Show an desktop menu bar

thanks, but here ( Raspberry Pi ) i must use

//    frame = (JFrame) (processing.awt.PSurfaceAWT.SmoothCanvas)app.getSurface().getNative()).getFrame();
    frame = (JFrame) ((processing.awt.PSurfaceAWT.SmoothCanvas)app.getSurface().getNative()).getFrame();

and in setup to see something, like

void setup() {
  size(500,500);
  buildMenuBar();
}

2019-03-27_00-04-50_snap