BindingBase automationIdBinding = Binding.Create(static (Element element) => element.AutomationId); 
defaultGridClass.Setters.Add(new Setter { Property = Element.AutomationIdProperty, Value = automationIdBinding });

DataTrigger newDataTrigger = new DataTrigger(typeof(ProgressBar))
{
    Binding = Binding.Create(static (ListItemViewModel vm) => vm.State),
    Value = ListItemViewModel.InstallableState.Downloading,
};
newDataTrigger.Setters.Add(new Setter { Property = ProgressBar.IsVisibleProperty, Value = true });

 entry1.SetBinding(Entry.TextProperty, 
 	new MultiBinding 
 	{ 
 		Bindings = new Collection<BindingBase> 
 		{ 
 			Binding.Create(static (Entry entry) => entry.FontFamily, source: RelativeBindingSource.Self), 
 			Binding.Create(static (Entry entry) => entry.FontSize, source: RelativeBindingSource.Self), 
 			Binding.Create(static (Entry entry) => entry.FontAttributes, source: RelativeBindingSource.Self), 
 		},
 		Converter = new StringConcatenationConverter() 
 	});