docs: public JPanel addToolbar(JComponent screen, JComponent toolbar)
      {
          JPanel panelMain = new JPanel();
          panelMain.setOpaque(false);
          panelMain.setLayout(new BoxLayout(panelMain, BoxLayout.Y_AXIS));
          panelMain.add(toolbar);
          toolbar.setAlignmentX(0);
          panelMain.add(screen);
          screen.setAlignmentX(0);
          return panelMain;
      }