Develop Reference

How do you close a JFrame window without closing another one?

I am new to Java Swing and I am trying to learn how to close one frame without closing the other one using button. For example I have a frame1/window that just have a button called login. Once I click on login button, another window appear frame2. On frame2 I just have a sample JLabel "Hello And Welcome", button called Logout. I want to be able to click on the Logout button on frame2 and frame2 window should close, but frame1 window show still be open. I have try setDefaultCloseOperation(JFrame.DISPOSE_ON_CLOSE), but it only work if I click on the x icon on the top right of the frame2 window. Does anyone know of a way to close a frame when you click on a button?
public class Frame1 extends JFrame implements ActionListener{
private static JButton login = new JButton("Login");
private static JFrame f = new JFrame("Login");
Frame1(){
f.setSize(1000,750);
f.setLocation(750, 250);
login.setBounds(250, 350, 150, 30);
f.add(login);
f.setLayout(null);
f.setVisible(true);
login.addActionListener(this);
f.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
}
public void actionPerformed(ActionEvent e){
if (e.getSource() == login){
Frame2.frame2windown();
}
}
public static void main(String [] args){
Frame1 login1 = new Frame1();
}
}
public class Frame2 extends JFrame implements ActionListener{
private static JButton logout = new JButton("Logout");
private static JLabel jb1 = new JLabel ("Hello And Welcome");
private static JFrame f = new JFrame("Log Out");
Frame2(){
f.setSize(1000,750);
f.setLocation(750, 250);
jb1.setBounds(250, 150, 350, 30);
logout.setBounds(250, 350, 150, 30);
f.add(logout);
f.add(jb1);
f.setLayout(null);
f.setVisible(true);
logout.addActionListener(this);
f.setDefaultCloseOperation(JFrame.DISPOSE_ON_CLOSE);
}
public void actionPerformed(ActionEvent a){
if(a.getSource() == logout){
dispose();
WindowEvent closeWindow = new WindowEvent(this, JFrame.DISPOSE_ON_CLOSE);
Toolkit.getDefaultToolkit().getSystemEventQueue().postEvent(closeWindow);
}
}
public static void frame2windown(){
Frame2 f2 = new Frame2();
}
}

So, there are a whole bunch of concepts your need to try and learn.
It's generally recommended NOT to extend from top level containers (like JFrame). You're not adding any new functionality too them; they are complicated, compound components; you lock yourself into a single use case (what happens if you want to include the UI in another UI or use a dialog instead of frame?!)
Multiple frames aren't always a good idea and can be confusing to the user. Generally, with login workflows though, I might argue a login dialog is generally a better solution, but you need to understand the use cases to make those determinations.
Swing is a large, rich and diverse API, it has a LOT of inbuilt functionality, which you can use, to make your life easier (although it doesn't always seem this way)
Layout managers are an absolutely required feature and you really need to take the time to learn them, see Laying Out Components Within a Container for more details.
So, a really quick example of using a CardLayout and a basic "observer pattern", which decouples and separates responsibility.
import java.awt.CardLayout;
import java.awt.EventQueue;
import java.awt.GridBagLayout;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.util.EventListener;
import java.util.Random;
import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JOptionPane;
import javax.swing.JPanel;
import javax.swing.border.EmptyBorder;
public class Test {
public static void main(String[] args) {
new Test();
}
public Test() {
EventQueue.invokeLater(new Runnable() {
#Override
public void run() {
JFrame frame = new JFrame();
frame.add(new NavigationPane());
frame.pack();
frame.setLocationRelativeTo(null);
frame.setVisible(true);
}
});
}
public static class NavigationPane extends JPanel {
protected enum NavigationTarget {
LOGIN, MAIN;
}
private LoginPane loginPane;
private MainPane mainPane;
private CardLayout cardLayout;
public NavigationPane() {
cardLayout = new CardLayout();
setLayout(cardLayout);
loginPane = new LoginPane();
loginPane.addLoginListener(new LoginPane.LoginListener() {
#Override
public void loginDidFail(LoginPane source) {
JOptionPane.showMessageDialog(NavigationPane.this, "You are not unauthroised", "Error", JOptionPane.ERROR_MESSAGE);
}
#Override
public void loginWasSuccessful(LoginPane source) {
navigateTo(NavigationTarget.MAIN);
}
});
mainPane = new MainPane();
add(loginPane, NavigationTarget.LOGIN.name());
add(mainPane, NavigationTarget.MAIN.name());
navigateTo(NavigationTarget.LOGIN);
}
protected void navigateTo(NavigationTarget target) {
cardLayout.show(this, target.name());
}
}
public static class LoginPane extends JPanel {
public static interface LoginListener extends EventListener {
public void loginDidFail(LoginPane source);
public void loginWasSuccessful(LoginPane source);
}
public LoginPane() {
setBorder(new EmptyBorder(10, 10, 10, 10));
setLayout(new GridBagLayout());
JButton btn = new JButton("Login");
btn.addActionListener(new ActionListener() {
private Random rnd = new Random();
#Override
public void actionPerformed(ActionEvent e) {
// Do some logic here
if (rnd.nextBoolean()) {
fireLoginWasSuccessful();
} else {
fireLoginDidFail();
}
}
});
add(btn);
}
public void addLoginListener(LoginListener listener) {
listenerList.add(LoginListener.class, listener);
}
public void removeLoginListener(LoginListener listener) {
listenerList.remove(LoginListener.class, listener);
}
protected void fireLoginDidFail() {
LoginListener[] listeners = listenerList.getListeners(LoginListener.class);
for (LoginListener listener : listeners) {
listener.loginDidFail(this);
}
}
protected void fireLoginWasSuccessful() {
LoginListener[] listeners = listenerList.getListeners(LoginListener.class);
for (LoginListener listener : listeners) {
listener.loginWasSuccessful(this);
}
}
}
public static class MainPane extends JPanel {
public MainPane() {
setLayout(new GridBagLayout());
setBorder(new EmptyBorder(10, 10, 10, 10));
add(new JLabel("Welcome"));
}
}
}
JDialog based login workflow
import java.awt.BorderLayout;
import java.awt.CardLayout;
import java.awt.Component;
import java.awt.EventQueue;
import java.awt.GridBagLayout;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.util.Random;
import javax.swing.JButton;
import javax.swing.JDialog;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JOptionPane;
import javax.swing.JPanel;
import javax.swing.SwingUtilities;
import javax.swing.border.EmptyBorder;
public class Test {
public static void main(String[] args) {
new Test();
}
public Test() {
EventQueue.invokeLater(new Runnable() {
#Override
public void run() {
NavigationPane navigationPane = new NavigationPane();
JFrame frame = new JFrame();
frame.add(navigationPane);
frame.pack();
frame.setLocationRelativeTo(null);
frame.setVisible(true);
if (LoginPane.showLoginDialog(navigationPane)) {
navigationPane.didLogin();
} else {
frame.dispose();
}
}
});
}
public static class NavigationPane extends JPanel {
protected enum NavigationTarget {
SPLASH, MAIN;
}
private SplashPane splashPane;
private MainPane mainPane;
private CardLayout cardLayout;
public NavigationPane() {
cardLayout = new CardLayout();
setLayout(cardLayout);
mainPane = new MainPane();
splashPane = new SplashPane();
add(splashPane, NavigationTarget.SPLASH.name());
add(mainPane, NavigationTarget.MAIN.name());
navigateTo(NavigationTarget.SPLASH);
}
protected void navigateTo(NavigationTarget target) {
cardLayout.show(this, target.name());
}
public void didLogin() {
navigateTo(NavigationTarget.MAIN);
}
}
public static class LoginPane extends JPanel {
private Random rnd = new Random();
private boolean isAuthorised = false;
public LoginPane() {
setBorder(new EmptyBorder(10, 10, 10, 10));
setLayout(new GridBagLayout());
add(new JLabel("User name and password fields go here"));
}
protected void authenticate() {
// Authenticate
isAuthorised = rnd.nextBoolean();
if (!isAuthorised) {
JOptionPane.showMessageDialog(this, "You are not authorised", "Error", JOptionPane.ERROR_MESSAGE);
}
}
// So this should return some kind of "session" or something so
// can identify the user, but for now, we'll just use
// a boolean
public boolean isAuthorised() {
return isAuthorised;
}
public static boolean showLoginDialog(Component parent) {
LoginPane loginPane = new LoginPane();
JPanel panel = new JPanel(new BorderLayout());
JPanel buttonPane = new JPanel(new GridBagLayout());
JButton okayButton = new JButton("Login");
JButton cancelButton = new JButton("Cancel");
buttonPane.add(okayButton);
buttonPane.add(cancelButton);
panel.add(loginPane);
panel.add(buttonPane, BorderLayout.SOUTH);
JDialog dialog = new JDialog(SwingUtilities.windowForComponent(parent));
dialog.add(panel);
okayButton.addActionListener(new ActionListener() {
#Override
public void actionPerformed(ActionEvent e) {
loginPane.authenticate();
if (loginPane.isAuthorised()) {
dialog.dispose();
}
}
});
cancelButton.addActionListener(new ActionListener() {
#Override
public void actionPerformed(ActionEvent e) {
dialog.dispose();
}
});
dialog.setModal(true);
dialog.pack();
dialog.setLocationRelativeTo(parent);
dialog.setVisible(true);
return loginPane.isAuthorised();
}
}
public static class SplashPane extends JPanel {
public SplashPane() {
setLayout(new GridBagLayout());
setBorder(new EmptyBorder(10, 10, 10, 10));
add(new JLabel("This is a splash panel, put some nice graphics here"));
}
}
public static class MainPane extends JPanel {
public MainPane() {
setLayout(new GridBagLayout());
setBorder(new EmptyBorder(10, 10, 10, 10));
add(new JLabel("Welcome"));
}
}
}

You duplicated the JFrame, created a JFrame field f inside the JFrame.
Do not use static components like the button.
public class Frame1 extends JFrame implements ActionListener {
private final JButton login = new JButton("Login");
Frame1() {
setTitle("Login");
setSize(1000, 750);
setLocation(750, 250);
setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
setLayout(null);
login.setBounds(250, 350, 150, 30);
add(login);
login.addActionListener(this);
setVisible(true);
}
public void actionPerformed(ActionEvent e) {
if (e.getSource() == login) {
Frame2.frame2windown();
}
}
public static void main(String[] args) {
EventQueue.invokeLater(() -> {
Frame1 login1 = new Frame1();
}
}
}
Use the swing/awt event queue (invokeLater) as on this thread window events are handled and dispatched further.
And Frame2:
public class Frame2 extends JFrame implements ActionListener {
private JButton logout = new JButton("Logout");
private JLabel jb1 = new JLabel("Hello And Welcome");
Frame2() {
setTitle("Logout");
setSize(1000, 750);
setLocation(750, 250);
setLayout(null);
setDefaultCloseOperation(JFrame.DISPOSE_ON_CLOSE);
jb1.setBounds(250, 150, 350, 30);
logout.setBounds(250, 350, 150, 30);
add(logout);
add(jb1);
logout.addActionListener(this);
setVisible(true);
}
public void actionPerformed(ActionEvent a) {
if (a.getSource() == logout) {
setVisible(false); // <--- ALL
}
}
public static void frame2windown() {
Frame2 f2 = new Frame2();
}
}
JFrame.setVisible does it all. Especially setVisible(true) should maybe even done after the constructor is called, so it always is last.
Another remark, dive into layout managers fast. Absolute layouts (null) are a PITA.

Importing button and text field from another class to main class

I have two different classes (mainClass) and (visual). In the visual class I have a method and inside the method I put the required code for a simple JButton. In the main class I create an object to call the method from visual class, to show the button in the main class . But it does not work. I would appreciate any advice.
package init;
import java.awt.EventQueue;
import javax.swing.JFrame;
import javax.swing.JButton;
public class mainClass {
private JFrame frame;
/**
* Launch the application.
*/
public static void main(String[] args) {
EventQueue.invokeLater(new Runnable() {
public void run() {
try {
mainClass window = new mainClass();
window.frame.setVisible(true);
} catch (Exception e) {
e.printStackTrace();
}
}
});
}
/**
* Create the application.
*/
public mainClass() {
initialize();
}
/**
* Initialize the contents of the frame.
*/
private void initialize() {
frame = new JFrame();
frame.setBounds(100, 100, 450, 300);
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.getContentPane().setLayout(null);
In the code below I made an object and called the method from the visual class
visual bt = new visual();
bt.btn();
}
}
////////////////VISUAL CLASS//////////////////////
package init;
import javax.swing.JButton;
import javax.swing.JFrame;
public class visual {
public JFrame frame;
public void btn() {
JButton btnNewButton = new JButton("New button");
btnNewButton.setBounds(141, 155, 151, 45);
frame.getContentPane().add(btnNewButton);
}
}

For what you are trying to achieve here you don't need 2 classes. You can do it like this:
import javax.swing.*;
import java.awt.*;
public class MainClass {
/**
* Launch the application.
*/
public static void main(String[] args) {
EventQueue.invokeLater(new Runnable() {
public void run() {
try {
JFrame frame = new JFrame();
frame.setBounds(100, 100, 450, 300);
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
JButton btnNewButton = new JButton("New button");
frame.getContentPane().setLayout(new FlowLayout());
frame.getContentPane().add(btnNewButton);
frame.setVisible(true);
} catch (Exception e) {
e.printStackTrace();
}
}
});
}
}

I can't change the color of a JButton when pressed

I have all the imports needed and there are no errors but it won't work.
final JButton button_32 = new JButton("2");
button_32.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent e) {
button_32.setBackground(Color.red);
}
});
button_32.setBounds(0, 57, 33, 29);
contentPane.add(button_32);

You can create your own Button, which extends ButtonModel or just do it, as suggested here.

public class Main {
static JFrame frame;
public static void main(String[] args)
{
// schedule this for the event dispatch thread (edt)
SwingUtilities.invokeLater(new Runnable()
{
public void run()
{
displayJFrame();
}
});
}
static void displayJFrame()
{
frame = new JFrame("Our JButton listener example");
// create our jbutton
final JButton showDialogButton = new JButton("Click Me");
// add the listener to the jbutton to handle the "pressed" event
showDialogButton.addActionListener(new ActionListener()
{
public void actionPerformed(ActionEvent e)
{
// when the button is pressed
showDialogButton.setBackground(Color.RED);
}
});
// put the button on the frame
frame.getContentPane().setLayout(new FlowLayout());
frame.add(showDialogButton);
// set up the jframe, then display it
frame.setDefaultCloseOperation(WindowConstants.EXIT_ON_CLOSE);
frame.setPreferredSize(new Dimension(300, 200));
frame.pack();
frame.setLocationRelativeTo(null);
frame.setVisible(true);
}
}

I think it can be related to "implementation of the abstract class".
Try this:
import java.awt.BorderLayout;
import java.awt.Color;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import javax.swing.JButton;
import javax.swing.JFrame;
public class ExamButton extends JFrame {
JButton button_32 = new JButton("ssf");
JFrame frame = new JFrame();
public ExamButton() {
final JButton button_32 = new JButton("2");
button_32.addActionListener(new ActionListener() {
#Override
public void actionPerformed(ActionEvent ae) {
button_32.setBackground(Color.red);
}
});
button_32.setBounds(0, 57, 33, 29);
add(button_32, BorderLayout.CENTER);
setSize(300, 300);
setVisible(true);
}
public static void main(String[] args) {
new ExamButton();
}
}

java - method and passing variable from jInternalFrame to jFrame

and I have the following problem.
i am new in java and i am trying to send a variable which is user_id, from JInternalFrame to JFrame.
I can't use constructor because JFrame is the main program activated at startup and containing jDesktoPane
so i was trying to use the methods, however, can't do it (i posted the two methods, both of which I tried but did not work)
Method A)
Code in jFrame (Main_window)
public javax.swing.JTextField getID() {
return jTextField_id;
}
public void setID(javax.swing.JTextField ID)
{
jTextField_id = ID;
}
code in jInternalFrame
Main_window send = new Main_window();
send.getID().setText("123");
Method B)
Code in jFrame (Main_window)
USER_ID is a variable accesible in any place of jFrame
public void setID(String ID)
{
USER_ID = ID;
}
code in jInternalFrame
Main_window send = new Main_window();
send.setID("123");
both method don't change anything but have no errors in compilation
if there is any other way of doing it pls tell me :)
sorry for my language and grammar.
if this help i use Eclipse compilator
this code worked for me, ty for help
public void set_ID(String ID)
{
Test_JF mainWindow = (Test_JF) this.getTopLevelAncestor();;
mainWindow.setID(ID);
}
activated by set_ID("1234");

Try this in your JInternalFrame class:
JFrame mainWindow = (JFrame)this.getTopLevelAncestor();
mainWindow.setID("123");

ok so here is smaller version of my program
"Test_JF" is a main JFrame and "Test_JIF" is a JInternalFrame
here is TestJF
public class Test_JF extends JFrame {
private JPanel contentPane;
private JTextField user_id;
String USER_ID;
public static void main(String[] args) {
EventQueue.invokeLater(new Runnable() {
public void run() {
try {
Test_JF frame = new Test_JF();
frame.setVisible(true);
} catch (Exception e) {
e.printStackTrace();
}
}
});
}
public Test_JF() {
setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
setBounds(100, 100, 750, 500);
contentPane = new JPanel();
contentPane.setBorder(new EmptyBorder(5, 5, 5, 5));
setContentPane(contentPane);
contentPane.setLayout(null);
user_id = new JTextField();
user_id.setBounds(338, 11, 86, 20);
contentPane.add(user_id);
user_id.setColumns(10);
JButton button_user_id = new JButton("fill user id");
button_user_id.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent e) {
user_id.setText(USER_ID);
}
});
button_user_id.setBounds(239, 10, 89, 23);
contentPane.add(button_user_id);
JDesktopPane desktopPane = new JDesktopPane();
desktopPane.setBounds(10, 56, 714, 395);
contentPane.add(desktopPane);
addWindowListener(new WindowAdapter() {
#Override
public void windowOpened(WindowEvent arg0) {
Test_JIF Open = new Test_JIF();
desktopPane.add(Open);
Open.show();
}
});
}
public void setID(String ID)
{
USER_ID = ID;
}}
here is TestJIF
public class Test_JIF extends JInternalFrame {
public static void main(String[] args) {
EventQueue.invokeLater(new Runnable() {
public void run() {
try {
Test_JIF frame = new Test_JIF();
frame.setVisible(true);
} catch (Exception e) {
e.printStackTrace();
}
}
});
}
public Test_JIF() {
Test_JF mainWindow = (Test_JF)this.getTopLevelAncestor();
setBounds(100, 100, 328, 199);
getContentPane().setLayout(null);
JButton button_send = new JButton("New button");
button_send.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent e) {
mainWindow.setID("123");
}
});
button_send.setBounds(111, 73, 89, 23);
getContentPane().add(button_send);
}}
i clear imports here(on web) so it will be cleaner

why does my button not appear on my JPanel - Java

Or maybe my JPanel is not appearing at all.
I am trying to have a JPanel at the bottom of the screen that hold several buttons. Can someone set me strait?
public class MyAWTMenu extends java.awt.Frame// implements ActionListener
{
public void init() {
setBackground( Color.white );
JPanel bottom = new JPanel();
bottom.setBackground(Color.BLACK);
JButton b1 = new JButton("test");
b1.setVisible(true);
bottom.add(b1);
bottom.setVisible(true);
add(bottom,BorderLayout.CENTER);
}
public static void main( String args [] ) {
MyAWTMenu objAppFrame = new MyAWTMenu();
objAppFrame.addWindowListener( //Register an anonymous class as a listener.
new WindowAdapter() {
public void windowClosing( WindowEvent e )
{
System.exit( 0 );
}
}
);
objAppFrame.init();
objAppFrame.setSize( 760, 378);
objAppFrame.setVisible( true );
}

I'd better rewrite it as follows:
public class FooFrame extends JFrame {
public FooFrame() {
// your code, copy/pasted
setBackground(Color.white);
JPanel bottom = new JPanel();
bottom.setBackground(Color.BLACK);
JButton b1 = new JButton("test");
bottom.add(b1);
add(bottom, BorderLayout.CENTER);
// set size & pack
Dimension size = new Dimension(400, 400);
setPreferredSize(size);
setMinimumSize(size);
pack();
setLocationRelativeTo(null);
}
public static void main(String args[]) {
java.awt.EventQueue.invokeLater(new Runnable() {
public void run() {
new FooFrame().setVisible(true);
}
});
}
}

add(bottom,BorderLayout.SOUTH);
in your init()
Here's your code that i was running. It seems to work fine for me. I did add a call to pack();
import java.awt.BorderLayout;
import java.awt.Color;
import java.awt.event.WindowAdapter;
import java.awt.event.WindowEvent;
import javax.swing.JButton;
import javax.swing.JPanel;
public class MyAWTMenu extends java.awt.Frame// implements ActionListener
{
public void init() {
setBackground(Color.white);
JPanel bottom = new JPanel();
bottom.setBackground(Color.BLACK);
JButton b1 = new JButton("test");
bottom.add(b1);
bottom.setVisible(true);
add(bottom, BorderLayout.SOUTH);
pack();
}
public static void main(String args[]) {
MyAWTMenu objAppFrame = new MyAWTMenu();
objAppFrame.addWindowListener( //Register an anonymous class as a listener.
new WindowAdapter() {
public void windowClosing(WindowEvent e) {
System.exit(0);
}
});
objAppFrame.init();
objAppFrame.setSize(760, 378);
objAppFrame.setVisible(true);
}
}