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How to start 2nd Jframe by click menu item in 1st java windows application (Jframe)

I am using eclipse 4.2 with Java.
I have 2 java program : AppWin.java Form1.java
AppWin.java is gui windows application with menu/menu item1.
Form1.java is a Gui Jframe
I like to call Form1.java from AppWin.java by click the menu/menu item1.
When close Form1.java, it is back to AppWin.java.
This is something like MDIFORM. I really cannot find answer.
Please help , if you know eclipse menu.
Thanks
package top;
import java.awt.EventQueue;
public class AppWin {
private JFrame frame;
/**
* Launch the application.
*/
public static void main(String[] args) {
EventQueue.invokeLater(new Runnable() {
public void run() {
try {
AppWin window = new AppWin();
window.frame.setVisible(true);
} catch (Exception e) {
e.printStackTrace();
}
}
});
}
...
With your help, I made a big step.
Thanks to all of you!
Next is my final demo, in windows 7, eclipse 4.2, java Gui
Hope it is helpful to others.
There are 3 parts : AppWin， Form1， Form2. AppWin is top main which call Form1 and Form2 with menu/item.
//1
package top;
import java.awt.EventQueue;
public class AppWin {
private JFrame frame;
private Form1 form1;
private Form2 form2;
/**
* Launch the application.
*/
public static void main(String[] args) {
EventQueue.invokeLater(new Runnable() {
public void run() {
try {
AppWin window = new AppWin();
window.frame.setVisible(true);
} catch (Exception e) {
e.printStackTrace();
}
}
});
}
/**
* Create the application.
*/
public AppWin() {
initialize();
form1 = new Form1();
form2 = new Form2();
}
/**
* Initialize the contents of the frame.
*/
private void initialize() {
frame = new JFrame();
frame.setBounds(100, 100, 450, 300);
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
JMenuBar menuBar = new JMenuBar();
frame.setJMenuBar(menuBar);
JMenu mnNewMenu = new JMenu("Menu1");
menuBar.add(mnNewMenu);
JMenuItem mntmNewMenuItem = new JMenuItem("menu item1");
mntmNewMenuItem.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent arg0) {
form1.setVisible(true);
}
});
mnNewMenu.add(mntmNewMenuItem);
JMenuItem mntmNewMenuItem_1 = new JMenuItem("menu item2");
mntmNewMenuItem_1.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent arg0) {
form2.setVisible(true);
}
});
mnNewMenu.add(mntmNewMenuItem_1);
JMenu mnNewMenu_1 = new JMenu("Menu2");
menuBar.add(mnNewMenu_1);
JMenuItem mntmMenuItem = new JMenuItem("Menu item3");
mnNewMenu_1.add(mntmMenuItem);
}
}
//2
package top;
import java.awt.BorderLayout;
public class Form1 extends JFrame {
private JPanel contentPane;
private JTextField textField;
/**
* Launch the application.
*/
public static void main(String[] args) {
EventQueue.invokeLater(new Runnable() {
public void run() {
try {
Form1 frame = new Form1();
frame.setDefaultCloseOperation(JFrame.DISPOSE_ON_CLOSE);
frame.setVisible(true);
} catch (Exception e) {
e.printStackTrace();
}
}
});
}
/**
* Create the frame.
*/
public Form1() {
// setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
setBounds(100, 100, 450, 300);
contentPane = new JPanel();
contentPane.setBorder(new EmptyBorder(5, 5, 5, 5));
contentPane.setLayout(new BorderLayout(0, 0));
setContentPane(contentPane);
JLabel lblNewLabel = new JLabel("this Form1");
contentPane.add(lblNewLabel, BorderLayout.WEST);
textField = new JTextField();
contentPane.add(textField, BorderLayout.CENTER);
textField.setColumns(10);
JButton btnNewButton = new JButton("New button");
contentPane.add(btnNewButton, BorderLayout.EAST);
}
}
//3
package top;
import java.awt.BorderLayout;
public class Form2 extends JDialog {
private final JPanel contentPanel = new JPanel();
/**
* Launch the application.
*/
public static void main(String[] args) {
try {
Form2 dialog = new Form2();
dialog.setDefaultCloseOperation(JDialog.DISPOSE_ON_CLOSE);
dialog.setVisible(true);
} catch (Exception e) {
e.printStackTrace();
}
}
/**
* Create the dialog.
*/
public Form2() {
setBounds(100, 100, 450, 300);
getContentPane().setLayout(new BorderLayout());
contentPanel.setLayout(new FlowLayout());
contentPanel.setBorder(new EmptyBorder(5, 5, 5, 5));
getContentPane().add(contentPanel, BorderLayout.CENTER);
{
JLabel lblThisForm = new JLabel("This Form2");
contentPanel.add(lblThisForm);
}
{
JPanel buttonPane = new JPanel();
buttonPane.setLayout(new FlowLayout(FlowLayout.RIGHT));
getContentPane().add(buttonPane, BorderLayout.SOUTH);
{
JButton okButton = new JButton("OK");
okButton.setActionCommand("OK");
buttonPane.add(okButton);
getRootPane().setDefaultButton(okButton);
}
{
JButton cancelButton = new JButton("Cancel");
cancelButton.setActionCommand("Cancel");
buttonPane.add(cancelButton);
}
}
}
}
Thanks again

You better use JDesktopPane + JInternalFrame for that purpose instead. Here's a quick sample.
import java.awt.BorderLayout;
import java.awt.Dimension;
import java.awt.event.ActionEvent;
import javax.swing.AbstractAction;
import javax.swing.JDesktopPane;
import javax.swing.JFrame;
import javax.swing.JInternalFrame;
import javax.swing.JMenu;
import javax.swing.JMenuBar;
import javax.swing.JMenuItem;
import javax.swing.JPanel;
public class JInternalFrameSample {
private JPanel pnlMain;
private JDesktopPane desk;
public JInternalFrameSample(){
pnlMain = new JPanel(new BorderLayout()){
#Override public Dimension getPreferredSize(){
return new Dimension(600,600);
}
};
desk = new JDesktopPane();
JMenuBar bar = new JMenuBar();
JMenu menu = new JMenu("Internal Frame");
JMenuItem item = new JMenuItem();
item.setAction(new AbstractAction("Create New") {
#Override
public void actionPerformed(ActionEvent arg0) {
JInternalFrame iFrame = new JInternalFrame("Created from Menu");
iFrame.setResizable(true);
iFrame.setClosable(true);
iFrame.setIconifiable(true);
iFrame.setSize(new Dimension(300, 300));
iFrame.setLocation(0, 0);
//iFrame.getContentPane().setLayout(new BorderLayout());
//iFrame.getContentPane().add( new YourCustomUI().getUI() );
iFrame.setVisible(true);
desk.add(iFrame);
}
});
menu.add(item);
bar.add(menu);
pnlMain.add(bar, BorderLayout.PAGE_START);
pnlMain.add(desk, BorderLayout.CENTER);
}
private JPanel getUI(){
return pnlMain;
}
public static void main(String[] args){
SwingUtilities.invokeLater(new Runnable() {
public void run() {
JFrame frame = new JFrame("Demo");
frame.getContentPane().setLayout(new BorderLayout());
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.getContentPane().add(new JInternalFrameSample().getUI());
frame.pack();
frame.setVisible(true);
}
});
}
}
See also : How to Use Internal Frames

If you do not like the JDesktopPane and JInternalFrame solution, just use your AppWin JFrame as is, and open modal JDialogs for the rest of the forms, instead of JFrames. Modal dialogs can float around the desktop and do not allow you to click your AppWin, until they are closed.
It is usually better to use just one main JFrame for an application, unless you have some wizard application that moves progressively from one JFrame to the other and back. Even with a wizard app, you can stick with one JFrame and update progressively just the ContentPane with JPanels.
Here is the AppWin JFrame:
public class AppWin extends javax.swing.JFrame {
private Form1 form1;
private Form1 form2;
...
private FormN formN;
public AppWin() {
initComponents();
form1 = new Form1(this, true);
form2 = new Form2(this, true);
...
formN = new FormN(this, true);
}
...
private void jMenuItem1ActionPerformed(java.awt.event.ActionEvent evt) {
form1.setVisible(true);
}
And here is your Form1 JDialog:
public class Form1 extends javax.swing.JDialog {
public Form1(java.awt.Frame parent, boolean modal) {
super(parent, modal);
initComponents();
}
...
private void closeButtonActionPerformed(java.awt.event.ActionEvent evt) {
setVisible(false);
}

I only use NetBeans for GUI building because that's more convenient. In the following I can tell you how to achieve what you want to do but I can't tell you how to layout all the components because NetBeans do that for me.
So basically you want to 1. show secondFrame by clicking a menuitem and then close mainFrame, 2. show mainFrame after closing secondFrame, yes? Then, the key is to pass the reference of mainFrame to secondFrame, and write your own method of formClosing event of secondFrame. Something like this:
In the menuItem method in your mainframe:
private void menuItemActionPerformed(java.awt.event.ActionEvent evt) {
//pass 'this' frame's (mainFrame) reference to the secondFrame
SecondFrame newFrame = new SecondFrame(this);
newFrame.setVisible(true); //show the secondFrame
this.setVisible(false); //hide this frame (mainFrame)
}
In your secondFrame:
public class SecondFrame extends javax.swing.JFrame {
private MainFrame mainFrame;
//define your own constructor that can use mainFrame's reference
public SecondFrame(MainFrame mainFrame) {
initComponents();
this.mainFrame = mainFrame;
}
private void initComponents(){
//bind your own event for closing second frame
setDefaultCloseOperation(javax.swing.WindowConstants.DO_NOTHING_ON_CLOSE);
addWindowListener(new java.awt.event.WindowAdapter() {
public void windowClosing(java.awt.event.WindowEvent evt) {
formWindowClosing(evt);
}
});
/***********your stuff***************/
}
//show mainFrame when closing this frame and then dispose this frame
private void formWindowClosing(java.awt.event.WindowEvent evt) {
mainFrame.setVisible(true);
this.dispose();
}
}
The codes above is for disposing the secondFrame when closing it. If you just want to hide the secondFrame when closing for future use, then the codes will be slightly different. Let me know what you up to.

private void jMenuItem1ActionPerformed(java.awt.event.ActionEvent evt) {
form1.setVisible(true);
dispose();
}

Changing/setting the height of a JTextField in a BorderLayout

I'm trying to set the height of a JTextField. At present its the full size of the displayed JFrame. Any ideas how I set the height to 50?
Edit: Here is the amended code along with screenshot thanks!
public class Display extends JFrame {
private DrawCanvas canvas;
private JTextField Altitude;
private JTextField TASpeed;
private JLabel altButton;
private int countA = 0;
private int countS = 0;
private int Bcount1 = 0;
public String Ccount = Integer.toString(Bcount1);
public Display() {
canvas = new DrawCanvas();
canvas.setPreferredSize(new Dimension(CANVAS_WIDTH, CANVAS_HEIGHT));
canvas.setLayout(new BorderLayout());
Container cp = getContentPane();
cp.setLayout(new BorderLayout());
cp.add(canvas, BorderLayout.LINE_START);
//here are the 2 side fields![enter image description here][2]
Altitude = new JTextField("0", 5);
Altitude.setHorizontalAlignment(JTextField.CENTER);
Altitude.setEditable(false);
Altitude.setOpaque(false);
Altitude.setFont(Altitude.getFont().deriveFont(25f));
TASpeed = new JTextField("0", 5);
TASpeed.setHorizontalAlignment(JTextField.CENTER);
TASpeed.setEditable(false);
TASpeed.setOpaque(false);
TASpeed.setFont(Altitude.getFont().deriveFont(25f));
altButton = new JLabel();
altButton.setText(Ccount);
canvas.add(altButton, BorderLayout.SOUTH);
canvas.add(Altitude, BorderLayout.LINE_END);
canvas.add(TASpeed, BorderLayout.LINE_START);
canvas.add(new JLabel(Ccount), BorderLayout.SOUTH);
setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
setTitle("FLIGHT DISPLAY");
pack();
setVisible(true);
requestFocus();
}
class DrawCanvas extends JPanel {
public void paintComponent(Graphics g) {
super.paintComponent(g);
setBackground(CANVAS_BACKGROUND);
g.setColor(GROUND_COLOR);
g.drawString(Ccount, 100, 100);
}
}
public static void main(String[] args) {
SwingUtilities.invokeLater(new Runnable() {
public void run() {
new Display();
}
});
}
}

As #kleopatra correctly comments, the JTextField can calculate it's own preferred size based on the platform designer's choice of Font. This example changes the size.
import java.awt.BorderLayout;
import java.awt.Dimension;
import java.awt.EventQueue;
import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.JTextField;
/** #see http://stackoverflow.com/a/14734937/230513 */
public class Test {
private void display() {
JFrame f = new JFrame("Test");
f.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
JTextField tfCount = new JTextField("42", 8);
tfCount.setHorizontalAlignment(JTextField.CENTER);
tfCount.setFont(tfCount.getFont().deriveFont(50f));
f.add(tfCount, BorderLayout.NORTH);
f.add(new JPanel() { //placeholder
#Override
public Dimension getPreferredSize() {
return new Dimension(320, 240);
}
}, BorderLayout.CENTER);
f.pack();
f.setLocationRelativeTo(null);
f.setVisible(true);
}
public static void main(String[] args) {
EventQueue.invokeLater(new Runnable() {
#Override
public void run() {
new Test().display();
}
});
}
}

Removing JPanel from a JFrame

I am trying to remove a JPanel not hide it but i can't find anything that works.
This is the code in the panel that needs to remove itself when a button is pressed:
play.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent e) {
Frame frame = new Frame(); //referencing to my JFrame class (this class is a JPanel)
//need to remove this panel on this line
frame.ThreeD(); // adds a new panel
}
});
UPDATED
This is the full code:
package ThreeD;
import java.awt.Rectangle;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import javax.swing.JButton;
import javax.swing.JPanel;
import javax.swing.UIManager;
import Run.Frame;
public class Launcher extends JPanel{
private JButton play, options, help, mainMenu;
private Rectangle rplay, roptions, rhelp, rmainMenu;
private int buttonWidthLocation, buttonWidth, buttonHeight;
private int width = 1280;
public Launcher() {
this.setLayout(null);
drawButtons();
}
private void drawButtons() {
try {
UIManager.setLookAndFeel(UIManager.getSystemLookAndFeelClassName());
} catch(Exception e) {
e.printStackTrace();
}
play = new JButton("Play");
options = new JButton("Options");
help = new JButton("Help");
mainMenu = new JButton("Main Menu");
buttonWidthLocation = (width / 2) - (buttonWidth / 2);
buttonWidth = 80;
buttonHeight = 40;
rplay = new Rectangle(buttonWidthLocation, 150, buttonWidth, buttonHeight);
roptions = new Rectangle(buttonWidthLocation, 300, buttonWidth, buttonHeight);
rhelp = new Rectangle(buttonWidthLocation, 450, buttonWidth, buttonHeight);
rmainMenu = new Rectangle(buttonWidthLocation, 600, buttonWidth, buttonHeight);
play.setBounds(rplay);
options.setBounds(roptions);
help.setBounds(rhelp);
mainMenu.setBounds(rmainMenu);
add(play);
add(options);
add(help);
add(mainMenu);
play.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent e) {
Frame frame = new Frame();
//need to remove this panel here
frame.ThreeD();
}
});
options.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent e) {
System.out.println("options");
}
});
help.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent e) {
System.out.println("help");
}
});
mainMenu.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent e) {
System.out.println("mainMenu");
}
});
}
}
And this is my Frame class:
package Run;
import javax.swing.*;
import ThreeD.Display;
import ThreeD.Launcher;
import TowerDefence.Window;
import java.awt.*;
import java.awt.image.BufferedImage;
public class Frame extends JFrame{
public static String title = "Game";
/*public static int GetScreenWorkingWidth() {
return java.awt.GraphicsEnvironment.getLocalGraphicsEnvironment().getMaximumWindowBounds().width;
}*/
/*public static int GetScreenWorkingHeight() {
return java.awt.GraphicsEnvironment.getLocalGraphicsEnvironment().getMaximumWindowBounds().height;
}*/
//public static Dimension size = new Dimension(GetScreenWorkingWidth(), GetScreenWorkingHeight());
public static Dimension size = new Dimension(1280, 774);
public static void main(String args[]) {
Frame frame = new Frame();
System.out.println("Width of the Frame Size is "+size.width+" pixels");
System.out.println("Height of the Frame Size is "+size.height+" pixels");
}
public Frame() {
setTitle(title);
setSize(size);
setResizable(false);
setLocationRelativeTo(null);
setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
ThreeDLauncher();
}
public void ThreeDLauncher() {
Launcher launcher = new Launcher();
add(launcher);
setVisible(true);
}
public void TowerDefence() {
setLayout(new GridLayout(1, 1, 0, 0));
Window window = new Window(this);
add(window);
setVisible(true);
}
public void ThreeD() {
BufferedImage cursor = new BufferedImage(16, 16, BufferedImage.TYPE_INT_ARGB);
Cursor blank = Toolkit.getDefaultToolkit().createCustomCursor(cursor, new Point(0, 0), "blank");
getContentPane().setCursor(blank);
Display display = new Display();
add(display);
setVisible(true);
display.start();
}
}

Basically - you are creating new instance of Frame in line:
Frame frame = new Frame(); //referencing to my JFrame class (this class is a JPanel)
New instance of Frame is not visible, and you're try to remove your Launcher from not visible new Frame. But this is wrong - you should remove Launcher from Frame that you created previously in main function (that is: parent of Launcher component).
Here goes an example:
public class TestFrame extends JFrame {
public static void main(String[] args) {
SwingUtilities.invokeLater(new Runnable() {
#Override
public void run() {
TestFrame frame = new TestFrame();
frame.getContentPane().add(new MyPanel(frame));
frame.setSize(200, 200);
frame.setLocationRelativeTo(null);
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.setVisible(true);
}
});
}
}
And MyPanel class:
public class MyPanel extends JPanel {
public MyPanel(final TestFrame frame) {
JButton b = new JButton("Play");
add(b);
b.addActionListener(new ActionListener() {
#Override
public void actionPerformed(ActionEvent e) {
Container pane = frame.getContentPane();
pane.remove(MyPanel.this);
JPanel otherPanel = new JPanel();
otherPanel.add(new JLabel("OtherPanel"));
pane.add(otherPanel);
pane.revalidate();
}
});
}
}
In your example you should add a reference to Frame in your Launcher constructor:
public Launcher(Frame frame) {
this.frame = frame;
...
Init Launcher:
public void ThreeDLauncher() {
Launcher launcher = new Launcher(this);
and use:
play.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent e) {
//need to remove this panel here
frame.getContentPane().remove(Launcher.this);
frame.ThreeD();
}
});

Say your panel is myPanel you can remove it from the main frame by:
frame.getContentPane().remove(myPanel);

How to override windowsClosing event in JFrame

i'm developing a JFrame which has a button to show another JFrame. On the second JFrame i want to override WindowsClosing event to hide this frame but not close all the application. So i do like this:
On second JFrame
addWindowListener(new java.awt.event.WindowAdapter() {
public void windowClosing(java.awt.event.WindowEvent evt) {
formWindowClosing(evt);
}
});
private void formWindowClosing(java.awt.event.WindowEvent evt) {
this.dispose();
}
but application still close when i click x button on the windows. why? can you help me?
I can't use
setDefaultCloseOperation(DISPOSE_ON_CLOSE);
because i need to show again that JFrame with some information added in it during operations from first JFrame. So i init second JFrame with attribute visible false. if i use dispose i lose the information added in a second moment by the other JFrame. so i use
private void formWindowClosing(java.awt.event.WindowEvent evt) {
this.setVisible(false);
}
but it still continue to terminate my entire app.

don't create a new JFrame, for new container use JDialog, if you want to hide the JFrame then better would be override proper e.g DefaultCloseOperations(JFrame.HIDE_ON_CLOSE), method JFrame.EXIT_ON_CLOSE teminating current JVM instance simlair as calll for System.exit(int)
EDIT
but it still continue to terminate my entire app.
1) then there must be another issue, your code maybe call another JFrame or formWindowClosing <> WindowClosing, use implemented method from API
public void windowClosing(WindowEvent e) {
2) I'b preferred DefaultCloseOperations(JFrame.HIDE_ON_CLOSE),
3) use JDialog instead of JFrame
import javax.swing.*;
import java.awt.*;
import java.awt.event.*;
public class ClosingFrame extends JFrame {
private JMenuBar MenuBar = new JMenuBar();
private static JFrame frame = new JFrame();
private static JFrame frame1 = new JFrame("DefaultCloseOperation(JFrame.HIDE_ON_CLOSE)");
private static final long serialVersionUID = 1L;
private JMenu File = new JMenu("File");
private JMenuItem Exit = new JMenuItem("Exit");
public ClosingFrame() {
File.add(Exit);
MenuBar.add(File);
Exit.addActionListener(new ExitListener());
WindowListener exitListener = new WindowAdapter() {
#Override
public void windowClosing(WindowEvent e) {
frame.setVisible(false);
/*int confirm = JOptionPane.showOptionDialog(frame,
"Are You Sure to Close this Application?",
"Exit Confirmation", JOptionPane.YES_NO_OPTION,
JOptionPane.QUESTION_MESSAGE, null, null, null);
if (confirm == JOptionPane.YES_OPTION) {
System.exit(1);
}*/
}
};
JButton btn = new JButton("Show second JFrame");
btn.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent e) {
frame1.setVisible(true);
}
});
frame.add(btn, BorderLayout.SOUTH);
frame.addWindowListener(exitListener);
frame.setDefaultCloseOperation(JFrame.HIDE_ON_CLOSE);
frame.setJMenuBar(MenuBar);
frame.setPreferredSize(new Dimension(400, 300));
frame.setLocation(100, 100);
frame.pack();
frame.setVisible(true);
}
private class ExitListener implements ActionListener {
#Override
public void actionPerformed(ActionEvent e) {
int confirm = JOptionPane.showOptionDialog(frame,
"Are You Sure to Close this Application?",
"Exit Confirmation", JOptionPane.YES_NO_OPTION,
JOptionPane.QUESTION_MESSAGE, null, null, null);
if (confirm == JOptionPane.YES_OPTION) {
System.exit(1);
}
}
}
public static void main(String[] args) {
SwingUtilities.invokeLater(new Runnable() {
#Override
public void run() {
ClosingFrame cf = new ClosingFrame();
JButton btn = new JButton("Show first JFrame");
btn.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent e) {
frame.setVisible(true);
}
});
frame1.add(btn, BorderLayout.SOUTH);
frame1.setDefaultCloseOperation(JFrame.HIDE_ON_CLOSE);
frame1.setPreferredSize(new Dimension(400, 300));
frame1.setLocation(100, 400);
frame1.pack();
frame1.setVisible(true);
}
});
}
}

Adding a New Code with no WindowListener part as explained by #JBNizet, the very right thing. The default behaviour just hides the window, nothing is lost, you simply have to bring it back, every value inside it will remain as is, below is the sample program for further help :
import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
public class TwoFrames
{
private SecondFrame secondFrame;
private int count = 0;
private void createAndDisplayGUI()
{
JFrame frame = new JFrame("JFRAME 1");
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.setLocationByPlatform(true);
secondFrame = new SecondFrame();
secondFrame.createAndDisplayGUI();
secondFrame.tfield.setText("I will be same everytime.");
JPanel contentPane = new JPanel();
JButton showButton = new JButton("SHOW JFRAME 2");
showButton.addActionListener(new ActionListener()
{
public void actionPerformed(ActionEvent ae)
{
secondFrame.tfield.setText(secondFrame.tfield.getText() + count);
count++;
if (!(secondFrame.isShowing()))
secondFrame.setVisible(true);
}
});
frame.add(contentPane, BorderLayout.CENTER);
frame.add(showButton, BorderLayout.PAGE_END);
frame.setSize(200, 200);
frame.setVisible(true);
}
public static void main(String... args)
{
SwingUtilities.invokeLater(new Runnable()
{
public void run()
{
new TwoFrames().createAndDisplayGUI();
}
});
}
}
class SecondFrame extends JFrame
{
private WindowAdapter windowAdapter;
public JTextField tfield;
public void createAndDisplayGUI()
{
setLocationByPlatform(true);
JPanel contentPane = new JPanel();
tfield = new JTextField(10);
addWindowListener(windowAdapter);
contentPane.add(tfield);
getContentPane().add(contentPane);
setSize(300, 300);
}
}
Is this what you want, try this code :
import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
public class TwoFrames
{
private SecondFrame secondFrame;
private void createAndDisplayGUI()
{
JFrame frame = new JFrame("JFRAME 1");
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.setLocationByPlatform(true);
secondFrame = new SecondFrame();
secondFrame.createAndDisplayGUI();
secondFrame.tfield.setText("I will be same everytime.");
JPanel contentPane = new JPanel();
JButton showButton = new JButton("SHOW JFRAME 2");
showButton.addActionListener(new ActionListener()
{
public void actionPerformed(ActionEvent ae)
{
if (!(secondFrame.isShowing()))
secondFrame.setVisible(true);
}
});
frame.add(contentPane, BorderLayout.CENTER);
frame.add(showButton, BorderLayout.PAGE_END);
frame.setSize(200, 200);
frame.setVisible(true);
}
public static void main(String... args)
{
SwingUtilities.invokeLater(new Runnable()
{
public void run()
{
new TwoFrames().createAndDisplayGUI();
}
});
}
}
class SecondFrame extends JFrame
{
private WindowAdapter windowAdapter;
public JTextField tfield;
public void createAndDisplayGUI()
{
setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
setLocationByPlatform(true);
JPanel contentPane = new JPanel();
tfield = new JTextField(10);
windowAdapter = new WindowAdapter()
{
public void windowClosing(WindowEvent we)
{
setDefaultCloseOperation(JFrame.HIDE_ON_CLOSE);
}
};
addWindowListener(windowAdapter);
contentPane.add(tfield);
getContentPane().add(contentPane);
setSize(300, 300);
}
}

You could avoid the listener completely and use
setDefaultCloseOperation(DISPOSE_ON_CLOSE);
Note that the default value is HIDE_ON_CLOSE, so the behavior you want should be the default behavior. Maybe you registered another listener that exits the application.
See http://docs.oracle.com/javase/6/docs/api/javax/swing/JFrame.html#setDefaultCloseOperation%28int%29

It's hard to pinpoint exactly why you are experiencing the behavior stated without seeing a little more of the set-up code, however it may be due to defaultCloseOperation set to EXIT_ON_CLOSE.
Here's a link to a demo displaying the properties you are looking for although the structure is a bit different. Have a look: http://docs.oracle.com/javase/tutorial/uiswing/examples/components/FrameworkProject/src/components/Framework.java

How to set BackGround color to a divider in JSplitPane

I have created a divider in JSplitPane. I am unable to set the color of divider. I want to set the color of divider. Please help me how to set color of that divider.
import javax.swing.*;
import java.awt.*;
import java.awt.event.*;
public class SplitPaneDemo {
JFrame frame;
JPanel left, right;
JSplitPane pane;
int lastDividerLocation = -1;
public static void main(String[] args) {
SplitPaneDemo demo = new SplitPaneDemo();
demo.makeFrame();
demo.frame.addWindowListener(new WindowAdapter() {
public void windowClosing(WindowEvent e) {
System.exit(0);
}
});
demo.frame.show();
}
public JFrame makeFrame() {
frame = new JFrame();
// Create a horizontal split pane.
pane = new JSplitPane(JSplitPane.HORIZONTAL_SPLIT);
left = new JPanel();
left.setBackground(Color.red);
pane.setLeftComponent(left);
right = new JPanel();
right.setBackground(Color.green);
pane.setRightComponent(right);
JButton showleft = new JButton("Left");
showleft.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent e) {
Container c = frame.getContentPane();
if (pane.isShowing()) {
lastDividerLocation = pane.getDividerLocation();
}
c.remove(pane);
c.remove(left);
c.remove(right);
c.add(left, BorderLayout.CENTER);
c.validate();
c.repaint();
}
});
JButton showright = new JButton("Right");
showright.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent e) {
Container c = frame.getContentPane();
if (pane.isShowing()) {
lastDividerLocation = pane.getDividerLocation();
}
c.remove(pane);
c.remove(left);
c.remove(right);
c.add(right, BorderLayout.CENTER);
c.validate();
c.repaint();
}
});
JButton showboth = new JButton("Both");
showboth.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent e) {
Container c = frame.getContentPane();
c.remove(pane);
c.remove(left);
c.remove(right);
pane.setLeftComponent(left);
pane.setRightComponent(right);
c.add(pane, BorderLayout.CENTER);
if (lastDividerLocation >= 0) {
pane.setDividerLocation(lastDividerLocation);
}
c.validate();
c.repaint();
}
});
JPanel buttons = new JPanel();
buttons.setLayout(new GridBagLayout());
buttons.add(showleft);
buttons.add(showright);
buttons.add(showboth);
frame.getContentPane().add(buttons, BorderLayout.NORTH);
pane.setPreferredSize(new Dimension(400, 300));
frame.getContentPane().add(pane, BorderLayout.CENTER);
frame.pack();
pane.setDividerLocation(0.5);
return frame;
}
}
Thanks
Sunil kumar Sahoo

Or, since the divider is a container, you can do the following:
dividerContainer = (BasicSplitPaneDivider) splitPane.getComponent(2);
Component leftBtn = dividerContainer.getComponent(0);
Component rightBtn = dividerContainer.getComponent(1);
dividerContainer.setBackground(Color.white);
dividerContainer.setBorder(BorderFactory.createEmptyBorder(0, 4, 0, 4));
dividerContainer.setLayout(new FlowLayout(FlowLayout.CENTER, 0, 0));
dividerContainer.add(toolbar);
dividerContainer.setDividerSize(toolbar.getPreferredSize().height);

This code works for me:
splitPane.setUI(new BasicSplitPaneUI() {
public BasicSplitPaneDivider createDefaultDivider() {
return new BasicSplitPaneDivider(this) {
public void setBorder(Border b) {
}
#Override
public void paint(Graphics g) {
g.setColor(Color.GREEN);
g.fillRect(0, 0, getSize().width, getSize().height);
super.paint(g);
}
};
}
});
splitPane.setBorder(null);
You can change divider color "g.setColor(new Color(R,G,B))".

This worked for me fine.First you are creating JFrame with it's normal methods such as setDefaultCloseOperation(), setBounds(), getContentPane(). Then create an object from your class then use that to call all the other methods through out the program, in this case I created object called app. One thing you have to keep in mind is that don't forget to use ActionListener e.
Also color changes must go with setBackground() function, while you getting the values from getSource() for the color change.
import javax.swing.*;
import java.awt.event.*;
import java.awt.*;
public class Main implements ActionListener {
private static void createAndShowGUI() {
Main app=new Main();
// make frame..
JFrame.setDefaultLookAndFeelDecorated(true);
JFrame frame = new JFrame("I am a JFrame");
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.setBounds(20,30,300,120);
frame.setLayout(null);
//Create a split pane
JSplitPane myPane = new JSplitPane();
myPane.setOpaque(true);
myPane.setDividerLocation(150);
app.right = new JPanel();
app.right.setBackground(new Color(255,0,0));
app.left = new JPanel();
app.left.setBackground(new Color(0,255,0));
app.left.setLayout(null);
myPane.setRightComponent(app.right);
myPane.setLeftComponent(app.left);
// make buttons
app.butt1=new JButton("Red");
app.butt2=new JButton("Blue");
app.butt3=new JButton("Green");
// add and size buttons
app.left.add(app.butt1);
app.butt1.setBounds(10,10, 100,20);
app.left.add(app.butt2);
app.butt2.setBounds(10,30, 100,20);
app.left.add(app.butt3);
app.butt3.setBounds(10,50, 100,20);
// set up listener
app.butt1.addActionListener(app);
app.butt2.addActionListener(app);
app.butt3.addActionListener(app);
frame.setContentPane(myPane);
frame.setVisible(true);
}
public void actionPerformed(ActionEvent e)
{
// check which button and act accordingly
if (e.getSource()==butt1)
right.setBackground(new Color(255,0,0));
if (e.getSource()==butt2)
right.setBackground(new Color(0,0,255));
if (e.getSource()==butt3)
right.setBackground(new Color(0,255,0));
}
public static void main(String[] args) {
// start off..
try {
UIManager.setLookAndFeel(
"javax.swing.plaf.metal.MetalLookAndFeel" );
}
catch (Exception e)
{
System.out.println("Cant get laf");
}
Object a[]= UIManager.getInstalledLookAndFeels();
for (int i=0; i<a.length; i++)
System.out.println(a[i]);
SwingUtilities.invokeLater(new Runnable() {
public void run() {
createAndShowGUI();
}
});
}
// application object fields
int clickCount=0;
JLabel label;
JButton butt1;
JButton butt2;
JButton butt3;
JPanel left;
JPanel right;
}