deserialize method

Implementation

@override
void deserialize(XmlElement xml) {
  // deserialize
  super.deserialize(xml);

  // allow mouse drag
  allowDrag = Xml.get(node: xml, tag: 'allowDrag');

  // clear items
  for (var item in items) {
    item.dispose();
  }
  items.clear();

  // build menu items
  _buildItems();
}