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custom widgets and classes

Your new function needs to create widgets

and event handlers Each widget

When you’re wiring up the widgets in the interface, you need event handlers needs its own
to respond to changes in the state of the widgets. If someone clicks the
checkbox to play the track, the track_toggle() event handler gets called event handler.
and switches the track on or off.
But if you are creating several checkoxes, you are going to need a separate event
handler for each of them.
That’s why you have local functions inside create_gui(). As well as creating
new widgets for the interface, it also uses the local functions to create new
event handlers.

track_toggle() change_volume()

This is a new checkbox This is a new slider
event handler. event handler.

This is a new This is a new Scale.
Checkbutton.

create_gui()

Now, let’s update the program to use this new function.

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