{"id":1734,"date":"2020-12-21T02:24:10","date_gmt":"2020-12-21T02:24:10","guid":{"rendered":"https:\/\/www.pythontutorial.net\/?page_id=1734"},"modified":"2022-05-13T01:08:19","modified_gmt":"2022-05-13T01:08:19","slug":"tkinter-after","status":"publish","type":"page","link":"https:\/\/www.pythontutorial.net\/tkinter\/tkinter-after\/","title":{"rendered":"How to Schedule an Action with Tkinter after() method"},"content":{"rendered":"\n

Summary<\/strong>: in this tutorial, you’ll learn how to use the Tkinter after()<\/code> method to schedule an action after a timeout has elapsed.<\/p>\n\n\n\n

Introduction to Tkinter after() method #<\/a><\/h2>\n\n\n\n

All Tkinter widgets have the after()<\/code> method with the following syntax:<\/p>\n\n\n

widget.after(delay, callback=None<\/span>)<\/code><\/span>Code language:<\/span> Python<\/span> (<\/span>python<\/span>)<\/span><\/small><\/pre>\n\n\n
The after()<\/code> method calls the callback<\/code> function once after a delay<\/code> milliseconds (ms) within Tkinter’s main loop.<\/p>\n\n\n\n
If you don’t provide the callback<\/code>, the after()<\/code> method behaves like the time.sleep()<\/code> function. However, the after()<\/code> method uses the millisecond instead of the second as the unit.<\/p>\n\n\n\n
Tkinter after() method example #<\/a><\/h2>\n\n\n\n
Let’s see the following program:<\/p>\n\n\n
import<\/span> tkinter as<\/span> tk\nfrom<\/span> tkinter import<\/span> ttk\nimport<\/span> time\n\n\nclass<\/span> App<\/span>(tk.Tk)<\/span>:<\/span>\n    def<\/span> __init__<\/span>(self)<\/span>:<\/span>\n        super().__init__()\n\n        self.title('Tkinter after() Demo'<\/span>)\n        self.geometry('300x100'<\/span>)\n\n        self.style = ttk.Style(self)\n\n        self.button = ttk.Button(self, text='Wait 3 seconds'<\/span>)\n        self.button['command'<\/span>] = self.start\n        self.button.pack(expand=True<\/span>, ipadx=10<\/span>, ipady=5<\/span>)\n\n    def<\/span> start<\/span>(self)<\/span>:<\/span>\n        self.change_button_color('red'<\/span>)\n        time.sleep(3<\/span>)\n        self.change_button_color('black'<\/span>)\n\n    def<\/span> change_button_color<\/span>(self, color)<\/span>:<\/span>\n        self.style.configure('TButton'<\/span>, foreground=color)\n\n\nif<\/span> __name__ == \"__main__\"<\/span>:\n    app = App()\n    app.mainloop()<\/code><\/span>Code language:<\/span> Python<\/span> (<\/span>python<\/span>)<\/span><\/small><\/pre>\n\n\n
The program consists of a button. When you click the button:<\/p>\n\n\n\n