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But there's a new problem now. If you compile and run the projector as
it is currently, you have no ready way to quit the program!
Your computer will display "Hello, World" at you indefinitely.
That's a terrible design.
You need to build in a way for your user to quit the program once it's gotten its point across.
The quickest way to do this is to put a QUIT (or EXIT) button onscreen somewhere under "Hello, World".
Back to the Tool Palette!
Click once on the button tool (the one which looks like a button), then
click somewhere on the Stage and type the word QUIT in the button that
appears (or EXIT for Windows).
Ready? Not yet.
You have to define an action associated with that button; simply typing the word QUIT in it isn't enough.
The button you just created should appear in the Cast window, probably
in box number four. Click once on it, then click the script icon at the
top of the Cast window — this should look like a white box with lines
meant to represent indented scripting in it. Another Script window will
open — in this case, a Button script. In its window you will see:
on mouseUp
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end
With a cursor flashing between the lines, as it was with your Score script.
All you have to do to make your QUIT button a real QUIT button is add one word:
on mouseUp
QUIT
end
This is telling Director (and the computer on which it's running):
"When the user releases the mouse button (on mouseUp), QUIT the program."
Note this event takes place on a mouseUp event, not a mouseDown
event. This is a standard User Interface (UI) design; generally button
events are not triggered by mouse action until the mouse button is
released. This permits the user to cancel the action by dragging the
mouse away before releasing the button. All well-written programs
behave in this fashion.
As with the Score script you entered, note that there are no double-spaces in your button script.
Now you can close the script window and — hey presto — you have an authentic QUIT button.
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A brief introduction to Director