Question

I have a base class like this

class Base {
    public var space:Number;
}

which gets extended by

class Desc extends Base {

    override public function set space( space:Number ):void {
        //code
    } 

}

This doesn’t compile. Say, you don’t have control of the base class, what ways is there implement the same thing?

The obvious is create a function setSpace(), but this object is being embedded in an already existing system that use the public space.

Thanks in advance.

Answer 1

Your base class should be defined that way:

class Base {

    // Don't use public variables. Make them private and define setters and getters 
    private var space_:Number;

    public function get space():Number {
        return space_;
    }

    public function set space(v:Number):void {
        if (space_ === v) return;
        space_ = v;
    }

}

And then it can be overriden that way:

class Desc extends Base {

    override public function set space( space:Number ):void {
        //code
    } 

}

Edit:

I missed the part where you say you don’t have control over the base class. In that case, hope that space is defined as a getter/setter (it should be if the class is implemented properly). If not, you’ll indeed have to use a function such as getSpace and setSpace.