Programing exercise

Question

From our previous lessons. Try to convert the simple program in to a GUI program by using labels, text field and buttons.

Program Output

Enter name

Andrea [Enter]

Enter your age

24 [Enter]

Hello Andrea

You are 24 years old

Answer 1

import java.awt.*;

import java.awt.event.*;

import javax.swing.*;

import javax.swing.event.*;

public class Hello extends JPanel {

private JButton cmdButHELLO;

private JLabel jcomp2;

private JTextArea txtName;

private JLabel jcomp4;

private JTextArea txtAge;

private JLabel labelName;

private JLabel labelAge;

public Hello() {

//construct components

cmdButHELLO = new JButton ("SAY HELLO");

jcomp2 = new JLabel ("Input Name");

txtName = new JTextArea (5, 5);

jcomp4 = new JLabel ("Input Age");

txtAge = new JTextArea (5, 5);

labelName = new JLabel ("");

labelAge = new JLabel ("");

//adjust size and set layout

setPreferredSize (new Dimension (352, 146));

setLayout (null);

//add components

add (cmdButHELLO);

add (jcomp2);

add (txtName);

add (jcomp4);

add (txtAge);

add (labelName);

add (labelAge);

cmdButHELLO.addActionListener(

new ActionListener()

{

@Override public void actionPerformed(ActionEvent e)

{

labelName.setText("Hello " + txtName.getText());

labelAge.setText("You are " + txtAge.getText() + " years old ");

}

}

);

//set component bounds (only needed by Absolute Positioning)

cmdButHELLO.setBounds (245, 30, 105, 35);

jcomp2.setBounds (15, 15, 70, 25);

txtName.setBounds (90, 10, 145, 35);

jcomp4.setBounds (15, 55, 65, 25);

txtAge.setBounds (90, 50, 145, 30);

labelName.setBounds (20, 100, 150, 30);

labelAge.setBounds (200, 100, 150, 25);

}

public static void main (String[] args) {

JFrame frame = new JFrame ("Hello");

frame.setDefaultCloseOperation (JFrame.EXIT_ON_CLOSE);

frame.getContentPane().add (new Hello());

frame.pack();

frame.setVisible (true);

}

}