Proposed tweaks for FocusTrap

[DannyRichardsonWG]

Hi Chris,

I've got custom dialogs in my setup and was having trouble with the preview packages. These tweaks sorted it for me.

Null check on FocusTrap in OnAfterRenderAsync

• If using custom dialogs _focusTrap is not set but there's no null check on the render

Make FocusTrap field public so it can be used in custom dialogs

• Changing to public means we can add FocusTrap in custom dialogs if we want to (and the null ref check prevents errors if we don't)
• Renamed _focusTrap to FocusTrap and set the variable annotation as nullable

I was tempted to change

    private void AttemptFocus() 
        => _setFocus = FocusTrap != null;

But wasn't sure if there's a time before the first render when the @ref gets set that AttemptFocus might be called

Cheers,

Danny

[chrissainty]

This all looks good to me bar the small change around the FocusTrap field. 👍

[chrissainty]

If we're making this public I think it would be better to swap to a property. As it's now nullable, we can remove the default assignment as well. Could you also move this a few lines up so it's with the other properties?

Suggested change

	public FocusTrap? FocusTrap = default;
	public FocusTrap? FocusTrap { get; set; }

[DannyRichardsonWG]

Hi Chris,

Sure, changes are in now.