Swing Hacks

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Chapter 5, Windows, Dialogs, and Frames

#39 Spin Open a Detail Pane

HACK

to ever have a reference to the dialog. With DialogEarthquakeCenter, how-

ever, you need that reference. So, instead, you provide the usual

JOptionPane

values (message, message type, user options, etc.) to the

JOptionPane

con-

structor, and then derive a dialog with

createDialog( )

. Don’t worry—you

still end up with the same option dialog.

Next, you create a

DialogEarthquakeCenter

from that dialog. Then you can

return to the dialog,

pack( ) it, and make it visible. One hazard of working

with the

JOptionPane dialog is that it is modal, meaning it will block the

AWT event-dispatch thread when shown; thus, it won’t shake because

DialogEarthquakeCenter won’t get any animation callbacks from Timer. To

get around this, I just made the dialog non-modal—after all, the user proba-

bly isn’t going to be able to click it when it’s moving. Another option might

be for the

DialogEarthquakeCenter constructor to remember if its dialog is

modal, and to reset this state in

stopShake( ).

Unfortunately, there’s not a great way to show the effect of this animation in

book form. The best I can suggest is that you compile and run the hack for

yourself. While you’re at it, change some of the constant values to see the

effect of longer or shorter shake cycles, distances, and durations.

H A C K

#39

Spin Open a Detail Pane Hack #39

You don’t want to bombard the ...