Unity 6.3 alternative approach

[FrantisekHolubec]

Hi, I saw your approach to Unity 6.3 new toolbar
And I just wanted to share my reflection-based alternative

Reflection-based factory

public static class MainToolbarElementFactory
{
	private static readonly ConstructorInfo CTOR;

	static MainToolbarElementFactory()
	{
		var type = Type.GetType("UnityEditor.Toolbars.MainToolbarCustom, UnityEditor");
		CTOR = type?.GetConstructor(BindingFlags.Instance | BindingFlags.NonPublic | BindingFlags.Public, null, new[] { typeof(Func<VisualElement>) }, null);
	}

	public static MainToolbarElement Create(Func<VisualElement> createElement)
	{
		return CTOR == null ? null : CTOR.Invoke(new object[] { createElement }) as MainToolbarElement;
	}
}

Example of use

[MainToolbarElement("SampleButton", defaultDockPosition = MainToolbarDockPosition.Right)]
public static MainToolbarElement CreateSampleButton()
{
	return MainToolbarElementFactory.Create(() =>
	{
		var button = new Button(() => Debug.Log("Test"));
		return button;
	});
}

I don't really like the approach of creating an empty slate and then populating it, but that's just me.