How to Bind Enter Key to a Function in Tkinter

In this tutorial, We will introduce how to bind Enter key to a function in Tkinter.

Bind event to a function

The Enter key pressing is an event, like button clicking, and we could bind functions or methods to this event to make the event trigger the specified function.

widget.bind(event, handler)

If the event occurs, it will trigger the handler automatically.

Bind key press to a function

import tkinter as tk

app = tk.Tk()
app.geometry("200x100")

def callback(event):
    label["text"] = "You pressed Enter"

app.bind('<Return>', callback)

label = tk.Label(app, text="")
label.pack()

app.mainloop()

def callback(event):
    label["text"] = "You pressed Enter"

The event is a hidden argument passed to the function. It will raise TypeError if you don’t give it in the function input argument.

app.bind('<Return>', callback)

We bind the callback function to the <Return> event, or in other words, Enter key pressing event.

Bind key press to a function in Class method Example

import tkinter as tk

class app(tk.Frame):
    def __init__(self):
        self.root = tk.Tk()
        self.root.geometry("300x200")
        self.label = tk.Label(self.root, text="")
        self.label.pack()
        self.root.bind('<Return>', self.callback)
        self.root.mainloop()


    def callback(self, event):
        self.label["text"] = "You pressed {}".format(event.keysym)
    
app()

This class implementation is similar to the above method.

We put the keysym attribute of the event object in the shown label.

keysym is the key symbol of the keyboard event. Enter is Return as we introduced above.