如何在不中断tkinter主循环的情况下运行函数，又如何从该函数向主循环中的小部件发送信息？

Question

Apologies if this has been asked before, but I couldn't find a clear answer. I'm writing a GUI to control a motor from a raspberry pi, and it's on a touchscreen. I've written some code which opens the built in matchbox keyboard when the Entry widget comes into focus, but this halts my entire tkinter window in the background, meaning that the user cannot see what they are entering appear in the Entry until they have closed the keyboard, and also that the screen often tears and looks horrible when it hangs in the background. Is there anyway to run this command: def createNumpad(event=none): os.system('matchbox-keyboard numpad') so that the tkinter window doesn't freeze while the keypad is open? Thanks!

Answer 1

This is the relevant code from a SO answer changed to fit Tkinter:

import subprocess

def createNumpad(event)
    try:
        subprocess.Popen(["matchbox-keyboard", "numpad"])
    except FileNotFoundError:
        pass

def deleteNumpad(event):
    subprocess.Popen(["killall","matchbox-keyboard"])

#
entry.bind("<Enter>", createNumpad)
entry.bind("<Leave>", deleteNumpad)