Python tkinter: changing color for a recently clicked button

Question

I'm trying to have a program which would have a grid of 8x8 buttons which would on-click change their color My code looks like this:

def Function(self):
    for i in range(8):
        for j in range(8):
            a=Button(self,width=2,height=1,command=lambda widget="button"+str(i)+str(j):Click1(self,widget))
            a.grid(row=i,column=j)

def Click1(self):
    a["bg"]="blue"

The problem I have with this is that I keep getting an error saying:

NameError: name 'Click1' is not defined

any solutions for this?

Answer 1

You are not saving references to the Buttons, so you can't change them later on. What you should do is save references to the Buttons, for example in a list of lists (like a grid), so you can access them with the row and column number.

Here's a working example:

from Tkinter import *

class App():
    def __init__(self, root):
        self.root = root

    def Function(self):
        self.grid = []
        for i in range(8):
            row = []
            for j in range(8):
                row.append(Button(self.root,width=2,height=1,command=lambda i=i, j=j: self.Click1(i, j)))
                row[-1].grid(row=i,column=j)
            self.grid.append(row)

    def Click1(self, i, j):
        self.grid[i][j]["bg"]="blue"

root = Tk()
app = App(root)
app.Function()
root.mainloop()