IUIContentConfiguration.MakeContentView() result fails to cast to UIView

[Uncommon]

Apple platform

iOS

Framework version

net8.0-*

Affected platform version

.NET 8.0.100 18.0.8303

Description

The return type of IUIContentConfiguration.MakeContentView() is simply IUIContentView. By contrast, in Swift it is UIView & UIContentView (and similarly in Objective-C), so we're missing the idea that the return type is not just an object that conforms to UIContentView, but it's specifically a UIView. Attempting to cast the result of MakeContentView() to UIView fails, which is also incorrect. This makes the composability aspect of content configurations unusable in C#: you can't take one configuration's view and embed it inside another.

Steps to Reproduce

1. Attempt to cast the result of a MakeContentView() call to UIView.
2. The result is null, which is incorrect. The result is always a UIView.

Did you find any workaround?

I haven't tried it yet, but I could make a subclass of UIView that implements IUIContentView, and return that from my custom content configurations. I think that would get around the casting issue for those cases, but it would not help for when I want to embed a system content configuration inside a custom one.

Relevant log output

No response

[rolfbjarne]

I'm not sure this is possible to bind correctly in C# without some ugly workarounds, because it's not possible to express in C# that a return type is both of a specific type and implements an interface.

Something like this might be an option, where you get two variables:

interface IUIContentConfiguration {
	public void MakeContentView (out UIView view, out IUIContentView contentView)
	{
		// ...
	}
}

Depending on your use case, it might be possible to work around it by doing this:

using ObjCRuntime;

UIContentConfiguration conf = ...;
var view = conf.MakeContentView ();
var uiView = Runtime.GetNSObject<UIView> (view.Handle, false);

However, can you explain a bit more how you want to use the return value, that might give me more ideas on how to bind it? If possible with some actual code samples.

[Uncommon]

The goal is to use content configurations compositionally. For example, to take a standard cell content view such as from UIListContentConfiguration.ValueCellConfiguration and add an error/info message below it.

I tried out Runtime.GetNSObject and it does seem to work. Thanks!