AppDomain.CurrentDomain.ProcessExit is not called on macOS (maccatalyst) in MAUI app

[MartyIX]

Description

I have tried to register the AppDomain.CurrentDomain.ProcessExit event in my MAUI app running on macOS (maccatalyst) but the event is not fired. However, when the same app is run on Windows, the event is fired.

Filed also as: dotnet/maui#11676, @rolfbjarne suggested that this might be a dotnet/runtime repo so I took the opportunity to file the issue here. I'm sorry if this is not correct place. Feel free to close the issue if it does not belong here.

Reproduction Steps

Modify a sample MAUI app as follows:

using System;

public partial class App : Application
{
    public App()
    {
        InitializeComponent();

        MainPage = new AppShell();

        AppDomain.CurrentDomain.ProcessExit += this.OnProcessExit; // Added line.
    }

    // This method is not called on macOS but it is called on Windows.
    private void OnProcessExit(object sender, EventArgs e)
    {
        throw new Exception("REACHED?");
    }
}

Expected behavior

I expect OnProcessExit to be called.

Actual behavior

OnProcessExit method is NOT called.

Interestingly though, in a standard .NET console app on macOS (i.e net7.0), CurrentDomain_ProcessExit is called:

public static class Program
{
    public static void Main(string[] args)
    {
        AppDomain.CurrentDomain.ProcessExit += CurrentDomain_ProcessExit;
    }

    private static void CurrentDomain_ProcessExit(object? sender, EventArgs e)
    {
        throw new NotImplementedException();
    }
}

So the issue seems to be MAUI specific.

Regression?

No response

Known Workarounds

I have not found any.

Configuration

macOS M1, .NET 7 (i.e. latest released version)

Other information

No response

[dotnet-issue-labeler]

I couldn't figure out the best area label to add to this issue. If you have write-permissions please help me learn by adding exactly one area label.

[ghost]

Tagging subscribers to 'os-maccatalyst': @steveisok, @akoeplinger
See info in area-owners.md if you want to be subscribed.

Issue Details

---

Description

I have tried to register the AppDomain.CurrentDomain.ProcessExit event in my MAUI app running on macOS (maccatalyst) but the event is not fired. However, when the same app is run on Windows, the event is fired.

Filed also as: dotnet/maui#11676, @rolfbjarne suggested that this might be a dotnet/runtime repo so I took the opportunity to file the issue here. I'm sorry if this is not correct place. Feel free to close the issue if it does not belong here.

Reproduction Steps

Modify a sample MAUI app as follows:

using System;

public partial class App : Application
{
    public App()
    {
        InitializeComponent();

        MainPage = new AppShell();

        AppDomain.CurrentDomain.ProcessExit += this.OnProcessExit; // Added line.
    }

    // This method is not called on macOS but it is called on Windows.
    private void OnProcessExit(object sender, EventArgs e)
    {
        throw new Exception("REACHED?");
    }
}

Expected behavior

I expect OnProcessExit to be called.

Actual behavior

OnProcessExit method is NOT called.

Interestingly though, in a standard .NET console app on macOS (i.e net7.0), CurrentDomain_ProcessExit is called:

public static class Program
{
    public static void Main(string[] args)
    {
        AppDomain.CurrentDomain.ProcessExit += CurrentDomain_ProcessExit;
    }

    private static void CurrentDomain_ProcessExit(object? sender, EventArgs e)
    {
        throw new NotImplementedException();
    }
}

So the issue seems to be MAUI specific.

Regression?

No response

Known Workarounds

I have not found any.

Configuration

macOS M1, .NET 7 (i.e. latest released version)

Other information

No response

Author:	MartyIX
Assignees:	-
Labels:	untriaged, area-VM-meta-mono, os-maccatalyst
Milestone:	-

[MartyIX]

@steveisok @akoeplinger Any progress on this one please? Anything I can help with potentially?

[steveisok]

@akoeplinger Please take a look at this when you have a moment.