namespace WinUI.DI.FrameNavigate
{
    public partial class App : global::Microsoft.UI.Xaml.Markup.IXamlMetadataProvider
    {
        // ...
        private global::WinUI.DI.FrameNavigate.WinUI_DI_FrameNavigate_XamlTypeInfo.XamlMetaDataProvider _AppProvider { get; }

        public global::Microsoft.UI.Xaml.Markup.IXamlType GetXamlType(global::System.Type type)
        {
            return _AppProvider.GetXamlType(type);
        }
        // ...
    }
}
namespace WinUI.DI.FrameNavigate.WinUI_DI_FrameNavigate_XamlTypeInfo
{
    public sealed class XamlMetaDataProvider : global::Microsoft.UI.Xaml.Markup.IXamlMetadataProvider
    {
        // ...
        private global::WinUI.DI.FrameNavigate.WinUI_DI_FrameNavigate_XamlTypeInfo.XamlTypeInfoProvider Provider { get; }

        public global::Microsoft.UI.Xaml.Markup.IXamlType GetXamlType(global::System.Type type)
        {
            return Provider.GetXamlType(type);
        }
    }

    internal partial class XamlTypeInfoProvider
    {
        // ...
        global::System.Type[] _typeTable = null;
        private void InitTypeTables()
        {
            // ...
            _typeTable[22] = typeof(global::WinUI.DI.FrameNavigate.Views.MainPage);
            // ...
        }

        private object Activate_22_MainPage() { return new global::WinUI.DI.FrameNavigate.Views.MainPage(); }

        private global::Microsoft.UI.Xaml.Markup.IXamlType CreateXamlType(int typeIndex)
        {
            // ...
            global::WinUI.DI.FrameNavigate.WinUI_DI_FrameNavigate_XamlTypeInfo.XamlSystemBaseType xamlType = null;
            global::System.Type type = _typeTable[typeIndex];
            switch (typeIndex)
            {
                // ...
                case 22:
                    userType = new global::WinUI.DI.FrameNavigate.WinUI_DI_FrameNavigate_XamlTypeInfo.XamlUserType(this, typeName, type, GetXamlTypeByName("Microsoft.UI.Xaml.Controls.Page"));
                    userType.Activator = Activate_22_MainPage;
                    userType.AddMemberName("ViewModel");
                    userType.SetIsLocalType();
                    xamlType = userType;
                    break;
                // ...
            }
            return xamlType;
        }
    }

    internal class XamlSystemBaseType : global::Microsoft.UI.Xaml.Markup.IXamlType
    {
        // ...
        public XamlSystemBaseType(string fullName, global::System.Type underlyingType)
        {
            // ...
        }

        public global::System.Type UnderlyingType { get; }
        // ...
    }
    
    internal delegate object Activator();
    // ...

    internal class XamlUserType : global::WinUI.DI.FrameNavigate.WinUI_DI_FrameNavigate_XamlTypeInfo.XamlSystemBaseType
        , global::Microsoft.UI.Xaml.Markup.IXamlType
    {
        public XamlUserType(global::WinUI.DI.FrameNavigate.WinUI_DI_FrameNavigate_XamlTypeInfo.XamlTypeInfoProvider provider, string fullName, global::System.Type fullType, global::Microsoft.UI.Xaml.Markup.IXamlType baseType)
            :base(fullName, fullType)
        {
            // ...
        }

        // ...
        override public object ActivateInstance()
        {
            return Activator(); 
        }
        // ...
        public Activator Activator { get; set; }
        // ...
    }
}

namespace WinUI.DI.FrameNavigate;
file class XamlMetadataProvider : IXamlMetadataProvider
{
    // ...
    // The wrapped provider, initialized in the constructor.
    private readonly IXamlMetadataProvider _appProvider;
    // The App's ServiceProvider.
    private IServiceProvider ServiceProvider { get; }

    private void RetargetUserTypeActivator(IXamlType? xamlType)
    {
        // ...
        // The implementation is equivalent to this.
        // xamlType.Activator = () => ServiceProvider.GetService(xamlType.UnderlyingType);
    }

    public IXamlType GetXamlType(Type type)
    {
        var xamlType = _appProvider.GetXamlType(type);
        RetargetUserTypeActivator(xamlType);
        return xamlType;
    }

    public IXamlType GetXamlType(string fullName)
    {
        var xamlType = _appProvider.GetXamlType(fullName);
        RetargetUserTypeActivator(xamlType);
        return xamlType;
    }

    public XmlnsDefinition[] GetXmlnsDefinitions() => _appProvider.GetXmlnsDefinitions();
    // ...
}

partial class App : IXamlMetadataProvider
{
    // ...
    // The custom provider.
    private IXamlMetadataProvider _AppUserProvider { get; }
    IXamlType IXamlMetadataProvider.GetXamlType(Type type) => _AppUserProvider.GetXamlType(type);
    IXamlType IXamlMetadataProvider.GetXamlType(string fullName) => _AppUserProvider.GetXamlType(fullName);
    // ...
}