marketally.mopups/Mopups/Mopups.Maui/Platforms/Windows/Handler/PopupPageHandler.cs

using Microsoft.Maui.Handlers;
using Microsoft.Maui.Layouts;
using Microsoft.Maui.Platform;

namespace Mopups.Platforms.Windows
{
    public class PopupPageHandler : PageHandler
    {
        private Microsoft.UI.Xaml.SizeChangedEventHandler? _sizeChangedHandler;

        public PopupPageHandler()
        {
        }

        protected override void ConnectHandler(ContentPanel platformView)
        {
            base.ConnectHandler(platformView);

            _sizeChangedHandler = (_, e) =>
            {
                try
                {
                    VirtualView?.ComputeDesiredSize(e.NewSize.Width, e.NewSize.Height);
                }
                catch (InvalidOperationException) { }
            };
            PlatformView.SizeChanged += _sizeChangedHandler;
        }

        protected override void DisconnectHandler(ContentPanel platformView)
        {
            if (_sizeChangedHandler != null)
            {
                platformView.SizeChanged -= _sizeChangedHandler;
                _sizeChangedHandler = null;
            }
            base.DisconnectHandler(platformView);
        }

        protected override ContentPanel CreatePlatformView()
        {
            return new PopupPageRenderer(this);
        }
    }
}