How do you update a TkInter ListBox from child window?
I've recently started working on my first TkInter program. I've been able to find answers to most of my questions, but there's one problem I haven't been able to resolve.
At one point in my code, I want the user to be able to input a name in a child window. After clicking a button in this window, an item with the inputted name will be added to a Listbox in the parent window.
My code (with all the unrelated widgets removed) is shown below. If you have an answer, bear in mind that I am a newcomer to TkInter (and programming in general), so please explain it in as much depth as possible.