How to use

mxICellOverlay

in

com.mxgraph.swing.util

/**
 * Notified when an overlay has been removed from the graph. This
 * implementation removes the given overlay from its parent if it is a
 * component inside a component hierarchy.
 */
protected void updateCellOverlayComponent(mxCellState state,
    mxICellOverlay overlay)
{
  if (overlay instanceof Component)
  {
    Component comp = (Component) overlay;
    if (comp.getParent() == null)
    {
      getGraphControl().add(comp, 0);
    }
    mxRectangle rect = overlay.getBounds(state);
    if (rect != null)
    {
      comp.setBounds(rect.getRectangle());
      comp.setVisible(true);
    }
    else
    {
      comp.setVisible(false);
    }
  }
}

/**
 * Notified when an overlay has been removed from the graph. This
 * implementation removes the given overlay from its parent if it is a
 * component inside a component hierarchy.
 */
protected void updateCellOverlayComponent(mxCellState state,
    mxICellOverlay overlay)
{
  if (overlay instanceof Component)
  {
    Component comp = (Component) overlay;
    if (comp.getParent() == null)
    {
      getGraphControl().add(comp, 0);
    }
    mxRectangle rect = overlay.getBounds(state);
    if (rect != null)
    {
      comp.setBounds(rect.getRectangle());
      comp.setVisible(true);
    }
    else
    {
      comp.setVisible(false);
    }
  }
}