Menu Radio Button Java Example

There are several kinds of buttons in computer applications, buttons that you click on with the mouse pointer or that you activate with a key stroke. Buttons provide a way to tell the computer what to do. The buttons with the little round dots are called radio buttons, and they always come in groups of two or more. A set of radio buttons is a visual clue that you only have a choice of one of those options. Choosing another button automatically turns off the button that was currently selected, just like pressing a button on your car radio switches you from one station to the next.

Like other buttons, radio buttons are mostly found in a graphical user interface like the Macintosh or Windows or Presentation Manager, but they’re popping up in text-mode programs, too. Compare radio buttons with checkbox buttons, where you can choose as many of the checkboxes as you like.

import java.awt.*; 
 import javax.swing.*; 
 import java.awt.event.*; 
 public class JavaExampleMenuRadioButtonInJApplet extends JApplet implements ItemListener 
      { 
         ImageIcon Icn = new ImageIcon("item.jpg"); 
         JRadioButtonMenuItem 
         RdoBtnMnuItem1 = new JRadioButtonMenuItem("Item 1", Icn), 
         RdoBtnMnuItem2 = new JRadioButtonMenuItem("Item 2", Icn), 
         RdoBtnMnuItem3 = new JRadioButtonMenuItem("Item 3", Icn), 
         RdoBtnMnuItem4 = new JRadioButtonMenuItem("Item 4", Icn); 
         public void init() 
          { 
              Container Cntnr = getContentPane(); 
              JMenuBar MnuBar = new JMenuBar(); 
              JMenu Mnu = new JMenu("Radio Button Menu Items"); 
              Mnu.add(RdoBtnMnuItem1); 
              Mnu.add(RdoBtnMnuItem2); 
              Mnu.add(RdoBtnMnuItem3); 
              Mnu.add(RdoBtnMnuItem4); 
              ButtonGroup BtnGrp = new ButtonGroup(); 
              BtnGrp.add(RdoBtnMnuItem1); 
              BtnGrp.add(RdoBtnMnuItem2); 
              BtnGrp.add(RdoBtnMnuItem3); 
              BtnGrp.add(RdoBtnMnuItem4); 
              RdoBtnMnuItem1.addItemListener(this); 
              RdoBtnMnuItem2.addItemListener(this); 
              RdoBtnMnuItem3.addItemListener(this); 
              RdoBtnMnuItem4.addItemListener(this); 
              MnuBar.add(Mnu); 
              setJMenuBar(MnuBar); 
          } 
              public void itemStateChanged(ItemEvent e1) 
               { 
                  JMenuItem MnuItem= (JMenuItem) e1.getSource(); 
                  String ItmTxt = MnuItem.getText(); 
                  if(e1.getStateChange() == ItemEvent.SELECTED) 
                  ItmTxt += " was selected"; 
                  else 
                  ItmTxt += " was deselected"; 
              showStatus(ItmTxt); 
               } 
   } 
 /*<APPLET CODE = JavaExampleMenuRadioButtonInJApplet.class WIDTH = 350 HEIGHT = 280 ></APPLET>*/