MovieClip extension - actionscript-3

Question

I have been trying to develop a CustomButton class that extends MovieClip, however I am having problems. I have got this error:
ArgumentError: Error #1063: Argument count mismatch on
mkh.custombutton::CustomButton(). Expected 2, got 0. at
flash.display::Sprite/constructChildren() at flash.display::Sprite()
at flash.display::MovieClip()
I've tried to debug my code, but it says
"Cannot display source code at this location."
I am not sure where is the problem, but I suppose it's in the constructor:
public function CustomButton( buttonlabel:String, animationAR:Array, active:Boolean=true, animated:Boolean = false, type:String = "free", group:int = 0 )
I would be very grateful if anyone helped me. Thank you.
EDIT2: I think I know why it's not appearing, so nevermind.

Answer 1

Seems like you must be instantiating CustomButton without passing it any arguments.
Like so:
var cBtn = new CustomButton();
However, you constructor has 2 arguments that must be passed - buttonLabel and animationAR (the rest are OK because they are assigned a default value).
So you should be doing something like this:
var cBtn = new CustomButton('Test', someArray);

Answer 2

I think I know what the problem is, now I hope I can explain to you clearly enough (English is not my first language). Did you by any chance make a graphic MovieClip in the Flash program and linked it to your CustomButton class? If so, be careful with the instances you might have on the stage, because when Flash creates the Sprites/Movieclips objects that are on the stage it calls their constructor without any parameters.
To avoid this, either:
Set default values for all parameters in your CustomButtonClass (EDIT: which would solve your problem, but is not very good practice)
Use addChild to put instances of your Button onto the stage (I recommend this one)
Hope this helps!

Answer 3

public function CustomButton(
buttonlabel:String,
animationAR:Array,
active:Boolean=true,
animated:Boolean = false,
type:String = "free",
group:int = 0
);
That's how you defined your constructor. This means that the first 2 arguments (buttonlabel abd animationAR) are required arguments. The rest are optional.
Now if you try to instantiate this like
var cb:CustomButton=new CustomButton();
You are not passing any arguments to the constructot, which will throw that error.
Note that this is what happens when you create the object directly in the UI.
A way to fix this would be to redefine the constructor as:
public function CustomButton(
buttonlabel:String="CustomButton",
animationAR:Array=[],
active:Boolean=true,
animated:Boolean = false,
type:String = "free",
group:int = 0
);
This makes all arguments optional and should work. Of course, you'll be best off putting the default value of the arguments as something you know will work. For example, in my example, the empty array default for animationAR could break your code, in which case you need to add this to the constructor body:
if(animationAR.length==0) {
animationAR.push(new Animation());
//YOU WILL HAVE TO CHANGE THIS LINE TO CORRESPOND TO YOUR CODE
}
OR ELSE, you could instantiate the object as
var cb:CustomButton=new CustomButton("My Crazy-ass CustomButton", animArray);