function ObjScroller (strScrollThumb,strScrollBar,strScrollUpArrow,strScrollDownArrow){

this.lThumb = new ObjLayer ("",strScrollThumb,"")
this.lBar = new ObjLayer ("",strScrollBar,"")
this.lUpArrow = new ObjLayer ("",strScrollUpArrow,"")
this.lDownArrow = new ObjLayer ("",strScrollDownArrow,"")

this.show = function (objLayer, pintHeightClip) {
	this.lThumb.show();
	this.lBar.show();
	this.lUpArrow.show();
	this.lDownArrow.show();
	this.positionThumb(objLayer, pintHeightClip);
}

this.hide = function () {
	this.lThumb.hide();
	this.lBar.hide();
	this.lUpArrow.hide();
	this.lDownArrow.hide();
}

this.positionThumb = function (objLayer, pintHeightClip) {
	intHeightLayer = objLayer.getHeight();
	intHeightClip = pintHeightClip;
	intPosCursor = objLayer.getClipArea()[0];
	intHeightScrollBar = this.lBar.getHeight();
	intHeightScrollThumb = this.lThumb.getHeight();
	intTopScrollBar = this.lBar.getY();
	intPosThumb = intTopScrollBar + Math.round(intPosCursor*(intHeightScrollBar-intHeightScrollThumb)/(intHeightLayer-intHeightClip));
	this.lThumb.setY(intPosThumb);
}
}