Create RadioButton To hide text box

I am trying to create a radio button that when clicked an existing textbox is hidden.

here is my code:

if

(RadioButtonList22.rawValue ==

true)

TextBoxExc1.presence = "hidden";

else

TextBoxExc1.presence = "visible";

I am inserting this under a click event on my RadioButtonList22.

Nothing happens when I test the form.  I click the radio button by the text box does not hide.

Thank you!