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Is there a way to reference setVisible() and dispose() from an ActionListener in a separate class file?

I'm working on a very complicated, multi-layered Swing GUI, and the main issue I'm running into right now involves having a JButton ActionListener perform setVisible() on a separate JFrame and immediately dispose() of the current JFrame. Because of the length of my code, it's important that main, both JFrames, and the ActionListener are all split into individual class files. I wrote a VERY simplified version of my problem, split into 4 tiny class files. Here they are:
File 1:
import javax.swing.*;
public class Test {
public static void main(String[] args) {
JFrame g1 = new GUI1();
g1.pack();
g1.setLocation(200,200);
g1.setVisible(true);
JFrame g2 = new GUI2();
g2.pack();
g2.setLocation(400,200);
g2.setVisible(false);
}
}
File 2:
import javax.swing.*;
public class GUI1 extends JFrame {
JPanel panel;
JButton button;
public GUI1() {
super("GUI1");
setDefaultCloseOperation(EXIT_ON_CLOSE);
panel = new JPanel();
button = new JButton("Create GUI2");
button.addActionListener(new Listener());
add(panel);
add(button);
}
}
File 3:
import javax.swing.*;
public class GUI2 extends JFrame {
JPanel panel;
JLabel label;
public GUI2() {
super("GUI2");
setDefaultCloseOperation(EXIT_ON_CLOSE);
panel = new JPanel();
label = new JLabel("I'm alive!");
add(panel);
add(label);
}
}
File 4:
import java.awt.event.*;
public class Listener implements ActionListener {
public void actionPerformed(ActionEvent e) {
GUI2.setVisible(true);
GUI1.dispose();
}
}
As you can see, the only function of the ActionListener is to set GUI2 to visible and dispose of GUI1, but it runs the error "non-static method (setVisible(boolean) and dispose()) cannot be referenced from a static context". I figure this is because both methods are trying to reference objects that were created in main, which is static. My confusion is how to get around this, WITHOUT combining everything into one class.
Any suggestions? Thanks!
EDIT:
Here's the above code compiled into one file... although it returns the exact same error.
import javax.swing.*;
import java.awt.event.*;
public class Test {
public static void main(String[] args) {
JFrame g1 = new GUI1();
g1.pack();
g1.setLocation(200,200);
g1.setVisible(true);
JFrame g2 = new GUI2();
g2.pack();
g2.setLocation(400,200);
g2.setVisible(false);
}
}
class GUI1 extends JFrame {
JPanel panel;
JButton button;
public GUI1() {
super("GUI1");
setDefaultCloseOperation(EXIT_ON_CLOSE);
panel = new JPanel();
button = new JButton("Create GUI2");
button.addActionListener(new Listener());
add(panel);
add(button);
}
}
class GUI2 extends JFrame {
JPanel panel;
JLabel label;
public GUI2() {
super("GUI2");
setDefaultCloseOperation(EXIT_ON_CLOSE);
panel = new JPanel();
label = new JLabel("I'm alive!");
add(panel);
add(label);
}
}
class Listener implements ActionListener {
public void actionPerformed(ActionEvent e) {
GUI2.setVisible(true);
GUI1.dispose();
}
}

You have to pass instances of frame1 and frame2 to your ActionListener.
import java.awt.event.*;
public class Listener implements ActionListener {
private JFrame frame1, frame2;
public Listener(JFrame frame1, JFrame frame2) {
this.frame1 = frame1;
this.frame2 = frame2;
}
public void actionPerformed(ActionEvent e) {
frame2.setVisible(true);
frame1.dispose();
}
}
This means you have to pass an instance of frame2 to your GUI1 class.
import javax.swing.*;
public class GUI1 extends JFrame {
JPanel panel;
JButton button;
public GUI1(JFrame frame2) {
super("GUI1");
setDefaultCloseOperation(EXIT_ON_CLOSE);
panel = new JPanel();
button = new JButton("Create GUI2");
button.addActionListener(new Listener(this, frame2));
add(panel);
add(button);
}
}
This means you have to create the frames in the reverse order.
import javax.swing.*;
public class Test {
public static void main(String[] args) {
JFrame g2 = new GUI2();
g2.pack();
g2.setLocation(400,200);
g2.setVisible(false);
JFrame g1 = new GUI1(g2);
g1.pack();
g1.setLocation(200,200);
g1.setVisible(true);
}
}

Can I communicate between two JFrames WITHOUT using static variables or methods?

Basically, I'm trying to get the JButton in Frame1 to edit the JLabel in Frame2. I know it can work if I set the JLabel and getLabel() method in Frame2 to static, and have the ActionListener reference Frame1 directly, but I want to know if there's a way to do it without using static variables or methods.
Here's the code:
import javax.swing.*;
import java.awt.*;
import java.awt.event.*;
public class Test {
public static void main(String[] args) {
Frame2 f2 = new Frame2();
f2.pack();
f2.setLocation(700, 400);
f2.setVisible(true);
Frame1 f1 = new Frame1(f2);
f1.pack();
f1.setLocation(400, 400);
f1.setVisible(true);
}
}
class Frame1 extends JFrame {
JButton button;
public Frame1(JFrame f) {
super("Frame 1");
setDefaultCloseOperation(EXIT_ON_CLOSE);
button = new JButton("Button");
add(button);
button.addActionListener(new Listener(f.getLabel()));
}
}
class Frame2 extends JFrame {
JLabel label;
public Frame2() {
super("Frame 2");
setDefaultCloseOperation(EXIT_ON_CLOSE);
label = new JLabel("hello");
add(label);
}
public JLabel getLabel() {
return label;
}
}
class Listener implements ActionListener {
private JLabel lab;
public Listener(JLabel lab) {
this.lab = lab;
}
public void actionPerformed(ActionEvent e) {
lab.setText("nice");
}
}
Any suggestions? Thanks!
EDIT: Here's a compilable version of the code -- label and getLabel() are static, and the ActionListener references JFrame1 directly when it's called. My goal is to have no static variables or methods (outside of main).
import javax.swing.*;
import java.awt.*;
import java.awt.event.*;
public class Test {
public static void main(String[] args) {
Frame2 f2 = new Frame2();
f2.pack();
f2.setLocation(700, 400);
f2.setVisible(true);
Frame1 f1 = new Frame1(f2);
f1.pack();
f1.setLocation(400, 400);
f1.setVisible(true);
}
}
class Frame1 extends JFrame {
JButton button;
public Frame1(JFrame f) {
super("Frame 1");
setDefaultCloseOperation(EXIT_ON_CLOSE);
button = new JButton("Button");
add(button);
button.addActionListener(new Listener(Frame2.getLabel()));
}
}
class Frame2 extends JFrame {
static JLabel label;
public Frame2() {
super("Frame 2");
setDefaultCloseOperation(EXIT_ON_CLOSE);
label = new JLabel("hello");
add(label);
}
public static JLabel getLabel() {
return label;
}
}
class Listener implements ActionListener {
private JLabel lab;
public Listener(JLabel lab) {
this.lab = lab;
}
public void actionPerformed(ActionEvent e) {
lab.setText("nice");
}
}

Oracle has a really nifty Swing tutorial. I think your studying the tutorial would be a really good idea.
I had to make a bunch of changes to your code to get it to execute.
The main change I made was to keep the reference to the JLabel in the Frame2 class. I passed an instance of Frame2 to the Listener class. Just like I did yesterday with your previous question.
Here's the code. Take the time to study what I did before you ask another question tomorrow.
import java.awt.BorderLayout;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JPanel;
import javax.swing.SwingUtilities;
public class DoubleJFrameTest {
public static void main(String[] args) {
SwingUtilities.invokeLater(new Runnable() {
#Override
public void run() {
Frame2 f2 = new Frame2();
f2.pack();
f2.setLocation(700, 400);
f2.setVisible(true);
Frame1 f1 = new Frame1(f2);
f1.pack();
f1.setLocation(400, 400);
f1.setVisible(true);
}
});
}
}
class Frame1 extends JFrame {
private static final long serialVersionUID = 1L;
private JButton button;
public Frame1(Frame2 f) {
super("Frame 1");
setDefaultCloseOperation(EXIT_ON_CLOSE);
JPanel panel = new JPanel(new BorderLayout());
button = new JButton("Button");
button.addActionListener(new Listener(f));
panel.add(button, BorderLayout.CENTER);
add(panel);
}
}
class Frame2 extends JFrame {
private static final long serialVersionUID = 1L;
private JLabel label;
public Frame2() {
super("Frame 2");
setDefaultCloseOperation(EXIT_ON_CLOSE);
JPanel panel = new JPanel(new BorderLayout());
label = new JLabel("hello");
panel.add(label, BorderLayout.CENTER);
add(panel);
}
public void setLabelText(String text) {
label.setText(text);;
}
}
class Listener implements ActionListener {
private Frame2 frame;
public Listener(Frame2 frame) {
this.frame = frame;
}
#Override
public void actionPerformed(ActionEvent e) {
frame.setLabelText("nice");
}
}

How to swap JPanel's from an action in a JPanel

I am new(ish) to Java Swing but I have not been able to find an elegant solution to my issue so I thought I'd raise a question here.
I am trying to make my current JPanel change to another JPanel based on a button click event from within the current JPanel. In essence just hiding one panel and displaying the other. I feel this can be done within my MainFrame class however I'm not sure how to communicate this back to it. Nothing I am trying simply seems to do as desired, I'd appreciate any support. Thanks
App.java
public static void main(final String[] args) {
MainFrame mf = new MainFrame();
}
MainFrame.java
public class MainFrame extends JFrame {
public MainFrame(){
setTitle("Swing Application");
setSize(1200, 800);
setDefaultCloseOperation(DISPOSE_ON_CLOSE);
setVisible(true);
// First Page Frame switch
getContentPane().add(new FirstPage());
}
}
FirstPage.java
public class FirstPage extends JPanel {
public FirstPage() {
setVisible(true);
JButton clickBtn = new JButton("Click");
clickBtn.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent actionEvent) {
// Change to SecondPage JPanel here.
}
});
add(clickBtn);
}
}
SecondPage.java
public class SecondPage extends JPanel {
public SecondPage() {
setVisible(true);
add(new JLabel("Welcome to the Second Page"));
}
}
Any more information needed, please ask thanks :)

I think the best way is to use CardLayout. It is created for such cases. Check my example:
public class MainFrame extends JFrame {
private CardLayout cardLayout;
public MainFrame() {
super("frame");
setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
cardLayout = new CardLayout();
getContentPane().setLayout(cardLayout);
getContentPane().add(new FirstPage(this::showPage), Pages.FIRST_PAGE);
getContentPane().add(new SecondPage(this::showPage), Pages.SECOND_PAGE);
setLocationByPlatform(true);
pack();
}
public void showPage(String pageName) {
cardLayout.show(getContentPane(), pageName);
}
public static interface PageContainer {
void showPage(String pageName);
}
public static interface Pages {
String FIRST_PAGE = "first_page";
String SECOND_PAGE = "second_page";
}
public static class FirstPage extends JPanel {
public FirstPage(PageContainer pageContainer) {
super(new FlowLayout());
JButton button = new JButton("next Page");
button.addActionListener(e -> pageContainer.showPage(Pages.SECOND_PAGE));
add(button);
}
}
public static class SecondPage extends JPanel {
public SecondPage(PageContainer pageContainer) {
super(new FlowLayout());
add(new JLabel("This is second page."));
JButton button = new JButton("Go to first page");
button.addActionListener(e -> pageContainer.showPage(Pages.FIRST_PAGE));
add(button);
}
}
public static void main(String[] args) {
SwingUtilities.invokeLater(() -> new MainFrame().setVisible(true));
}
}

CardLayout is the right tool for the job.
You can simply create the ActionListener used to swap pages in JFrame class, and pass a reference of it to FirstPage:
import java.awt.CardLayout;
import java.awt.event.ActionListener;
import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JPanel;
public class MainFrame extends JFrame {
public MainFrame(){
setTitle("Swing Application");
setSize(1200, 800);
setDefaultCloseOperation(DISPOSE_ON_CLOSE);
setLocationByPlatform(true);
//Create card layout and set it to the content pane
CardLayout cLayout = new CardLayout();
setLayout(cLayout);
//create and add second page to the content pane
JPanel secondPage = new SecondPage();
add("SECOND",secondPage);
//create an action listener to swap pages
ActionListener listener = actionEvent ->{
cLayout.show(getContentPane(), "SECOND");
};
//use the action listener in FirstPage
JPanel firstPage = new FirstPage(listener);
add("FIRST", firstPage);
cLayout.show(getContentPane(), "FIRST");
setVisible(true);
}
public static void main(String[] args) {
new MainFrame();
}
}
class FirstPage extends JPanel {
public FirstPage(ActionListener listener) {
JButton clickBtn = new JButton("Click");
clickBtn.addActionListener(listener);
add(clickBtn);
}
}
class SecondPage extends JPanel {
public SecondPage() {
add(new JLabel("Welcome to the Second Page"));
}
}

Java GUI: button controls not Visible

I am having problem displaying my Main Menu on the screen. I don't see where the problem is. All it is displaying is a blank JFrame window. It is not showing my panel with the buttons.
Main Class:
public class Main {
public static void main(String[] args) {
GUIView gui = new GUIView();
}
}
GUIView Class:
import javax.swing.*;
import java.awt.*;
public class GUIView {
protected JFrame frame;
public GUIView() {
frame = new JFrame("Test");
frame.setVisible(true);
frame.setSize(500,500);
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
}
}
MainMenu Class:
import javax.swing.*;
import java.awt.*;
public class MainMenu extends GUIView {
private JButton b1, b2, b3;
private JPanel panel;
public MainMenu() {
GridBagLayout gridbag = new GridBagLayout();
b1 = new JButton();
b2 = new JButton();
b3 = new JButton();
//Button Settings;
b1.setText("Administrator");
b2.setText("Program Leader");
b3.setText("Lecturer");
//Panel Settings
panel = new JPanel();
panel.setLayout(gridbag);
panel.add(b1);
panel.add(b2);
panel.add(b3);
panel.setVisible(true);
super.frame.add(panel);
}
}

You never create an instance of MainMenu. To fix, you could do:
public static void main(String[] args) {
GUIView gui = new MainMenu();
}

Try it this way............
public class Test1 extends JFrame {
int count;
public Test1(){
this.setSize(400,400);
MyCompo m = new MyCompo();
this.add(BorderLayout.CENTER,m);
this.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
}
class MyCompo extends JPanel{
public MyCompo() {
this.setSize(300,300);
setComponents();
//setHandlers();
}
public void paintComponent(Graphics g) {
//setComponents();
}
public void setComponents() {
this.setLayout(new GridLayout(5,4));
this.add(new Button("1"));
this.add(new Button("2"));
this.add(new Button("3"));
this.add(new Button("4"));
this.add(new Button("5"));
this.add(new Button("6"));
this.add(new Button("7"));
this.add(new Button("8"));
}
}
public static void main(String[] args){
EventQueue.invokeLater(new Runnable() {
public void run() {
Test1 t = new Test1();
t.setVisible(true);
}
});
}
}

GUI multiple frames switch

I am writing a program for a black jack game. It is an assignment we are not to use gui's but I am doing it for extra credit I have created two frames ant they are working. On the second frame I want to be able to switch back to the first when a button is pressed. How do I do this?
first window.............
import javax.swing.* ;
import java.awt.event.* ;
import java.awt.* ;
import java.util.* ;
public class BlackJackWindow1 extends JFrame implements ActionListener
{
private JButton play = new JButton("Play");
private JButton exit = new JButton("Exit");
private JPanel pane=new JPanel();
private JLabel lbl ;
public BlackJackWindow1()
{
super();
JPanel pane=new JPanel();
setTitle ("Black Jack!!!!!") ;
JFrame frame = new JFrame("");
setVisible(true);
setSize (380, 260) ;
setLocation (450, 200) ;
frame.setDefaultCloseOperation (JFrame.EXIT_ON_CLOSE) ;
setLayout(new FlowLayout());
play = new JButton("Start");
exit = new JButton("exit");
lbl = new JLabel ("Welcome to Theodores Black Jack!!!!!");
add (lbl) ;
add(play, BorderLayout.CENTER);
play.addActionListener (this);
add(exit,BorderLayout.CENTER);
exit.addActionListener (this);
}
#Override
public void actionPerformed(ActionEvent event)
{
// TODO Auto-generated method stub
BlackJackWindow2 bl = new BlackJackWindow2();
if (event.getSource() == play)
{
bl.BlackJackWindow2();
}
else if(event.getSource() == exit){
System.exit(0);
}
}
second window....
import javax.swing.* ;
import java.awt.event.* ;
import java.awt.* ;
import java.util.* ;
public class BlackJackWindow2 extends JFrame implements ActionListener
{
private JButton hit ;
private JButton stay ;
private JButton back;
//private JLabel lbl;
public void BlackJackWindow2()
{
// TODO Auto-generated method stub
JPanel pane=new JPanel();
setTitle ("Black Jack!!!!!") ;
JFrame frame = new JFrame("");
setVisible(true);
setSize (380, 260) ;
setLocation (450, 200) ;
frame.setDefaultCloseOperation (JFrame.EXIT_ON_CLOSE) ;
setLayout(new FlowLayout());
hit = new JButton("Hit");
stay = new JButton("stay");
back = new JButton("return to main menu");
// add (lbl) ;
add(hit, BorderLayout.CENTER);
hit.addActionListener (this) ;
add(stay,BorderLayout.CENTER);
stay.addActionListener (this) ;
add(back,BorderLayout.CENTER);
back.addActionListener (this) ;
}
#Override
public void actionPerformed(ActionEvent event)
{
// TODO Auto-generated method stub
BlackJackWindow1 bl = new BlackJackWindow1();
if (event.getSource() == hit)
{
//code for the game goes here i will complete later
}
else if(event.getSource() == stay){
//code for game goes here i will comeplete later.
}
else
{
//this is where i want the frame to close and go back to the original.
}
}
}

The second frame needs a reference to the first frame so that it can set the focus back to the first frame.
Also your classes extend JFrame but they are also creating other frames in their constructors.

A couple of suggestions:
You're adding components to a JPanel that uses FlowLayout but are using BorderLayout constants when doing this which you shouldn't do as it doesn't make sense:
add(play, BorderLayout.CENTER);
Rather, if using FlowLayout, just add the components without those constants.
Also, rather than swap JFrames, you might want to consider using a CardLayout and swapping veiws in a single JFrame. For instance:
import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
public class FooBarBazDriver {
private static final String INTRO = "intro";
private static final String GAME = "game";
private CardLayout cardlayout = new CardLayout();
private JPanel mainPanel = new JPanel(cardlayout);
private IntroPanel introPanel = new IntroPanel();
private GamePanel gamePanel = new GamePanel();
public FooBarBazDriver() {
mainPanel.add(introPanel.getMainComponent(), INTRO);
mainPanel.add(gamePanel.getMainComponent(), GAME);
introPanel.addBazBtnActionListener(new ActionListener() {
#Override
public void actionPerformed(ActionEvent e) {
cardlayout.show(mainPanel, GAME);
}
});
gamePanel.addBackBtnActionListener(new ActionListener() {
#Override
public void actionPerformed(ActionEvent e) {
cardlayout.show(mainPanel, INTRO);
}
});
}
private JComponent getMainComponent() {
return mainPanel;
}
private static void createAndShowUI() {
JFrame frame = new JFrame("Foo Bar Baz");
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.getContentPane().add(new FooBarBazDriver().getMainComponent());
frame.pack();
frame.setLocationRelativeTo(null);
frame.setVisible(true);
}
public static void main(String[] args) {
java.awt.EventQueue.invokeLater(new Runnable() {
public void run() {
createAndShowUI();
}
});
}
}
class IntroPanel {
private JPanel mainPanel = new JPanel();
private JButton baz = new JButton("Baz");
private JButton exit = new JButton("Exit");
public IntroPanel() {
mainPanel.setLayout(new FlowLayout());
baz = new JButton("Start");
exit = new JButton("exit");
mainPanel.add(new JLabel("Hello World"));
mainPanel.add(baz);
mainPanel.add(exit);
exit.addActionListener(new ActionListener() {
#Override
public void actionPerformed(ActionEvent e) {
Window win = SwingUtilities.getWindowAncestor(mainPanel);
win.dispose();
}
});
}
public void addBazBtnActionListener(ActionListener listener) {
baz.addActionListener(listener);
}
public JComponent getMainComponent() {
return mainPanel;
}
}
class GamePanel {
private static final Dimension MAIN_SIZE = new Dimension(400, 200);
private JPanel mainPanel = new JPanel();
private JButton foo;
private JButton bar;
private JButton back;
public GamePanel() {
foo = new JButton("Foo");
bar = new JButton("Bar");
back = new JButton("return to main menu");
mainPanel.add(foo);
mainPanel.add(bar);
mainPanel.add(back);
mainPanel.setPreferredSize(MAIN_SIZE);
}
public JComponent getMainComponent() {
return mainPanel;
}
public void addBackBtnActionListener(ActionListener listener) {
back.addActionListener(listener);
}
}

Since I had to test it myself if it is in fact so easy to implement, I built this simple example. It demonstrates a solution to your problem. Slightly inspired by #jzd's answer (+1 for that).
import java.awt.Color;
import java.awt.HeadlessException;
import java.awt.event.MouseAdapter;
import java.awt.event.MouseEvent;
import java.awt.event.MouseListener;
import javax.swing.JFrame;
import javax.swing.SwingUtilities;
public class FocusChangeTwoFrames
{
public static void main(String[] args)
{
SwingUtilities.invokeLater(new Runnable()
{
#Override
public void run()
{
createGUI();
}
});
}
private static void createGUI() throws HeadlessException
{
final JFrame f2 = new JFrame();
f2.getContentPane().setBackground(Color.GREEN);
final JFrame f1 = new JFrame();
f1.getContentPane().setBackground(Color.RED);
f1.setSize(400, 300);
f1.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
f1.setVisible(true);
MouseListener ml = new MouseAdapter()
{
#Override
public void mousePressed(MouseEvent e)
{
if(f1.hasFocus())
f2.requestFocus();
else
f1.requestFocus();
}
};
f1.addMouseListener(ml);
f2.setSize(400, 300);
f2.setLocation(200, 150);
f2.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
f2.setVisible(true);
f2.addMouseListener(ml);
}
}
Enjoy, Boro.