JComboBoxTest.java

This demo sends messages to the console.

A JComboBox is a component that displays a drop-down list and gives users options that we can select one and only one item at a time whereas a JList shows multiple items (rows) to the user and also gives an option to let the user select multiple items. A JComboBox can be editable or read-only.

Compare to JList

Reference: JComboBox vs JList

`JComboBoxTest.java`

import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
public class JComboBoxTest extends JFrame {
   JComboBoxTest() {
      setTitle("JComboBox Test");
      String devices[] = {"Resistor","Voltage Source","Current Source","Ground"};
      JComboBox<String> jcb = new JComboBox<String>(devices);
      //jcb.setEditable(true);
      //jcb.setSelectedIndex(3);
        jcb.addItemListener(itemEvent -> {
		if (itemEvent.getStateChange()==ItemEvent.SELECTED) {
			int ndx = jcb.getSelectedIndex();
			setTitle(devices[ndx]);
		}
		System.out.println(itemEvent.paramString());
		Object obj = itemEvent.getItem();
		if (obj instanceof String) System.out.println("Object: " + obj);
        });
      setLayout(new FlowLayout());
      add(jcb);
      setSize(300, 250);
      setLocationRelativeTo(null);
      setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
      setVisible(true);
   }
   public static void main(String[] args) {
      new JComboBoxTest();
   }
}

Maintained by John Loomis, updated Fri Apr 03 15:12:17 2020