Lionel

Hi Everyone. This is my first attempt at the On Screen Calculator. My commits are not small, and I apologize for that Zee. The only functionality that I see that throws an error is clicking on operators more than once before clicking on another number. I don't think some of the edge cases I addressed were necessary, but since I'm building these applications for my portfolio I'd like it to be fairly clean.

Thank you for your help.
You could make the positive-negative handler smart enough to do nothing in the case it's not appropriate for it to do things. That way you don't get into a "did I bind yet?" or "I bound too many times!" mess.