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mixing multiple tracks

The DJ wants to play more than one track

The World Music Mixing Expo is only a few weeks away. Your DJ friend is
thrilled with the work you’ve done, but now he has a few extra requirements.
Just playing one track isn’t enough. To be useful, the program needs to be able I can fade a track
to mix several tracks together at the same time. Each track needs its own in and out, but that‛s
graphical interface elements (or widgets). not enough. I need to
be able to mix several
tracks together.

How will you create the widgets for each track?

To play and control a single track, you created two widgets on the GUI: a
check button to start and stop the track and a scale to change the volume. Then
you added event-handling code to hook those widgets up to the sound
system.

Track.
Control the
Turn on/off. volume.

To play multiple tracks together, you just need more of the same. Each track will
need its own set of widgets and its own event handlers to connect the widgets and
the track together. Then, each set of widgets needs to be added to the same
window in the GUI.

Let’s generate the widgets and event handlers.

350 Chapter 10