flash on 2010-6-22

/**
 * Copyright gs1mm0ns ( http://wonderfl.net/user/gs1mm0ns )
 * MIT License ( http://www.opensource.org/licenses/mit-license.php )
 * Downloaded from: http://wonderfl.net/c/xdBM
 */

package
{
    
    import flash.display.Shape;
    import flash.events.Event;
    import flash.events.MouseEvent;
    
    public class MovingCircle extends Shape
    {
        
        public var xspeed:Number;
        public var yspeed:Number;
        
        public function MovingCircle ( )
        {
            
            // graphics is an inherited property from Shape
            
            graphics.beginFill( 0xff9933, 1 );            
            graphics.drawCircle( 0 , 0 , 40 );    
            
        }
        
        // initialization, called after parent addChild
        
        public function init ( ):void                    
        {
            
            // x , y and stage are inherited properties
            
            x = Math.random( ) * ( stage.stageWidth );        
            y = Math.random( ) * ( stage.stageHeight );
            
            xspeed = Math.random( ) * 10;
            yspeed = Math.random( ) * 10;
            
            // start step triggering function based on enterframe event
            
            addEventListener( MouseEvent.MOUSE_DOWN , step );    
            
        }
        
        public function step ( event:Event ):void
        {
            
            // bounce ball at stage edges
            
            if ( x + xspeed > stage.stageWidth ) xspeed *= -1;
            else if ( x + xspeed < 0 ) xspeed *= -1;
            
            if ( y + yspeed > stage.stageHeight ) yspeed *= -1;
            else if ( y + yspeed < 0 ) yspeed *= -1;
            
            // set position
            
            x += xspeed;
            y += yspeed;
            
        }
        
    }
 }