/// <summary>
/// Gets and returns the current UWP XAML Application instance in a reference parameter.
/// If the current XAML Application instance has not been created for the process (is null),
/// a new <see cref="Microsoft.Toolkit.Win32.UI.XamlHost.XamlApplication" /> instance is created and returned.
/// </summary>
/// <returns>The instance of <seealso cref="XamlApplication"/></returns>
public static IXamlMetadataContainer GetOrCreateXamlMetadataContainer()
{
// Instantiation of the application object must occur before creating the DesktopWindowXamlSource instance.
// DesktopWindowXamlSource will create a generic Application object unable to load custom UWP XAML metadata.
if (_metadataContainer == null)
{
// Create a custom UWP XAML Application object that implements reflection-based XAML metadata probing.
try
{
var app = new XamlApplication();
app.MetadataProviders.AddRange(MetadataProviderDiscovery.DiscoverMetadataProviders());
return(app);
}
catch
{
_metadataContainer = WUX.Application.Current as IXamlMetadataContainer;
}
}
var xamlApplication = _metadataContainer as XamlApplication;
if (xamlApplication != null && xamlApplication.IsDisposed)
{
throw new ObjectDisposedException(typeof(XamlApplication).FullName);
}
return(_metadataContainer);
}
/// <summary>
/// Gets and returns the current UWP XAML Application instance in a reference parameter.
/// If the current XAML Application instance has not been created for the process (is null),
/// a new <see cref="Microsoft.Toolkit.Win32.UI.XamlHost.XamlApplication" /> instance is created and returned.
/// </summary>
internal static void GetOrCreateXamlApplicationInstance(ref Windows.UI.Xaml.Application application)
{
// Instantiation of the application object must occur before creating the DesktopWindowXamlSource instance.
// DesktopWindowXamlSource will create a generic Application object unable to load custom UWP XAML metadata.
if (application == null)
{
try
{
// Windows.UI.Xaml.Application.Current may throw if DXamlCore has not been initialized.
// Treat the exception as an uninitialized Windows.UI.Xaml.Application condition.
application = Windows.UI.Xaml.Application.Current;
}
catch
{
// Create a custom UWP XAML Application object that implements reflection-based XAML metadata probing.
application = new XamlApplication();
}
}
}
private static void RaiseApplicationCreated(XamlApplication application)
{
ApplicationCreated?.Invoke(application, new EventArgs());
}