How do I delete rectangles in python Tkinter?

Question

I'm trying to delete the old set of rectangles I created. My goal is to have a button that I can press that will delete the old set of rectangles, sort the data, and create new rectangles. I've so far made sense of how to get the button to work I just don't understand how to delete them.

import tkinter as tk
import random

class main():
    def __init__(self):
        self.root = tk.Tk()
        self.w = tk.Canvas(self.root, width=1000, height=1000)
        self.rectangle = self.w.create_rectangle(5, 80, 1000, 1000, fill="white")


        self.text = tk.StringVar()

        self.label = tk.Label(self.w, text = "Click the button to sort the data.")
        self.label2 = tk.Label(self.w, textvariable = self.text)
        self.button = tk.Button(self.w, text="Press to search", command=self.click)


        self.label.pack()
        self.label.place(x=5,y=5)
        self.label2.pack()
        self.label2.place(x=130,y=25)




        self.button.pack()
        self.button.place(x=5,y=25)


        self.random_list()
        self.create_rectangles()

        self.w.pack()


    def click(self):
        self.collection.sort()
        self.w.delete(self.my_rect)


    def random_list(self):
        self.collection = []
        for i in range(0,100):
            n = random.randint(0,100)
            self.collection.append(n)
        print(self.collection)


    def create_rectangles(self):
        self.color = "yellow"
        for i in range(100):
            random_num = random.randint(80,1080)
            self.my_rect = self.w.create_rectangle(5+(10*i),(random_num),10+(10*i),1000,fill=self.color)



if __name__ == "__main__":
    search = main()
    search.root.mainloop()

You *can't* delete the rectangles, because you didn't save all of the ID numbers returned by `.create_rectangle()` - you only saved the last one, in `self.my_rect`. Either append the IDs to a list, or assign a tag to all of the rectangles as you create them (which will allow you to delete them all at once by passing that tag name to `.delete()`). — jasonharper, May 27 '20 at 20:57
That makes sense. I'll go about learning how to do this. Thanks for the direction! — Suezzeus, May 27 '20 at 20:59
Possible Duplicate? https://stackoverflow.com/questions/23690993/how-do-we-delete-a-shape-thats-already-been-created-in-tkinter-canvas/23692118 — 12944qwerty, May 27 '20 at 20:59
@jasonharper: _"You can't delete the rectangles"_ is a false statement. It's more difficult because the ids aren't saved, but they can still be deleted. — Bryan Oakley, May 27 '20 at 21:06
The simple way is to assign a tag to the rectangles: `self.w.create_rectangle(..., tag='rect')`, then delete those rectangles by `self.w.delete('rect')`. — acw1668, May 28 '20 at 02:16

score 0 · Accepted Answer · answered May 27 '20 at 20:59

If the rectangles are the only shapes on the canvas, you could use self.w.delete(tk.ALL).

Otherwise, you will need to keep track of your rectangles in a list. Currently, you overwite self.my_rect every time you create a rectangle. Here is a solution:

def click(self):
    self.collection.sort()
    for rect in self.rects:
        self.w.delete(rect)


 def create_rectangles(self):
        self.color = "yellow"
        self.rects = []
        for i in range(100):
            random_num = random.randint(80,1080)
            rect = self.w.create_rectangle(5+(10*i),(random_num),10+(10*i),1000,fill=self.color)
            self.rects.append(rect)

This should delete the rectangles.

How do I delete rectangles in python Tkinter?

1 Answers1