setStylePrimaryName(tool.getUpStyleName());
addStyleName("transparent-75");
DOM.setStyleAttribute(getElement(), "width", "15px");
DOM.setStyleAttribute(getElement(), "height", "15px");
DOM.setStyleAttribute(getElement(), "cursor", "pointer");
MouseHoverHandler hoverHandler = new MouseHoverHandler() {
@Override
public void onMouseOver(MouseOverEvent event) {
removeStyleName("transparent-75");
}