UIButton OnClick function with a string parameter shows as "object"

[Mastro]

I wanted by button to call a function in a script to load the next scene.

Not sure if this is the best way but I created an empty gameobject and dragged my script on it. It has a public function and a parameter for string levelName.  However when I point to that object in the UIButton and that method, the arg0 wants an object and I can't type in the value in the designer. Using nGui 3.6.0

[ArenMook]

You can only find it to a property, such as game object's name. You can't specify a value directly by typing it.