Simple Java Swing Example with JFrame Parent Class

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Java Swing Tutorial

Java Swing tutorial is a part of Java Foundation Classes (JFC) that is used to create window-based applications. It is built on the top of AWT (Abstract Windowing Toolkit) API and entirely written in java.

Package required

javax.swing

Difference between AWT and Swing

JFC

The Java Foundation Classes (JFC) are a set of GUI components which simplify the development of desktop applications.

Commonly used Methods of Component class

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Simple Java Swing Example with JFrame Parent Class

import javax.swing.*;

public class Simple2 extends JFrame{//inheriting JFrame JFrame f;

Simple2(){

JButton b=new JButton("click");//create button b.setBounds(130,100,100, 40);

add(b);//adding button on frame setSize(400,500);

setLayout(null); setVisible(true); }

public static void main(String[] args) { new Simple2();

}}

JButton

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Java JButton Example with ActionListener

import java.awt.event.*; import javax.swing.*;

public class ButtonExample extends JFrame implements ActionListener {

JTextField tf; JButton b; ButtonExample() {

tf=new JTextField();

tf.setBounds(50,50, 150,20); b=new JButton("Click Here"); b.setBounds(50,100,95,30); b.addActionListener(this); add(b);

add(tf); }

public static void main(String[] args) {

ButtonExample f=new ButtonExample();

f.setSize(400,400); f.setLayout(null); f.setVisible(true); }

public void actionPerformed(ActionEvent e) {

tf.setText("Welcome to DIT"); }

}

Example of displaying image on the button:

public class ButtonExample extends JFrame implements ActionListener {

JTextField tf; JButton b, b1; ButtonExample() {

tf=new JTextField();

tf.setBounds(50,50, 150,20); b=new JButton("Click Here");

b1=new JButton(new ImageIcon("D:\\dit notes\\core java\\unit-1 programs\\swings\\index.png")); b.setBounds(50,100,95,30);

b.addActionListener(this); b1.setBounds(50,150,95,30); b1.addActionListener(this); add(b);

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}

ButtonExample f=new ButtonExample();

if(e.getSource()==b) {

tf.setText("Welcome to DIT"); }

else

tf.setText("Welcome to DIT image"); }

}

Java JLabel

The object of JLabel class is a component for placing text in a container. It is used to display a single line of read only text.

Example JLabel l1,l2;

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Java JTextField

The object of a JTextField class is a text component that allows the editing of a single line text. It inherits JTextComponent class.

Example

JTextField t1,t2;

t1=new JTextField("Welcome to Javatpoint."); t1.setBounds(50,100, 200,30);

t2=new JTextField("AWT Tutorial");

t2.setBounds(50,150, 200,30);

JFrame to add two numbers

public class add extends JFrame implements ActionListener {

JLabel l1,l2,l3; JTextField t1, t2,t3; JButton b1, b2; add()

{

l1=new JLabel("First Number"); l2=new JLabel("Second Number"); l3=new JLabel("Result Number"); t1=new JTextField();

t2=new JTextField(); t3=new JTextField(); l1.setBounds(50,50,150,20); t1.setBounds(150,50, 150,20);

l2.setBounds(50,100,150,20); t2.setBounds(150,100, 150,20);

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t3.setBounds(150,150, 150,20); b1=new JButton("Sum");

b2=new JButton("clear"); b1.setBounds(100,200,95,30); b1.addActionListener(this);

b2.setBounds(200,200,95,30); b2.addActionListener(this); add(b1);

add(b2); add(t1); add(t2); add(t3); add(l1); add(l2);

add(l3); }

add f=new add();

if(e.getSource()==b1) {

int a=Integer.parseInt(t1.getText()); int b=Integer.parseInt(t2.getText()); int c=a+b;

t3.setText(Integer.toString(c)); }

t2.setText(" "); t1.setText(" "); t3.setText(" "); }

}

Java JTextArea

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Example

JTextArea area=new JTextArea("Welcome to javatpoint"); area.setBounds(10,30, 200,200);

Count Number of words and characters in TextArea()

public class textarea extends JFrame implements ActionListener {

JLabel l1,l2; JTextArea area; JButton b1; textarea() {

l1=new JLabel();

l1.setBounds(50,25,100,30); l2=new JLabel();

l2.setBounds(160,25,100,30); area=new JTextArea();

area.setBounds(20,75,250,200);

b1=new JButton("Count Words and characters"); b1.setBounds(100,300,120,30);

b1.addActionListener(this); add(l1);

add(l2); add(area); add(b1);

}

textarea f=new textarea ();

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f.setVisible(true); }

String text=area.getText(); String words[]=text.split("\\s"); l1.setText("Words: "+words.length); l2.setText("Characters: "+text.length()); }

}

JOptionPane

he JOptionPane class is used to provide standard dialog boxes such as message dialog box, confirm dialog box and input dialog box. These dialog boxes are used to display information or get input from the user.

There are various types of

Optionpanes-1. Message dialog box – used to display simple messages.

Example

- JOptionPane.showMessageDialog(frameobject,"Hello, Welcome to Javatpoint.");



JOptionPane.showMessageDialog(f,"Successfully Updated.","Alert",JOptionPane.WARNING_MESS AGE);

2. Input Dialog Box - It is used to take input value from user.

Example

-String name=JOptionPane.showInputDialog(f,"Enter Name");

3. Confirmation Dialog Box – It is used when user want to execute some code on pressing of any button.

Example – Do you wish to continue?

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Java JPasswordField

The object of a JPasswordField class is a text component specialized for password entry.

User login form

public class jpassword extends JFrame implements ActionListener {

JLabel l1,l2; JTextField t1; JButton b1, b2; JPasswordField tp; jpassword() {

l1=new JLabel("Username"); l2=new JLabel("Password");

t1=new JTextField(); tp=new JPasswordField(); l1.setBounds(50,50,150,20); t1.setBounds(150,50, 150,20);

l2.setBounds(50,100,150,20); tp.setBounds(150,100, 150,20);

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b1.setBounds(100,200,95,30); b1.addActionListener(this);

b2.setBounds(200,200,95,30); b2.addActionListener(this); add(b1);

add(b2); add(t1); add(tp); add(l1); add(l2); }

jpassword f=new jpassword();

String u=t1.getText();

String p=tp.getText();

if(u.equals("dit") && p.equals("123")) {

JOptionPane.showMessageDialog(this,"Correct Login"); }

}

t1.setText(" "); tp.setText(" ");

} }

}

Java JCheckBox

The JCheckBox class is used to create a checkbox. It is used to turn an option on (true) or off (false). Clicking on a CheckBox changes its state from "on" to "off" or from "off" to "on "

Java JCheckBox Example with ItemListener

import javax.swing.*; import java.awt.event.*;

public class Checkbox extends JFrame implements ActionListener {

JLabel l;

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Checkbox() {

l=new JLabel("Food Ordering System"); l.setBounds(50,50,300,20);

cb1=new JCheckBox("Pizza @ 100"); cb1.setBounds(100,100,150,20); cb2=new JCheckBox("Burger @ 30"); cb2.setBounds(100,150,150,20); cb3=new JCheckBox("Tea @ 10"); cb3.setBounds(100,200,150,20); b=new JButton("Order");

b.setBounds(100,250,80,30); b.addActionListener(this);

add(l);add(cb1);add(cb2);add(cb3);add(b); setSize(400,400);

setLayout(null); setVisible(true);

setDefaultCloseOperation(EXIT_ON_CLOSE); }

float amount=0; String msg=""; if(cb1.isSelected()){ amount+=100; msg="Pizza: 100\n"; }

if(cb2.isSelected()){ amount+=30;

msg+="Burger: 30\n"; }

if(cb3.isSelected()){ amount+=10; msg+="Tea: 10\n"; }

msg+="---\n";

JOptionPane.showMessageDialog(this,msg+"Total: "+amount); }

Checkbox c1=new Checkbox(); }

}

Java JRadioButton

The JRadioButton class is used to create a radio button. It is used to choose one option from multiple options. It is widely used in exam systems or quiz.

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class Radiobut extends JFrame implements ActionListener { JRadioButton rb1,rb2; JButton b; Radiobut() { rb1=new JRadioButton("Male"); rb1.setBounds(100,50,100,30); rb2=new JRadioButton("Female"); rb2.setBounds(100,100,100,30); ButtonGroup bg=new ButtonGroup(); bg.add(rb1);bg.add(rb2); b=new JButton("click"); b.setBounds(100,150,80,30); b.addActionListener(this); add(rb1); add(rb2); add(b); setSize(300,300); setLayout(null); setVisible(true); setDefaultCloseOperation(EXIT_ON_CLOSE); }

if(rb1.isSelected()) {

JOptionPane.showMessageDialog(this,"You are Male."); }

if(rb2.isSelected()) {

JOptionPane.showMessageDialog(this,"You are Female."); }

}

public static void main(String args[]) {

Radiobut rb=new Radiobut(); }

}

Java JComboBox

The object of Choice class is used to show popup menu of choices. Choice selected by user is shown on the top of a menu.

Example – Choose language to study

public class Combobox extends JFrame implements ActionListener {

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JButton b;

Combobox() {

label = new JLabel();

label.setHorizontalAlignment(JLabel.CENTER); label.setSize(400,100);

b=new JButton("Show"); b.setBounds(200,100,75,20);

String languages[]={"C","C++","C#","Java","PHP"}; cb=new JComboBox(languages);

cb.setBounds(50, 100,90,20); add(cb);

add(label); add(b);

setLayout(null); setSize(350,350); setVisible(true); b.addActionListener(this); }

String data = "Programming language Selected: "+ cb.getItemAt(cb.getSelectedIndex()); label.setText(data);

}

public static void main(String[] args) { Combobox c1=new Combobox(); }