turtle.onkey() function in Python

20 Sep turtle.onkey() function in Python

Posted at 11:00h in Python Turtle by Studyopedia Editorial Staff 0 Comments

The turtle.onkey() function binds a function to a key-press event. The turtle screen must be listening for events (listen()) for this to work.

Syntax: turtle.onkey(fun, key)
Parameters: fun – a function with no arguments; key – a string representing the key (e.g., “a”, “space”, “Up”).

Let us see an example to implement the turtle.onkey() function in Python:

Demo32.py

# turtle.onkey() function in Python
# Code by Studyopedia

import turtle

window = turtle.Screen()
t = turtle.Turtle()

def move_forward():
    t.forward(50)

def move_backward():
    t.backward(50)

window.onkey(move_forward, "Up")     # Bind up arrow key
window.onkey(move_backward, "Down")  # Bind down arrow key
window.listen()                      # Start listening for events

window.mainloop()

The following is the output:

turtle.onkey() function in Python

In the above code, we followed the below steps:

Import the module: import turtle loads Python’s turtle graphics library.
Create the screen: window = turtle.Screen() opens the drawing window.
Create the turtle: t = turtle.Turtle() creates the turtle you’ll control.
Define forward action: def move_forward(): t.forward(50) moves the turtle forward 50 units when called.
Define backward action: def move_backward(): t.backward(50) moves the turtle backward 50 units when called.
Bind Up key: window.onkey(move_forward, “Up”) triggers move_forward() when the Up arrow is pressed.
Bind Down key: window.onkey(move_backward, “Down”) triggers move_backward() when the Down arrow is pressed.
Enable key listening: window.listen() starts listening for keyboard events; without this, key presses won’t be captured.
Run event loop: window.mainloop() keeps the window open and responsive to key presses until it’s closed.