Python | Binding function in Tkinter

Tkinter is a GUI (Graphical User Interface) module that is widely used in desktop applications. It comes along with the Python, but you can also install it externally with the help of pip command. 
It provides a variety of Widget classes and functions with the help of which one can make our GUI more attractive and user-friendly in terms of both looks and functionality.
The binding function is used to deal with the events. We can bind Python’s Functions and methods to an event as well as we can bind these functions to any particular widget.
Code #1: Binding mouse movement with tkinter Frame. 

Python3

# Import all files from
# tkinter and overwrite
# all the tkinter files
# by tkinter.ttk
from tkinter import *
from tkinter.ttk import *

# creates tkinter window or root window
root = Tk()
root.geometry('200x100')

# function to be called when mouse enters in a frame
def enter(event):
    print('Button-2 pressed at x = % d, y = % d'%(event.x, event.y))

# function to be called when mouse exits the frame
def exit_(event):
    print('Button-3 pressed at x = % d, y = % d'%(event.x, event.y))

# frame with fixed geometry
frame1 = Frame(root, height = 100, width = 200)

# these lines are showing the
# working of bind function
# it is universal widget method
frame1.bind('<Enter>', enter)
frame1.bind('<Leave>', exit_)

frame1.pack()

mainloop()

Output:

Code #2: Binding Mouse buttons with Tkinter Frame 

Python3

# Import all files from
# tkinter and overwrite
# all the tkinter files
# by tkinter.ttk
from tkinter import *
from tkinter.ttk import *

# creates tkinter window or root window
root = Tk()
root.geometry('200x100')

# function to be called when button-2 of mouse is pressed
def pressed2(event):
    print('Button-2 pressed at x = % d, y = % d'%(event.x, event.y))

# function to be called when button-3 of mouse is pressed
def pressed3(event):
    print('Button-3 pressed at x = % d, y = % d'%(event.x, event.y))

## function to be called when button-1 is double clocked
def double_click(event):
    print('Double clicked at x = % d, y = % d'%(event.x, event.y))

frame1 = Frame(root, height = 100, width = 200)

# these lines are binding mouse
# buttons with the Frame widget
frame1.bind('<Button-2>', pressed2)
frame1.bind('<Button-3>', pressed3)
frame1.bind('<Double 1>', double_click)

frame1.pack()

mainloop()

Output:

Code #3: Binding keyboard buttons with the root window (tkinter main window). 

Python3

# Import all files from
# tkinter and overwrite
# all the tkinter files
# by tkinter.ttk
from tkinter import *
from tkinter.ttk import *

# function to be called when
# keyboard buttons are pressed
def key_press(event):
    key = event.char
    print(key, 'is pressed')

# creates tkinter window or root window
root = Tk()
root.geometry('200x100')

# here we are binding keyboard
# with the main window
root.bind('<Key>', key_press)

mainloop()

Output:

Note: When we bind keyboard buttons with the tkinter window, whenever we press special characters we will only get space while in the case of alphabets and numerical we will get actual values (in the string).