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How can I change the JPanel from another Class?

Hi, I'm new to Java and I have the following problem:
I created a JFrame and I want the JPanel to change when clicking a JButton. That does almost work.The only problem is that the program creates a new window and then there are two windows. One with the first JPanel and one with the second JPanel.
Here is my current code:
first class:
public class Program {
public static void main (String [] args) {
new window(new panel1());
}
}
second class:
import java.awt.Toolkit;
import javax.swing.JFrame;
import javax.swing.JPanel;
public class Window extends JFrame {
private static final long serialVersionUID = 1L;
Window(JPanel panel) {
setLocation((int) Toolkit.getDefaultToolkit().getScreenSize().getWidth() / 2 - 200,
(int) Toolkit.getDefaultToolkit().getScreenSize().getHeight() / 2 - 100);
setSize(400, 200);
setTitle("test");
setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
setResizable(false);
setContentPane(panel);
setVisible(true);
}
}
third class:
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import javax.swing.JButton;
import javax.swing.JPanel;
public class Panel1 extends JPanel {
private final long serialVersionUID = 1L;
Panel1() {
JButton nextPanelButton = new JButton("click here");
add(nextPanelButton);
ActionListener changePanel = new ActionListener() {
#Override
public void actionPerformed(ActionEvent event) {
new window(new panel2());
}
};
nextPanelButton.addActionListener(changePanel);
}
}
fourth class:
public class Panel2 extends JPanel {
private static final long serialVersionUID = 1L;
Panel2() {
JLabel text = new JLabel("You pressed the Button!");
add(text);
}
}
But I just want to change the JPanel without opening a new window. Is there a way to do that?
Thanks in advance!

This is a demo
import javax.swing.*;
public class Main {
public static void main(String[] args) {
SwingUtilities.invokeLater(() -> {
new MainFrame("Title").setVisible(true);
});
}
}
MainFrame.java
import javax.swing.*;
import java.awt.*;
public class MainFrame extends JFrame {
private JPanel viewPanel;
public MainFrame(String title) {
super(title);
createGUI();
}
private void createGUI() {
setDefaultCloseOperation(JFrame.DISPOSE_ON_CLOSE);
setLayout(new BorderLayout());
setMinimumSize(new Dimension(600, 480));
viewPanel = new JPanel(new BorderLayout());
add(viewPanel, BorderLayout.CENTER);
showView(new View1(this));
pack();
}
public void showView(JPanel panel) {
viewPanel.removeAll();
viewPanel.add(panel, BorderLayout.CENTER);
viewPanel.revalidate();
viewPanel.repaint();
}
}
View1.java
import javax.swing.*;
import java.awt.*;
public class View1 extends JPanel {
final private MainFrame owner;
public View1(MainFrame owner) {
super();
this.owner = owner;
createGUI();
}
private void createGUI() {
setLayout(new FlowLayout());
add(new JLabel("View 1"));
JButton button = new JButton("Show View 2");
button.addActionListener(event -> {
SwingUtilities.invokeLater(() -> owner.showView(new View2(owner)));
});
add(button);
}
}
View2.java
import javax.swing.*;
import java.awt.*;
public class View2 extends JPanel {
final private MainFrame owner;
public View2(MainFrame owner) {
super();
this.owner = owner;
createGUI();
}
private void createGUI() {
setLayout(new FlowLayout());
add(new JLabel("View 2"));
JButton button = new JButton("Show View 1");
button.addActionListener(event -> {
SwingUtilities.invokeLater(() -> owner.showView(new View1(owner)));
});
add(button);
}
}

First of all, take a look at Java naming conventions, in particular your class names should start with a capitalized letter.
If you want to avoid to open a new window every time you click the button, you could pass your frame object to Panel1 constructor, and setting a new Panel2 instance as the frame content pane when you click the button. There is also no need to pass Panel1 to Window constructor (please note that Window class is already defined in java.awt package, it would be better to avoid a possible name clash renaming your class ApplicationWindow, MyWindow or something else).
You could change your code like this (only relevant parts):
public class Program
{
public static void main (String [] args) {
SwingUtilities.invokeLater (new Runnable () {
#Override public void run () {
new Window ().setVisible (true);
}
};
}
}
class Window extends JFrame
{
// ...
Window () {
// ...
setContentPane(new Panel1 (this));
}
}
class Panel1 extends JPanel
{
// ...
Panel1 (JFrame parent) {
// ...
ActionListener changePanel = new ActionListener() {
#Override
public void actionPerformed(ActionEvent event) {
parent.setContentPane (new Panel2 ());
}
};
// ...
}
Also note the SwingUtilities's invokeLater call, which is the best way to initialise your GUI in the EDT context (for more info look at this question).
Finally, you could avoid to create a new Panel2 instance every time you click the button, simply by using a CardLayout.
Take a look at the official tutorial.

This is an old post, but it may be useful to answer it in a simplified way. Thanks to mr mcwolf for the first answer.
If we want to make 1 child jframe interact with a main jframe in order to modify its content, let's consider the following case.
parent.java and child.java.
So, in parent.java, we have something like this:
Parent.java
public class Parent extends JFrame implements ActionListener{
//attributes
//here is the class we want to modify
private some_class_to_modify = new some_class_to_modify();
//here is a container which contains the class to modify
private JPanel container = new JPanel();
private some_class = new some_class();
private int select;
//....etc..etc
//constructor
public Parent(){
this.setTitle("My title");
//etc etc
//etc....etc
container.add(some_class_to_modify,borderLayout.CENTER);
}
//I use for instance actionlisteners on buttons to trigger the new JFrame
public void actionPerformed(ActionEvent arg0){
if((arg0.getSource() == source_button_here)){
//Here we call the child class and send the parent's attributes with "this"
Child child = new Child(this);
}
//... all other cases
}//Here is the class where we want to be able to modify our JFrame. Here ist a JPanel (Setcolor)
public void child_action_on_parent(int selection){
this.select = selection;
System.out.println("Selection is: "+cir_select);
if(select == 0) {
//Do $omething with our class to modify
some_class_to_modify.setcolor(Color.yellow);
}
}
In child.java we would have something like this:
public class Child extends JFrame implements ActionListener {
//Again some attributes here
private blabla;
//Import Parent JFrame class
private Parent owner;
private int select_obj=0;
//Constructor here and via Parent Object Import
public Child(Parent owner){
/*By calling the super() method in the constructor method, we call the parent's
constructor method and gets access to the parent's properties and methods:*/
super();
this.owner = owner;
this.setTitle("Select Method");
this.setSize(400, 400);
this.setContentPane(container);
this.setVisible(true);
}
class OK_Button implements ActionListener {
public void actionPerformed(ActionEvent e) {
Object Selection = select;
if(Selection == something) {
select_obj=0;
valid = JOptionPane.showConfirmDialog(null,"You have chosen option 1. Do you want to continue?","Minimum diameter",2);
}
System.out.println("Option is:"+valid);
if(valid == 0) {
setVisible(false);
//Here we can use our herited object to call the child_action_on_parent public class of the Parent JFrame. So it can modify directly the Panel
owner.child_action_on_parent(select_obj);
}
}
}

Repainting a JPanel

I have two frames with contents . The first one has a jlabel and jbutton which when it is clicked it will open a new frame. I need to repaint the first frame or the panel that has the label by adding another jlabel to it when the second frame is closed.
//Edited
import java.awt.BorderLayout;
import java.awt.Dimension;
import java.awt.GridLayout;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.awt.event.KeyEvent;
import java.awt.event.KeyListener;
import java.awt.event.WindowAdapter;
import java.awt.event.WindowEvent;
import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JPanel;
import javax.swing.JTextField;
public class FirstFrame extends JPanel implements KeyListener{
private static String command[];
private static JButton ok;
private static int count = 1;
private static JTextField text;
private static JLabel labels[];
private static JPanel p ;
private static JFrame frame;
public int getCount(){
return count;
}
public static void createWindow(){
JFrame createFrame = new JFrame();
JPanel panel = new JPanel(new GridLayout(2,1));
text = new JTextField (30);
ok = new JButton ("Add");
ok.requestFocusInWindow();
ok.setFocusable(true);
panel.add(text);
panel.add(ok);
text.setFocusable(true);
text.addKeyListener(new FirstFrame());
createFrame.add(panel);
createFrame.setVisible(true);
createFrame.setSize(600,300);
createFrame.setDefaultCloseOperation(JFrame.DISPOSE_ON_CLOSE);
createFrame.setLocationRelativeTo(null);
createFrame.addWindowListener(new WindowAdapter() {
public void windowClosing(WindowEvent windowEvent) {
System.out.println(command[count]);
if(command[count] != null){
p.add(new JLabel("NEW LABEL"));
p.revalidate();
p.repaint();
count++;
System.out.println(count);
}
}
});
if(count >= command.length)
count = 1;
ok.addActionListener(new ActionListener(){
public void actionPerformed(ActionEvent e){
if(command[count] == null)
command[count] = text.getText();
else
command[count] = command[count]+", "+text.getText();
text.setText("");
}
});
}
public FirstFrame(){
p = new JPanel();
JButton create = new JButton ("CREATE");
command = new String[2];
labels = new JLabel[2];
addKeyListener(this);
create.setPreferredSize(new Dimension(200,100));
//setLayout(new BorderLayout());
p.add(new JLabel("dsafsaf"));
p.add(create);
add(p);
//JPanel mainPanel = new JPanel();
/*mainPanel.setFocusable(false);
mainPanel.add(create);
*/
create.addActionListener(new ActionListener(){
public void actionPerformed(ActionEvent e){
createWindow();
}
});
//add(mainPanel, BorderLayout.SOUTH);
}
public static void main(String[] args) {
frame = new JFrame();
frame.add(new FirstFrame());
frame.setVisible(true);
frame.pack();
frame.setDefaultCloseOperation(JFrame.DISPOSE_ON_CLOSE);
}
#Override
public void keyReleased(KeyEvent e) {
}
#Override
public void keyTyped(KeyEvent e) {
}
#Override
public void keyPressed(KeyEvent e) {
if(e.getKeyCode() == KeyEvent.VK_ENTER)
if(ok.isDisplayable()){
ok.doClick();
return;}
}
}
}
});
}
}

As per my first comment, you're better off using a dialog of some type, and likely something as simple as a JOptionPane. For instance in the code below, I create a new JLabel with the text in a JTextField that's held by a JOptionPane, and then add it to the original GUI:
import java.awt.Dimension;
import java.awt.event.ActionEvent;
import javax.swing.*;
#SuppressWarnings("serial")
public class FirstPanel2 extends JPanel {
private static final int PREF_W = 600;
private static final int PREF_H = 300;
private JTextField textField = new JTextField("Hovercraft rules!", 30);
private int count = 0;
public FirstPanel2() {
AddAction addAction = new AddAction();
textField.setAction(addAction);
add(textField);
add(new JButton(addAction));
}
#Override
public Dimension getPreferredSize() {
if (isPreferredSizeSet()) {
return super.getPreferredSize();
}
return new Dimension(PREF_W, PREF_H);
}
private class AddAction extends AbstractAction {
public AddAction() {
super("Add");
}
#Override
public void actionPerformed(ActionEvent e) {
String text = textField.getText();
final JTextField someField = new JTextField(text, 10);
JPanel panel = new JPanel();
panel.add(someField);
int result = JOptionPane.showConfirmDialog(FirstPanel2.this, panel, "Add Label",
JOptionPane.OK_CANCEL_OPTION, JOptionPane.PLAIN_MESSAGE);
if (result == JOptionPane.OK_OPTION) {
JLabel label = new JLabel(someField.getText());
FirstPanel2.this.add(label);
FirstPanel2.this.revalidate();
FirstPanel2.this.repaint();
}
}
}
private static void createAndShowGui() {
FirstPanel2 mainPanel = new FirstPanel2();
JFrame frame = new JFrame("My Gui");
frame.setDefaultCloseOperation(JFrame.DISPOSE_ON_CLOSE);
frame.getContentPane().add(mainPanel);
frame.pack();
frame.setLocationByPlatform(true);
frame.setVisible(true);
}
public static void main(String[] args) {
SwingUtilities.invokeLater(new Runnable() {
public void run() {
createAndShowGui();
}
});
}
}
Also, don't add KeyListeners to text components as that is a dangerous and unnecessary thing to do. Here you're much better off adding an ActionListener, or as in my code above, an Action, so that it will perform an action when the enter key is pressed.
Edit
You ask:
Just realized it is because of the KeyListener. Can you explain please the addAction ?
This is functionally similar to adding an ActionListener to a JTextField, so that when you press enter the actionPerformed(...) method will be called, exactly the same as if you pressed a JButton and activated its ActionListener or Action. An Action is like an "ActionListener" on steroids. It not only behaves as an ActionListener, but it can also give the button its text, its icon and other properties.

How to make a class run after two buttons are pressed

I am making my first game, and the last time I asked this question, I kinda didn't explain it very well. Basically, below is the opening screen of the game. I know, not very good, but it is just a rough draft. Then I also built the game.
There are two buttons in the opening screen, for it is a 2 player game. Both players must click ready, and then I want to program to end, and to start the second program. However I'm not sure how to do that.
import java.awt.*;
import javax.swing.*;
import java.awt.event.*;
public class OpeningScreen {
JFrame frame;
JPanel main;
JButton ready1;
JButton ready2;
JPanel bottom;
JLabel label;
public OpeningScreen(){
UIManager.put("Button.background", Color.cyan);
UIManager.put("Button.foreground", Color.magenta);
UIManager.put("ToolTip.background", Color.magenta);
frame=new JFrame("Super Tuesday");
main=new JPanel();
ready1=new JButton("CLICK IF READY");
ready2=new JButton("CLICK IF READY");
label=new JLabel("SUPER TUESDAY");
bottom=new JPanel();
label.setFont(label.getFont().deriveFont(50.0f));
frame.setSize(480, 800);
frame.setLayout(new BorderLayout());
frame.add(main, BorderLayout.CENTER);
bottom.setLayout(new BorderLayout());
ready1.setToolTipText("CLICK ME TO START THE GAME");
ready2.setToolTipText("CLICK ME TO START THE GAME");
main.setBackground(Color.gray);
label.setForeground(Color.white);
ready1.setFont(ready1.getFont().deriveFont(20.0f));
ready2.setFont(ready2.getFont().deriveFont(20.0f));
ready1.setForeground(Color.pink);
ready2.setForeground(Color.pink);
ready1.setPreferredSize(new Dimension(240,150 ));
ready2.setPreferredSize(new Dimension(240, 150));
bottom.setPreferredSize(new Dimension(600, 150));
main.setLayout(new FlowLayout());
main.add(label, BorderLayout.NORTH);
frame.add(bottom, BorderLayout.SOUTH);
bottom.add(ready1, BorderLayout.WEST);
bottom.add(ready2, BorderLayout.EAST);
MyMouseManager1 mmm1=new MyMouseManager1();
MyMouseManager2 mmm2=new MyMouseManager2();
ready1.addMouseListener(mmm1);
ready2.addMouseListener(mmm2);
frame.setVisible(true);
}
class MyMouseManager1 implements MouseListener{
public void mouseClicked(MouseEvent e) {
ready1.setBackground(Color.green);
ready1.setForeground(Color.white);
ready1.setText("READY!");
}
public void mousePressed(MouseEvent e) {
}
public void mouseReleased(MouseEvent e) {
}
public void mouseEntered(MouseEvent e) {
}
public void mouseExited(MouseEvent e) {
}
public void mouseDragged(MouseEvent e) {
}
public void mouseMoved(MouseEvent e) {
}
}
class MyMouseManager2 implements MouseListener{
public void mouseClicked(MouseEvent e) {
ready2.setBackground(Color.green);
ready2.setForeground(Color.white);
ready2.setText("READY!");
}
public void mousePressed(MouseEvent e) {
}
public void mouseReleased(MouseEvent e) {
}
public void mouseEntered(MouseEvent e) {
}
public void mouseExited(MouseEvent e) {
}
public void mouseDragged(MouseEvent e) {
}
public void mouseMoved(MouseEvent e) {
}
}
public static void main(String[] args){
OpeningScreen smartie=new OpeningScreen();
}
}
Here is the second program. Please don't copy. heh.
import javax.swing.*;
import java.awt.*;
import java.awt.event.MouseEvent;
import java.awt.event.MouseListener;
import java.awt.event.MouseMotionListener;
import java.applet.Applet;
public class Clickasfastasyoucan extends java.applet.Applet{
private JFrame w;
private JPanel b;
private Button p;
private JPanel d;
private int times;
private JLabel number;
JPanel n;
JFrame x;
public Clickasfastasyoucan() {
x=new JFrame(" ");
n=new JPanel();
times=0;
number=new JLabel("How fast can you click?");
w = new JFrame("My Smart Button");
w.setSize(1500, 1000);
b = new JPanel();
p = new Button("Swipe as fast as you can");
w.setSize(500, 500);
b.setPreferredSize(new Dimension(1000,1500));
d=new JPanel();
w.add(b);
b.add(p);
b.setLayout(new GridLayout(1, 1));
b.add(number, BorderLayout.CENTER);
d.setSize(500, 500);
MyMouseManager mmm = new MyMouseManager();
p.addMouseListener(mmm);
p.addMouseMotionListener(mmm);
p.setForeground(Color.white);
p.setBackground(Color.black);
p.setFont(p.getFont().deriveFont(20.0f));
p.setFont(p.getFont().deriveFont(20.0f));
b.setSize(600, 600);
w.setVisible(true);
}
class MyMouseManager implements MouseListener, MouseMotionListener {
public void mouseClicked(MouseEvent e) {
}
public void mousePressed(MouseEvent e) {
n.setBackground(Color.blue);
x.add(n);
x.setSize(500, 500);
n.setSize(500, 500);
x.setVisible(true);
}
public void mouseReleased(MouseEvent e) {
}
public void mouseEntered(MouseEvent e) {
n.setBackground(Color.blue);
}
public void mouseExited(MouseEvent e) {
n.setBackground(Color.white);
}
public void mouseDragged(MouseEvent e) {
}
public void mouseMoved(MouseEvent e) {times++;
number.setFont(number.getFont().deriveFont(100.0f));
number.setText(" "+times+" ");
if (times>=100&&times<999){
b.setBackground(Color.red);
number.setFont(number.getFont().deriveFont(80.0f));
times=times+1;
}
if(times>=1000&&times<10000){
b.setBackground(Color.green);
number.setFont(number.getFont().deriveFont(70.0f));
times=times+4;
}
if(times>=10000&&times<50000){
b.setBackground(Color.yellow);
number.setFont(number.getFont().deriveFont(70.0f));
times=times+100;
}if(times>=50000&&times<500000){
b.setBackground(Color.blue);
number.setFont(number.getFont().deriveFont(70.0f));
times=times+500;
}
if(times>=500000&&times<4999999){
b.setBackground(Color.pink);
number.setFont(number.getFont().deriveFont(40.0f));
times=times+1000;
}
if(times>=5000000){
b.setBackground(Color.orange);
number.setFont(number.getFont().deriveFont(20.0f));
number.setText("WOW! YOU WON. CHECK THE OUTPUT TO SEE HOW YOU SCORED!");
System.out.println("1 day: Are you still there?");
System.out.println("24 hour: Snail speed");
System.out.println("15 hours: Fail");
System.out.println("5 hours: Slow Fingers");
System.out.println("1 hour: Fast Fingers");
System.out.println("30 minutes: Champion");
System.out.println("15 minutes: You beat me!");
System.out.println("2 minutes: Cheater");
System.out.println("1 minute: Speed of Light");
System.out.println("");
System.out.println("");
System.out.println("");
System.out.println("");
System.out.println("");
System.out.println("___________________________-");
}
}
}
public static void main(String[] args) {
Clickasfastasyoucan clickgame= new Clickasfastasyoucan();
}
}
I want this one to replace the first program. I'm not sure how to even start with this though, since this is my first attempt at any game, or anything beyond a one class program.

No, you really don't want a java.awt.Applet to replace a JFrame, trust me. They're both used in two vastly different situations, and while the Swing library that underlies JFrames is about 4 years out of date, the AWT library that underlies java.awt.Applet is about 20 years out of date. Just stay clear of Applet.
Instead your GUI classes should be geared towards creating JPanels, which can then be placed into JFrames or JDialogs, or JTabbedPanes, or swapped via CardLayouts, wherever needed. This will greatly increase the flexibility of your GUI coding, and in fact this is what I recommend -- that you swap views via a CardLayout.
Also -- don't use MouseListeners for your JButton listeners but instead use ActionListeners. MouseListeners won't respond to space bar presses, won't be disabled if the button becomes disabled, and can be capricious if you base behavior on the mouseClicked method. Use the proper tool for the job: ActionListeners, or even better, Actions.
For example:
import java.awt.BorderLayout;
import java.awt.CardLayout;
import java.awt.Dimension;
import java.awt.Font;
import java.awt.GridBagLayout;
import java.awt.GridLayout;
import java.awt.event.ActionEvent;
import java.awt.geom.AffineTransform;
import javax.swing.*;
public class MainGui extends JPanel {
private CardLayout cardLayout = new CardLayout();
private StartUpPanel startUpPanel = new StartUpPanel(this);
private GamePanel gamePanel = new GamePanel(this);
public MainGui() {
setLayout(cardLayout);
add(startUpPanel, startUpPanel.getName());
add(gamePanel, gamePanel.getName());
}
public void nextCard() {
cardLayout.next(this);
}
private static void createAndShowGui() {
MainGui mainPanel = new MainGui();
JFrame frame = new JFrame("MainGui");
frame.setDefaultCloseOperation(JFrame.DISPOSE_ON_CLOSE);
frame.getContentPane().add(mainPanel);
frame.pack();
frame.setLocationByPlatform(true);
frame.setVisible(true);
}
public static void main(String[] args) {
SwingUtilities.invokeLater(new Runnable() {
public void run() {
createAndShowGui();
}
});
}
}
class StartUpPanel extends JPanel {
public static final String CLICK_IF_READY = "Click If Ready";
public static String SUPER_TUESDAY = "SUPER TUESDAY";
public static final String READY = "READY";
public static final int MAX_READY = 2;
private static final float TITLE_FONT_POINTS = 40f;
public static final String START_UP_PANEL = "Startup Panel";
private static final int PREF_W = 600;
private static final int PREF_H = PREF_W;
private int readyCount = 0;
private MainGui mainGui;
public StartUpPanel(MainGui mainGui) {
this.mainGui = mainGui;
setName(START_UP_PANEL);
JLabel titleLabel = new JLabel(SUPER_TUESDAY, SwingConstants.CENTER);
titleLabel.setFont(titleLabel.getFont().deriveFont(Font.BOLD, TITLE_FONT_POINTS));
JButton button1 = new JButton(new StartupAction());
JButton button2 = new JButton(new StartupAction());
button1.setFont(button1.getFont().deriveFont(Font.BOLD, TITLE_FONT_POINTS));
button2.setFont(button1.getFont());
JPanel southPanel = new JPanel(new GridLayout(1, 0));
southPanel.add(button1);
southPanel.add(button2);
setLayout(new BorderLayout());
add(titleLabel, BorderLayout.CENTER);
add(southPanel, BorderLayout.PAGE_END);
}
#Override
public Dimension getPreferredSize() {
Dimension superSize = super.getPreferredSize();
if (isPreferredSizeSet()) {
return superSize;
}
int prefW = Math.max(superSize.width, PREF_W);
int prefH = Math.max(superSize.height, PREF_H);
return new Dimension(prefW, prefH);
}
private class StartupAction extends AbstractAction {
public StartupAction() {
super(CLICK_IF_READY);
}
#Override
public void actionPerformed(ActionEvent e) {
if (getValue(NAME).equals(CLICK_IF_READY)) { // check if button active
putValue(NAME, READY); // swap button's name
((AbstractButton) e.getSource()).setFocusable(false); // lose focus
readyCount++; // increment ready count.
if (readyCount >= MAX_READY) { // if all buttons pushed
mainGui.nextCard(); // tell main GUI to swap cards
}
}
}
}
}
// simple mock class to represent the game
class GamePanel extends JPanel {
public static final String GAME = "Game";
private static final float FONT_POINTS = 30F;
private MainGui mainGui;
public GamePanel(MainGui mainGui) {
this.mainGui = mainGui;
setName(GAME);
JLabel label = new JLabel(GAME, SwingConstants.CENTER);
label.setFont(label.getFont().deriveFont(Font.BOLD, FONT_POINTS));
setLayout(new GridBagLayout());
add(label);
}
}

Java JDialogs How To Pass Information Between?

after looking for an answer for 3 hours, I am just about to give up on this idea:
I am making an application that displays the followers of a Twitch streamer.
A couple of features i am trying to add:
the display frame is a separate window from the controls frame.
I am trying to use (JFrame as display window) (JDialog as controls frame)
And furthermore: Settings is in another JDialog (this one has Modal(true))
Settings needs to be able to send the JFrame information such as: "username" and "text color"
And the settings JDialog will only pop up from clicking "settings" on the controls JDialog.
It will setVisible(false) when you click "save settings" or the X.
On the controls JDialog (b_console) needs to receive error messages and info like that.
And on the same JDialog, "filler" needs to receive follower count and things like that.
Here follows my code involving the transfers listed above:
package javafollowernotifier;
import java.awt.*;
import java.awt.event.*;
import java.awt.Graphics.*;
import javax.swing.*;
import java.io.*;
import java.net.URL;
public class JavaFollowerNotifier extends JFrame implements ComponentListener
{
Settings settings = new Settings();
ControlPanel ctrlPnl = new ControlPanel();
public JavaFollowerNotifier()
{
try
{
settings.readSettings();
}
catch(Exception e)
{
ctrlPnl.b_console.setText("Error");
System.out.println(e);
}
}
public void grabFollower()
{
ctrlPnl.b_console.setText("Retrieving Info...");
try
{
URL twitch = new URL("https://api.twitch.tv/kraken/channels/" + savedSettings[1] + "/follows?limit=1&offset=0");
ctrlPnl.b_console.setText("Retrieved");
}
catch(Exception e)
{
ctrlPnl.b_console.setText("Error");
System.out.println(e);
}
}
public void grabStats()
{
ctrlPnl.b_console.setText("Retrieving Info...");
try
{
URL twitch = new URL("https://api.twitch.tv/kraken/channels/" + savedSettings[1] + "/follows?limit=1&offset=0");
ctrlPnl.filler.setText("Followers: " + totalFollowers + "\nLatest: " + lastFollower);
ctrlPnl.b_console.setText("Retrieved");
}
catch(Exception e)
{
ctrlPnl.b_console.setText("Error");
System.out.println(e);
}
}
public void componentMoved(ComponentEvent arg0)
{
//this is only to *attach this JDialog to the JFrame and make it move together my plan is to have it undecorated as well
int x = this.getX() + this.getWidth();
int y = this.getY();
ctrlPnl.movePanel(x, y);
}
public void paint(Graphics g)
{
if(clearPaint == false)
{
//any "savedSettings[n]" are saved in Settings.java (just not in this version)
g.setColor(Color.decode(savedSettings[3]));
scaledFont = scaleFont(follower + " followed!", bounds, g, new Font(savedSettings[2], Font.PLAIN, 200));
}
}
}
package javafollowernotifier;
import java.awt.*;
import java.awt.event.*;
import java.io.*;
import javax.imageio.ImageIO;
import javax.swing.*;
public class Settings extends JDialog implements ActionListener
{
JavaFollowerNotifier jfollow = new JavaFollowerNotifier();
ControlPanel ctrlPnl = new ControlPanel();
//here are the settings mention above
String[] savedSettings = {"imgs/b_b.jpg","username","font","color","Nightbot"};
public Settings()
{
try
{
UIManager.setLookAndFeel(UIManager.getSystemLookAndFeelClassName());
}
catch (Exception e)
{
ctrlPnl.b_console.setText("Error");
System.out.println(e);
}
}
public void saveSettings()
{
savedSettings[4] = jfollow.lastFollower;
try
{
PrintWriter save = new PrintWriter("config.cfg");
ctrlPnl.b_console.setText("Saving...");
for(int i = 0; i < 5; i++)
{
save.println(savedSettings[i]);
}
save.close();
ctrlPnl.b_console.setText("Saved");
}
catch(Exception e)
{
ctrlPnl.b_console.setText("Error");
System.out.println(e);
canClose = false;
}
readSettings();
this.repaint();
}
public void readSettings()
{
ctrlPnl.b_console.setText("Loading...");
try
{
}
catch(Exception e)
{
ctrlPnl.b_console.setText("Error");
System.out.println(e);
}
jfollow.lastFollower = savedSettings[4];
try
{
}
catch(Exception e)
{
ctrlPnl.b_console.setText("Error");
System.out.println(e);
}
ctrlPnl.b_console.setText("Loaded Settings");
}
}
package javafollowernotifier;
import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
public class ControlPanel extends JDialog implements ActionListener
{
public ControlPanel()
{
try
{
}
catch (Exception e)
{
b_console.setText("Error");
System.out.println(e);
}
}
public void movePanel(int x, int y)
{
//here is where i *attach the JDialog to the JFrame
controlPanel.setLocation(x, y);
}
public void actionPerformed(ActionEvent ie)
{
if(ie.getSource() == b_settings)
{
settings.frame.setVisible(true);
}
}
}

I tried to fix your program, but I wasn't too sure about its flow. So I created another simple one. What I did was pass the labels from the main frame to the dialogs' constructors. In the dialog, I took those labels and changed them with text entered in their text fields. If you hit enter after writing text from the dialog, you'll see the text in the frame change
public class JavaFollowerNotifier1 extends JFrame{
private JLabel controlDialogLabel = new JLabel(" ");
private JLabel settingDialogLabel = new JLabel(" ");
private ControlDialog control;
private SettingsDialog settings;
public JavaFollowerNotifier1() {
control = new ControlDialog(this, true, controlDialogLabel);
settings = new SettingsDialog(this, true, settingDialogLabel);
....
class ControlDialog extends JDialog {
private JLabel label;
public ControlDialog(final Frame frame, boolean modal, final JLabel label) {
super(frame, modal);
this.label = label;
....
class SettingsDialog extends JDialog {
private JLabel label;
public SettingsDialog(final Frame frame, boolean modal, final JLabel label) {
super(frame, modal);
this.label = label;
Test it out and let me know if you have any questions
import java.awt.BorderLayout;
import java.awt.Frame;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import javax.swing.JButton;
import javax.swing.JDialog;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JPanel;
import javax.swing.JTextField;
import javax.swing.SwingUtilities;
public class JavaFollowerNotifier1 extends JFrame{
private JLabel controlDialogLabel = new JLabel(" ");
private JLabel settingDialogLabel = new JLabel(" ");
private JButton showControl = new JButton("Show Control");
private JButton showSetting = new JButton("Show Settings");
private ControlDialog control;
private SettingsDialog settings;
public JavaFollowerNotifier1() {
control = new ControlDialog(this, true, controlDialogLabel);
settings = new SettingsDialog(this, true, settingDialogLabel);
showControl.addActionListener(new ActionListener(){
public void actionPerformed(ActionEvent e) {
control.setVisible(true);
}
});
showSetting.addActionListener(new ActionListener(){
public void actionPerformed(ActionEvent e) {
settings.setVisible(true);
}
});
JPanel buttonPanel = new JPanel();
buttonPanel.add(showControl);
buttonPanel.add(showSetting);
add(buttonPanel, BorderLayout.SOUTH);
add(controlDialogLabel, BorderLayout.NORTH);
add(settingDialogLabel, BorderLayout.CENTER);
pack();
setDefaultCloseOperation(EXIT_ON_CLOSE);
setLocationRelativeTo(null);
setVisible(true);
}
public static void main(String[] args) {
SwingUtilities.invokeLater(new Runnable() {
public void run() {
new JavaFollowerNotifier1();
}
});
}
}
class ControlDialog extends JDialog {
private JLabel label;
private JTextField field = new JTextField(15);
private JButton button = new JButton("Close");
private String s = "";
public ControlDialog(final Frame frame, boolean modal, final JLabel label) {
super(frame, modal);
this.label = label;
setLayout(new BorderLayout());
add(field, BorderLayout.NORTH);
add(button, BorderLayout.CENTER);
pack();
setLocationRelativeTo(frame);
field.addActionListener(new ActionListener(){
public void actionPerformed(ActionEvent e) {
s = field.getText();
label.setText("Message from Control Dialog: " + s);
}
});
button.addActionListener(new ActionListener(){
public void actionPerformed(ActionEvent e) {
ControlDialog.this.setVisible(false);
}
});
}
}
class SettingsDialog extends JDialog {
private JLabel label;
private JTextField field = new JTextField(15);
private JButton button = new JButton("Close");
private String s = "";
public SettingsDialog(final Frame frame, boolean modal, final JLabel label) {
super(frame, modal);
this.label = label;
setLayout(new BorderLayout());
add(field, BorderLayout.NORTH);
add(button, BorderLayout.CENTER);
pack();
setLocationRelativeTo(frame);
field.addActionListener(new ActionListener(){
public void actionPerformed(ActionEvent e) {
s = field.getText();
label.setText("Message from Settings Dialog: " + s);
}
});
button.addActionListener(new ActionListener(){
public void actionPerformed(ActionEvent e) {
SettingsDialog.this.setVisible(false);
}
});
}
}

Typically when I build GUI's which use modal dialogs to gather user input, I build my own class, which extends the JDialog or in some cases a JFrame. In that class I expose a getter method for an object which I usually call DialgResult. This object acts as the Model for the input I gather from the user. In the class that has the button, or whatever control which triggers asking the user for the information, I create it, show it as a modal dialog, then when it is closed, I retrieve the object using that same getter.
This is a very primitive example:
package arg;
import java.awt.Component;
import java.awt.Dimension;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.awt.event.MouseEvent;
import java.awt.event.MouseListener;
import javax.swing.BoxLayout;
import javax.swing.JButton;
import javax.swing.JDialog;
import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.JTextField;
public class asdfas extends JFrame {
public static void main(String[] args) {
asdfas ex = new asdfas();
ex.setVisible(true);
}
public asdfas() {
init();
}
private void init() {
this.setDefaultCloseOperation(EXIT_ON_CLOSE);
this.setBounds(100,100,200,200);
final JButton button = new JButton("Show modal dialog");
button.addActionListener( new ActionListener() {
#Override
public void actionPerformed(ActionEvent arg0) {
Dialog d = new Dialog();
d.setVisible(true);
button.setText(d.getDialogResult().value);
revalidate();
repaint();
}
});
this.add(button);
}
class DialogResult {
public String value;
}
class Dialog extends JDialog {
JTextField tf = new JTextField(20);
private DialogResult result = new DialogResult();
public Dialog() {
super();
init();
}
private void init() {
this.setModal(true);
this.setSize(new Dimension(100,100));
JButton ok = new JButton("ok");
ok.addActionListener( new ActionListener () {
#Override
public void actionPerformed(ActionEvent arg0) {
result = new DialogResult();
result.value = tf.getText();
setVisible(false);
}
});
JPanel p = new JPanel();
p.setLayout(new BoxLayout(p, BoxLayout.Y_AXIS));
p.add(tf);
p.add(ok);
this.add(p);
}
public DialogResult getDialogResult() {
return result;
}
}
}

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.