How to handle AppWindow closing event before close window on MacOS?

[AllenMiaoFil]

Description

Hey Team,

I got a question about how I could handle closing event when we clicked close application button on MacOS,

I know there is a closing event when we click 'Close Window' on Windows like below code

#if WINDOWS

        builder.ConfigureLifecycleEvents(events =>
        {
            // Make sure to add "using Microsoft.Maui.LifecycleEvents;" in the top of the file
            events.AddWindows(windowsLifecycleBuilder =>
            {
                windowsLifecycleBuilder.OnWindowCreated(window =>
                {
                    window.ExtendsContentIntoTitleBar = false;
                    var handle = WinRT.Interop.WindowNative.GetWindowHandle(window);
                    var id = Microsoft.UI.Win32Interop.GetWindowIdFromWindow(handle);
                    var appWindow = Microsoft.UI.Windowing.AppWindow.GetFromWindowId(id);
                  
                    switch (appWindow.Presenter)
                    {
                        case Microsoft.UI.Windowing.OverlappedPresenter overlappedPresenter:
                           //disable the max button
                            overlappedPresenter.IsMaximizable = false;
                           break;
                    }

                   //When user execute the closing method, we can make the window do not close by   e.Cancel = true;.
                    appWindow.Closing += async (s, e) =>
                    {
                        e.Cancel = true;                      
                    };
               });         
            });
        });
#endif

Steps to Reproduce

No response

Link to public reproduction project repository

No response

Version with bug

7.0.101

Is this a regression from previous behavior?

Not sure, did not test other versions

Last version that worked well

Unknown/Other

Affected platforms

macOS

Affected platform versions

No response

Did you find any workaround?

No response

Relevant log output

No response

[PureWeen]

AFAIK there's not really a way to do this from Catalyst

You'll have to dip down into the AppKit layer and tie into windowshouldclose

https://developer.apple.com/documentation/appkit/nswindowdelegate/1419380-windowshouldclose
or
Tie into the NSWindow
https://developer.apple.com/forums/thread/713172