code: public void onResize(int width, int height) {
  		// Center the line in the shell
  		int lineWidth = lineElement.getOffsetWidth();
  		lineLeftOffset = (width / 2) - (lineWidth / 2);
  		DOM.setStyleAttribute(lineElement, "left", lineLeftOffset + "px");
  
  		// Draw the other components
  		drawLabels();
  		drawTicks();
  		drawKnob();
  	}
docs: This method is called when the dimensions of the parent element change. Subclasses should override this method as
  needed.
  
  @param width
  the new client width of the element
  @param height
  the new client height of the element