moderator

2026-05-05T02:45:16.43+00:00

Hi @Giorgio Sfiligoi ,
If you're still interested or have any questions, feel free to reach out whenever it works best for you.

Share via

OVERVIEW AND CLOSEALL

3 answers

Your answer