How to customize a RadioButton on iOS

Question

In my app I would like to make the text in my radio button all capital. I first tried to use the TextTransform="Uppercase", but that didn't work (maybe this is a MAUI bug). I then thought I would use a handler for RadioButton, but I can't figure out how to change the text.

In the following, the view.Content = line won't work because Content only has a getter, not a setter. So, how can I change the content?

Microsoft.Maui.Handlers.RadioButtonHandler.Mapper.AppendToMapping(
	"MyRadioButton",
	(handler, view) => {
		if(view.Content is string text) {
			view.Content = text.ToUpperInvariant();
		}
	}
);

I then tried to go use an effect. With that I can find the UIView for the radio button, but I don't know how to find the text or label in it.

protected override void OnAttached()
{
	var effect = Element.Effects.OfType<UppercaseRoutingEffect>().FirstOrDefault();
	if(effect != null && Control is UIKit.UIView view) {
		... what do I do with the view here?
	}
}

Answer 1

I figured out a solution, but it's a bit ugly. I wish that TextTransform just worked out of the box.

	protected override void OnAttached()
	{
		var effect = Element.Effects.OfType<UppercaseRoutingEffect>().FirstOrDefault();
		if(effect != null && Control is UIKit.UIView view) {
			foreach(var sub in FindViews(view, v => v is UIKit.UILabel)) {
				var label = (UIKit.UILabel)sub;
				label.Text = label.Text?.ToUpperInvariant() ?? label.Text;
			}
		}
	}

	private static IEnumerable<UIKit.UIView> FindViews(UIKit.UIView view, Func<UIKit.UIView, bool> checker)
	{
		List<UIKit.UIView> results = new();
		void RecurseView(UIKit.UIView view)
		{
			if(checker(view)) {
				results.Add(view);
			}

			foreach(var sub in view.Subviews) {
				RecurseView(sub);
			}
		}
		RecurseView(view);
		return results;
	}