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How to extend the AS3 Point class correctly?

I need a little more information from my points, so I thought I would add the previousX, the previous one, so that I could get deltaX and deltaY. Now this works fine if I make a simple standalone class.

I think, however, that I would like to extend the flash.geom.Point class to take advantage of the other functions and calculations that it offers.

So, I expanded the point and changed the x and y settings as needed. When I compile, I get an error that these setters are not marked to override when they should be. Therefore, I override, but then I get an error message that says that they are not overriding any function.

Any clue where I squinted?

Here is the class:

package net.jansensan.geom
{
    import flash.geom.Point;

    /**
     * @author Mat Janson Blanchet
     */
    public class UpdatablePoint extends Point
    {
        private var _previousX : Number = 0;
        private var _previousY : Number = 0;
        private var _deltaX    : Number = 0;
        private var _deltaY    : Number = 0;

        // ********************************************************************
        //                         [ PUBLIC METHODS ]
        // ********************************************************************

        public function UpdatablePoint(x:Number=0, y:Number=0)
        {
            super(x, y);
        }

        override public function toString():String
        {
            return "(x=" + super.x + ", y=" + super.y + ", previousX=" +
                _previousX + ", previousY=" + _previousY + ", deltaX=" +
                _deltaX + ", deltaY=" + _deltaY + ")";
        }

        // ********************************************************************
        //                        [ GETTERS / SETTERS ]
        // ********************************************************************

        override public function set x(x:Number):void
        {
            _previousX = super.x;
            super.x = x;
            _deltaX = super.x - _previousX;
        }

        override public function set y(y:Number):void
        {
            _previousY = super.y;
            super.y = y;
            _deltaY = super.y - _previousY;
        }

        public function get previousX():Number
        {
            return _previousX;
        }

        public function get previousY():Number
        {
            return _previousY;
        }

        public function get deltaX():Number
        {
            return _deltaX;
        }

        public function get deltaY():Number
        {
            return _deltaY;
        }
    }
}
+5
2

Point get/set-, : public var x : Number public var y : Number. . .

- , , -, , . , extends Point Point UpdatablePoint. x/y . [X/y] myPointInstance. [X/y].

Point, . , "equals" Point, : return myPointInstance.equals(p);

+5

public function set x public function set y.

, , . , , Adobe , .

+2

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