Python in a Nutshell, 2nd Edition

Commonly Used Simple Widgets

The Tkinter module provides a number of simple widgets that cover most of the needs of simple GUI applications. This section documents the Button, Checkbutton, Entry, Label, Listbox, Radiobutton, Scale, and Scrollbar widgets.

Button

Class Button implements a pushbutton, which the user clicks to execute an action. Instantiate Button with option text=somestring to let the button show text, or image=imageobject to let the button show an image. You normally also use command=callable to have callable execute without arguments when the user clicks the button. callable can be a function, a bound method of an object, an instance of a class with a _ _call_ _ method, or a lambda.

Besides methods common to all widgets, an instance b of class Button supplies two button-specific methods.

flash	b.flash( ) Draws the user’s attention to button b by redrawing b a few times, alternatively in normal and active states.
invoke	b.invoke( ) Calls without arguments the callable object that is b’s command option, just like b.cget('command')( ). This can be handy when, within some other action, you want the program to act just as if the button had been clicked.

Checkbutton

Class Checkbutton implements a checkbox, which is a little box, optionally displaying a checkmark, that the user clicks to toggle on or off. Instantiate Checkbutton with exactly one of the two options text=somestring to label the box with text, or image=imageobject to label the box with an image. Optionally, use command= ...