var DragScrollable=Class.create();DragScrollable.prototype={initialize:function(element){this.element=$(element);this.active=false;this.scrolling=false;this.element.style.cursor='pointer';this.eventMouseDown=this.startScroll.bindAsEventListener(this);this.eventMouseUp=this.endScroll.bindAsEventListener(this);this.eventMouseMove=this.scroll.bindAsEventListener(this);Event.observe(this.element,'mousedown',this.eventMouseDown);},destroy:function(){Event.stopObserving(this.element,'mousedown',this.eventMouseDown);Event.stopObserving(document,'mouseup',this.eventMouseUp);Event.stopObserving(document,'mousemove',this.eventMouseMove);},startScroll:function(event){this.startX=Event.pointerX(event);this.startY=Event.pointerY(event);if(Event.isLeftClick(event)){this.element.style.cursor='move';Event.observe(document,'mouseup',this.eventMouseUp);Event.observe(document,'mousemove',this.eventMouseMove);this.active=true;Event.stop(event);}},endScroll:function(event){this.element.style.cursor='pointer';this.active=false;Event.stopObserving(document,'mouseup',this.eventMouseUp);Event.stopObserving(document,'mousemove',this.eventMouseMove);Event.stop(event);},scroll:function(event){if(this.active){this.element.scrollTop+=(this.startY-Event.pointerY(event));this.element.scrollLeft+=(this.startX-Event.pointerX(event));this.startX=Event.pointerX(event);this.startY=Event.pointerY(event);}
Event.stop(event);}}