Java Program to disable the first item on a JComboBox

Java 8Object Oriented ProgrammingProgramming

To disable the first index, on the click of a button, let us implement for index > 0 i.e. item 2:

System.out.println("Index 0 (First Item) is disabled... ");
comboBox.addItemListener(e -> {
   if (comboBox.getSelectedIndex() > 0) {
      System.out.println("Index = " + comboBox.getSelectedIndex());
   }
});

By implementing above, we have disabled the first item.

The following is an example to disable the first item on a JComboBox:

Example

import javax.swing.*;
public class SwingDemo {
   JFrame frame;
   SwingDemo(){
      frame = new JFrame("ComboBox");
      String Sports[]={"Select","Tennis","Cricket","Football"};
      JComboBox comboBox = new JComboBox(Sports);
      comboBox.setBounds(50, 50,90,20);
      frame.add(comboBox);
      frame.setLayout(null);
      frame.setSize(400,500);
      frame.setVisible(true);
      System.out.println("Index 0 (First Item) is disabled... ");
      comboBox.addItemListener(e -> {
         if (comboBox.getSelectedIndex() > 0) {
            System.out.println("Index = " + comboBox.getSelectedIndex());
         }
      });
   }
   public static void main(String[] args) {
      new SwingDemo();
   }
}

The output is as follows. You can now select all the indexes except index 0 (first item). Let us select the first index i.e. the second item:

Output

Meanwhile, while selecting Tennis above, the following is displayed on Console:

raja
Published on 06-May-2019 11:46:54
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