show();
setVisible(true);
   void butFlip_actionPerformed(ActionEvent e) {      flip = !flip;      if (startColor == color1) {         startColor = color2;         endColor = color1;      } else {         startColor = color1;         endColor = color2;      }      heightLabel1.setForeground(startColor);      heightLabel2.setForeground(endColor);      setText();      show();      bv.drawRuler(start, end, startColor, endColor);   }