group = doc.createElementNS("http://www.w3.org/2000/svg", "g");
group.setAttributeNS(null, "id", getLayerId());
if (isAddOpacity()) {
group.setAttributeNS(null, "style", "opacity:" + getOpacity());
}
group.appendChild(getBoxDefinition(doc));
group.appendChild(getImageDefinition(doc));
group.appendChild(getStartImageText(doc));
// Process Sub Activities
group.appendChild(getSubActivitiesSVGString(doc));
//Add Arrow