Tkinter - unable to move polygon on the screen-CodePudding

I'm learning Python and I decided to make a GUI. It's a simple GUI that'll just move a polygon on the screen. But it seems the thread keep getting stuck in the update method.

class main():

    render = Render(500, 500)

    while True:
        render.update()
        time.sleep(1)


class Render:

    def __init__(self, width, height):
        self.window = Tk()
        self.window.config(height=500, width=500)
        self.canvas = Canvas(self.window, width = width, height = height, 
                             background = "white")
        self.deltaX = 0


    def update(self):
        print(self.deltaX)
        self.canvas.create_polygon(150   self.deltaX, 75, 225   self.deltaX, 0, 
                                   300   self.deltaX, 75, 225   self.deltaX, 150, 
                                   outline = "black", fill = "")
        self.canvas.pack()
        self.window = mainloop()
        self.deltaX  = 10
        return None

Sorry if this is dumb, but I'm very new to Python.

CodePudding user response：

You shouldn't call mainloop like that, probably you should only call it once. See Tkinter understanding mainloop

CodePudding user response：

There's a couple ways to write this out. No matter how you do it you only need to call/draw the object once and then update it through your loop

It can be as simple as creating a property in the constructor and then updating via a method

from tkinter import *
import time

class Render:

    def __init__(self, width, height):
        self.window = Tk()
        self.window.config(height=500, width=500)
        self.canvas = Canvas(self.window, width = width, height = height, 
                             background = "white")
        self.deltaX = 2
        self.poly = self.canvas.create_polygon(150   self.deltaX, 75, 225   self.deltaX, 0, 
                                   300   self.deltaX, 75, 225   self.deltaX, 150, 
                                   outline = "black", fill = "")
        self.canvas.pack()
    def update(self):
        self.canvas.move(self.poly, self.deltaX, 0)
        self.window.update()    


class main():

    render = Render(500, 500)

    while True:
        render.update()
        time.sleep(1)