code: @Override
  	public void doRender(final WComponent component, final WebXmlRenderContext renderContext) {
  		WRow row = (WRow) component;
  		XmlStringBuilder xml = renderContext.getWriter();
  		int cols = row.getChildCount();
  		Size gap = row.getSpace();
  		String gapString = gap != null ? gap.toString() : null;
  
  		if (cols > 0) {
  			xml.appendTagOpen("ui:row");
  			xml.appendAttribute("id", component.getId());
  			xml.appendOptionalAttribute("class", component.getHtmlClass());
  			xml.appendOptionalAttribute("track", component.isTracking(), "true");
  			xml.appendOptionalAttribute("gap", gapString);
  			xml.appendClose();
  
  			// Render margin
  			MarginRendererUtil.renderMargin(row, renderContext);
  
  			paintChildren(row, renderContext);
  
  			xml.appendEndTag("ui:row");
  		}
  	}
docs: Paints the given WButton.
  
  @param component the WRow to paint.
  @param renderContext the RenderContext to paint to.