AS3 How to make a variable hold only objects that implements a given interface

Question

I have two classes, lines and points. Both class implements 'highlightable'. I want to make a variable that can hold different type of objects that implements the 'highlightable' interface.

var currentObject:lines; //Won't work. It can only hold 'lines' object.
var currentObject:points; //won't work because it can only hold 'points' object.
var currentObject:Object; //Won't work because it can hold any objects. I want it to hold only those objects that implements the 'highlightable' interface.

Is it possible?

Thanks

Answer 1

All you need to do is make your variable the type of your interface.

var currentObject:highlightable = new classA();

or

var currentObject:highlightable = new classB();

Where both classA and classB implement the highlightable interface.

Answer 2

Just implement the interface in your class so you force the pattern.

public interface IHighlightable

public class Lines implements IHighlightable
public class Points implements IHighlightable


// for the usage you type cast as the interface
var currentObject:IHighlightable = new Lines()
var currentObject:IHighlightable = new Points()

**Be sure to follow naming conventions