Add Item on JComboBox using JTextField

Output:

Code:

/**
 * File: jtextfieldToJComboBox.java
 * Tiltle: Add Item on JComboBox using JTextField
 * Author: http://java-program-sample.blogspot.com
 */
 
//Java Extension Packages
import javax.swing.*;
//Java Core Packages
import java.awt.*;
import java.awt.event.*;

public class jtextfieldToJComboBox extends JFrame {
 
 //Initializing JTextField and JComboBox
 private JComboBox combo;
 private JTextField input;

 //Setting up GUI
 public jtextfieldToJComboBox() {

 //Setting up the Title of the Window
 super("Add Item on JComboBox using JTextField");

 //Set Size of the Window (WIDTH, LENGTH)
 setSize(320,80);

 //Exit Property of the Window
 setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);

 //Constructing JTextField and JComboBox
 input = new JTextField("Type your Input Here and Press Enter");
 combo = new JComboBox();

 //Setting JComboBox Properties
 combo.setMaximumRowCount(5); //Number of Itmes to be displayed. If greater than 5, Vertical ScrollBar will be displayed.

 //Setting up the container ready for the components to be added.
    Container pane = getContentPane();
    setContentPane(pane);
    
    //Setting up the container layout
 GridLayout layout = new GridLayout(2,1);
 pane.setLayout(layout);

 //Implemeting Even-Listener on JTextField's reference name "input" using ActionListener
 input.addActionListener(
  new ActionListener() {
   
   //Handle JTextField event if Enter key is pressed
   public void actionPerformed(ActionEvent event) {
    
    //Store the input from JTextField to the variable "message"
    String message = "The Input <"+input.getText()+"> is Successfully Added!";
    
    //Adding items or elements from JTextField to JComboBox
    combo.addItem(input.getText());
    
    //Display the input from JTextField to JOptionPane using the variable "message"
    JOptionPane.showMessageDialog(null, message,"Successfully Added!",JOptionPane.INFORMATION_MESSAGE);
    
    //The JTextField will be empty after JOptionPane is closed ready for the next input.
    input.setText(null);
   }
  }
  );

 //Adding JTextField and JComboBox in the container
 pane.add(input);
 pane.add(combo);
 
 /**Set all the Components Visible.
    * If it is set to "false", the components in the container will not be visible.
    */
 setVisible(true);
 }
 
 //Main Method
 public static void main(String[] args) {
  jtextfieldToJComboBox jtcb = new jtextfieldToJComboBox();
 }
}

Important Part of the Program:

//Implemeting Even-Listener on JTextField's reference name "input" using ActionListener
 input.addActionListener(
  new ActionListener() {
   
   //Handle JTextField event if Enter key is pressed
   public void actionPerformed(ActionEvent event) {
    
    //Store the input from JTextField to the variable "message"
    String message = "The Input <"+input.getText()+"> is Successfully Added!";
    
    //Adding items or elements from JTextField to JComboBox
    combo.addItem(input.getText());
    
    //Display the input from JTextField to JOptionPane using the variable "message"
    JOptionPane.showMessageDialog(null, message,"Successfully Added!",JOptionPane.INFORMATION_MESSAGE);
    
    //The JTextField will be empty after JOptionPane is closed ready for the next input.
    input.setText(null);
   }
  }
  );

Posted in: JComboBox,JTextField