Swing Hacks

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Chapter 10, Audio

#73 Play a Sound with QuickTime for Java

HACK

example, if the media could play in both directions and you wanted to be

notified when it reached the beginning of the movie too, you’d pass

StdQTConstants.triggerAtStop | StdQTConstants.triggerAtStart

.

Next, you have to use

callMeWhen( )

to register the callback. This signs you

up for one callback—if you’re called and are still interested in future events,

you have to reregister with another

callMeWhen( )

.

When the sound finishes, the callback calls

execute( ). This is when you shut

everything down, as in the other hacks. Notice that you close down Quick-

Time with

QTSession.close( ), the obvious counterpart to QTSession.open( ).

There are some issues about how well it works on Windows: it sometimes

hangs for me, and you may want to use the safer

QTSession.exitMovies( ),

which only closes down some of QTJ, but the rest seems to get taken care of

by QTJ itself, as I’ve never had a problem.

And one more bit of arcane QTJ lore: the code makes a call to

TaskAllMovies.addMovieAndStart( ). This helps deal with the fact that mov-

ies have to explicitly be given CPU time, with calls to a

task( ) method, in

order to work.

TaskAllMovies is a convenience Thread that can periodically

make this tasking call for all your movies. If you’ve read Chris’ book on

QTJ, you would think that this isn’t necessary, as having the AWT event-

dispatch thread usually ...