String[] options = new String[] {"Choose A Percentage", "Choose A Number"};
            int response = JOptionPane.showOptionDialog(null, panel, "Label",
            JOptionPane.DEFAULT_OPTION, JOptionPane.PLAIN_MESSAGE, null, options, options[0]);

            if (response == 0) {
                System.out.println("0");
            } else {
                System.out.println("1");
            }