Display calculation of GUI in text box

I'm trying to display a calculation my code does into a textbox in my GUI. For example:

htextbox1 = uicontrol('Style','text','String','area','Position',...
    [150,220,100,30]);
set(htextbox1,'Visible','Off')
r = 0;
x = 2;
y = 4;
r = x^2 + y^2;
if r ~=0
   set(htextbox1,'Visible','On')
   set(htextbox1,'String',num2str(r))
end

and I want the textbox to display the value of r. How can I do this? Nothing I've tried works. Thanks.

[Walter Roberson]

Your exact code works for me when pasted into my command window.

Answer 1

[Walter Roberson]

Your exact code works for me when pasted into my command window.

One thing I would recommend is that you use Units when you give the Position parameter.

[Adam Glick]

I figured out what the issue was. It was a problem with a previous part of the code. How can I add units and have the variable r displayed?