protected int insertPlaceholderAsLastChild(Element placeholder) {

        m_children.getElement().appendChild(placeholder);
        getTree().setPlaceholderPath(getPath());
        return getChildCount();
    }
protected int insertPlaceholderAsLastChild ( Element placeholder ) { m_children . getElement ( ) . appendChild ( placeholder ) ; getTree ( ) . setPlaceholderPath ( getPath ( ) ) ; return getChildCount ( ) ; }
Inserts the placeholder element as last child of the children list.
Setting it's path as the current placeholder path and returning the new index.<p>

@param placeholder the placeholder element

@return the new index