Sending multiple types of variables to a function

[ropeGun]

Hello Community!

I know that it is possible to feed more than one variable to a function -- even if the variables are of different types (the attached code works if I take away all references to the MouseEvent; that is, if I only pass the a, b, and c variables to the function). My question is, can I make this work when I also want to pass a MouseEvent variable to the function as well? In other words, is it possible to place something in the spot where I have the "???" that satisfies the functions demand for an answer to the MouseEvent? I have tried "null", "void", and "undefined" but these do not work.

Any input would be appreciated.

-john

[Andrei1-bKoviI]

To my knowledge, event listeners expect only one parameter - event.

If you need other parameters available to the listener - you need to either use global variables, or target's properties or you may want to write a custom event that will have custom event properties in addition to the native ones.

[Guest]

You can do it if you create an anonymous function your event listener responds to.

myThing.addEventListener(MouseEvent.CLICK,
function sendMoreVars(e:MouseEvent){
moreThanOneVar(a,b,c,e)
})


Cheers,
FlashTastic

[Andrei1-bKoviI]

Yes, it is one of the way of doing it but I think anonymous functions in event listeners are not such a good idea from GC standpoint. How does one remove it? I believe other workarounds are more solid.

[Guest]

You are correct Andrei, it would be difficult (if not impossible) to remove this event listener. Thanks for pointing out my mistake.

Cheers,
FlashTastic

[ropeGun]

Andrei1,

Which other workarounds do you think are better?

Regards,
ropeGun

[Andrei1-bKoviI]

The way you have written your code you don't need to pass additional variables. You declared a, b, and c as global vars in this scope - so they are readily available to the listener. Even if their values will change - listener will capture that. Another story will be if you attach the same listener to multiple buttons and would like to read different variables depending on what button is clicked - here you will need a work around. If this is the case - please tell more about your task.

As it is now, the code should look like this:

var a:String = "a";
var b:uint = 3;
var c:Array = new Array("apples", "oranges", "kiwi");
function moreThanOneVar(me:MouseEvent):void {
trace(a);
trace(b);
trace(c);
trace(me.currentTarget.name);
};
this.myButton.addEventListener(MouseEvent.CLICK, moreThanOneVar);