[Tkinter-discuss] Communicating between objects w/o class and/or global?

[John McMonagle]

> Recently I posted, on this Forum, a msg titled:  "Tkinter mouse-
> event w/o class and/or global?" It was successfuly  [RESOLVED] .
> 
> ow I have related Question:
> 
> I have two (c1 & c2) Canvas instances. If I mouse-click on one of the
> canvases (or more likely on a drawn item on the canvas, e.g. on a
> rectangle), I would like to change the background color of the other 
> canvas.
> 
> Can I do it without classes (OOP) and/or global-variables?
> 

Sure can, you just have to pass the widget id as a parameter to the function.

For example:

import Tkinter as tk

root = tk.Tk()

c1 = tk.Canvas(root, bg='green')
c2 = tk.Canvas(root, bg='red')
c1.pack()
c2.pack()

def changeColour(event, c):
    if c.cget('bg') == 'red':
        c.configure(bg='green')
    else:
        c.configure(bg='red')
        
c1.bind('<Button-1>', lambda e, c=c2: changeColour(e, c))
c2.bind('<Button-1>', lambda e, c=c1: changeColour(e, c))

root.mainloop()



Regards,

John