MACROMEDIA FLASH 8-LEARNING ACTIONSCRIPT 2.0 IN FLASH, Руководство пользователя

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340 Handling Events
Specifying events for on or onClipEvent methods
To use an
on()
or
onClipEvent()
handler, attach it directly to an instance of a button or
movie clip on the Stage and specify the event you want to handle for that instance. For a
complete list of events supported by the
on()
and
onClipEvent()
event handlers, see
on
handler
and
onClipEvent handler
in the ActionScript 2.0 Language Reference .
For example, the following
on()
event handler executes whenever the user clicks the button to
which the handler is attached:
on (press) {
trace("Thanks for pressing me.");
}
You can specify two or more events for each
on()
handler, separated by commas. The
ActionScript in a handler executes when either of the events specified by the handler occurs.
For example, the following
on()
handler attached to a button executes whenever the mouse
rolls over and then off the button:
on (rollOver, rollOut) {
trace("You rolled over, or rolled out");
}
You can also add key press events using
on()
handlers. For example, the following code traces
a string when you press the number 3 on the keyboard. Select a button or movie clip instance,
and add the following code to the Actions panel:
on (keyPress "3") {
trace("You pressed 3")
}
Or, if you want to trace when the Enter key is pressed by a user, you could use the following
code format. Select a button or movie clip instance, and add the following code to the Actions
panel:
on (keyPress "<Enter>") {
trace("Enter Pressed");
}
Select Control > Test Movie, and press the Enter key to see the string trace to the Output
panel. If nothing traces, select Control > Disable Keyboard Shortcuts and try again. For more
information on adding keypress interactivity to your applications, see
Key
.
NO
T
E
Attaching
onClipEvent()
and
on()
handlers is not a recommended practice. Instead, you
should put your code in frame scripts or in a class file, as demonstrated throughout this
manual. For more information, see
“Using event handler methods” on page 330 and
“Attaching code to objects” on page 746 .