ACTIONSCRIPT 3 Developer’s Guide en

ACTIONSCRIPT 3.0 DEVELOPER’S GUIDE
Handling events
import flash.events.TimerEvent;
import flash.utils.Timer;
/**
* The Timer that will be used for the alarm.
*/
public var alarmTimer:Timer;
...
/**
* Instantiates a new AlarmClock of a given size.
*/
public override function initClock(faceSize:Number = 200):void
{
super.initClock(faceSize);
alarmTimer = new Timer(0, 1);
alarmTimer.addEventListener(TimerEvent.TIMER, onAlarm);
}
The Timer instance defined in the AlarmClock class is named alarmTimer. The initClock() method, which
performs necessary setup operations for the AlarmClock instance, does two things with the alarmTimer variable.
First, the variable is instantiated with parameters instructing the Timer instance to wait 0 milliseconds and only trigger
its timer event one time. After instantiating alarmTimer, the code calls that variable’s addEventListener() method
to indicate that it wants to listen to that variable’s timer event. A Timer instance works by dispatching its timer event
after a specified amount of time has passed. The AlarmClock class will need to know when the timer event is
dispatched in order to set off its own alarm. By calling addEventListener(), the AlarmClock code registers itself as
a listener with alarmTimer. The two parameters indicate that the AlarmClock class wants to listen for the timer event
(indicated by the constant TimerEvent.TIMER), and that when the event happens, the AlarmClock class’s onAlarm()
method should be called in response to the event.
In order to actually set the alarm, the AlarmClock class’s setAlarm() method is called, as follows:
Last updated 6/6/2012
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