tkinter example dynamic circle (snippet)

Python tkinter (gui) example 'dynamic circle'

dynamic circle

Python tkinter example: dynamic circle

from tkinter import * # Import tkinter

width = 200
height = 200

class MainGUI:
    def __init__(self):
        window = Tk() # Create a window
        window.title("Dynamic Circles") # Set title

        self.radius = 20

        self.tagNumber = 0
        self.canvas = Canvas(window, bg = "white", width = width, height = height)
        self.canvas.create_oval(width / 2 - self.radius, height / 2 - self.radius,
            width / 2 + self.radius, height / 2 + self.radius, tags = str(self.tagNumber))
        self.canvas.pack()

        self.canvas.bind("<Button-1>", self.addACircle)
        self.canvas.bind("<Button-3>", self.removeACircle)

        window.mainloop() # Create an event loop

    def addACircle(self, event):
        self.tagNumber += 1
        self.radius += 5
        self.canvas.create_oval(width / 2 - self.radius, height / 2 - self.radius,
            width / 2 + self.radius, height / 2 + self.radius, tags = str(self.tagNumber))    

    def removeACircle(self, event):
        self.canvas.delete(str(self.tagNumber))    
        self.radius -= 5
        self.tagNumber -= 1

MainGUI()

Useful links

• Learn Tkinter: https://pythonbasics.org/tkinter/
• Wikipedia tkinter: https://en.wikipedia.org/wiki/Tkinter