Using Async calls in a Util class

Question

I have a Utility class that I want to put code in that I'm reusing over and over again.  This includes Async.handleEvent calls.  If I call an instance of the Util class from a [Test(async)] method, can I use the Async call in that other event?
When I tried this in my code, it said that it "Cannot add asynchronous functionality to methods defined by Test,Before or After that are not marked async" but my [Test] is marked as async. And when I was in the same class, I was able to have non-Test methods make Async calls.
Thanks for the help!
Mocked up Example (please note these are two separate files):
// Test.as
package
    import TimerUtil;
    public class Test
        [Test(async)]
        public function waitForTimer():void
            TimerUtil.newTimer();
// TimerUtil.as
package
    import flash.events.TimerEvent;
    import flash.utils.Timer;
    import org.flexunit.async.Async;
    public class TimerUtil
        private static var instance:TimerUtil;
        private var timer:Timer;
        private static const TIME_OUT:int = 1000;
        public static function newTimer() : void
            if (!instance) instance = new TimerUtil();
            instance.timer = new Timer(1000, 5);
            instance.timer.start();
            instance.waitForFifthTick();
        private function waitForFifthTick() : void
            Async.handleEvent(this, instance.timer, TimerEvent.TIMER, handleTimerTick, TIME_OUT);
        private function handleTimerTick ( evt:TimerEvent, eventObject:Object) : void
            if ( timer.currentCount == 5 )
                // We are at the Fifth click, move on.
            else
                Async.handleEvent(this, instance.timer, TimerEvent.TIMER, handleTimerTick, TIME_OUT);
Message was edited by: zyellowman2
I missed a comma.  And a few "instance"s

Answer 1

Yes, you can put async calls in utility classes or wherever you want. That isn't the issue here though.
In your test you call TimerUtil.newTimer()
That code creates a timer and then returns. Then your test returns. At that moment, FlexUnit sees that your test has finished and that there are no outstanding registered asynchronous events so it declares the test a success. Then, a second later, your other method executes and tries to register an async call. FlexUnit has no idea what test this pertains to, or why this call is being made as it is no longer in the context of the original test, hence the message you are receiving that you can only using Async calls inside of a method marked with a Async... as, in FlexUnit's opion, the method that is executing this code no longer has anything to do with a test with an async param.
The best way to think about this is a chain that cannot be broken. As soon as a method finishes executing with, FlexUnit will declare it a success unless we are waiting on something else (an async event of some sort) That is what the Async syntax really does, it tells the framework not to declare this method a success just yet, and that there is something else we need to account for to make that decision.
So, right now, in your newTimer() you don't let the framework know that you will be waiting for an async event. Therefore, when that method and the test method is over, so is the test.
Mike