Python Tkinter – Call Function on Button Click
When a Tkinter Button is clicked, you can call a function using command option. Assign the command option with the function name you would like to call when the button is clicked.
Pseudo Code – Call Function on Button Click
Following is a pseudo code to call a function when the button is clicked.
def someFunction: function body tkWindow = Tk() button = Button(tkWindow, command=someFunction)
Or you can also assign the command after defining the button.
def someFunction: function body tkWindow = Tk() button = Button(tkWindow) button['command'] = someFunction
Example 1: Call Function on Button Click
In this example, we will create a function, a Tkinter Button, and assign the function to Button, such that when user clicks on the Button, the function is called.
from tkinter import * from tkinter import messagebox tkWindow = Tk() tkWindow.geometry('400x150') tkWindow.title('PythonExamples.org - Tkinter Example') def showMsg(): messagebox.showinfo('Message', 'You clicked the Submit button!') button = Button(tkWindow, text = 'Submit', command = showMsg) button.pack() tkWindow.mainloop()
Please remember these things while providing a function to be called when the user clicks the button.
- Define the function prior to the button definition.
- The value to the command option should be the function name as is and not as a string with any quotes around it.
Concluding this tutorial of Python Examples, we learned how to call a function when Tkinter Button is clicked.