I am dynamically adding items to my JPanel through an ArrayList<Items>. Basically the items object looks like that:
public class Item {
private JComponent component;
private String functionality;
public Item(JComponent component, String functionality) {
super();
this.component = component;
this.functionality = functionality;
}
public JComponent getComponent() {
return component;
}
public void setComponent(JComponent component) {
this.component = component;
}
public String getFunctionality() {
return functionality;
}
public void setFunctionality(String functionality) {
this.functionality = functionality;
}
}
Here I am adding my buttons dynamically: (try the example out if you want)
public class minimumExample extends JFrame {
private JButton addItem;
private JComboBox itemBox;
private String[] itemSelect = { "test1", "test2" };
private JPanel addUpperPane;
private JPanel addLowerPane;
private ArrayList<Item> displayedItems = new ArrayList<Item>();
private JButton upButton;
private JButton downButton;
private JButton deleteButton;
public void createControlPane() {
addUpperPane = new JPanel();
addLowerPane = new JPanel(new GridLayout(0, 1));
addItem = new JButton("Add item");
upButton = new JButton("Up");
downButton = new JButton("Down");
deleteButton = new JButton("Delete");
itemBox = new JComboBox(itemSelect);
addItem.addActionListener(new ActionListener() {
#Override
public void actionPerformed(ActionEvent e) {
if(itemBox.getSelectedItem().toString().equals("test1")) {
displayedItems.add(new Item( new ButtonComp().butt(), "test1"));
validate();
repaint();
}
if(itemBox.getSelectedItem().toString().equals("test2")) {
displayedItems.add(new Item( new LabelComp().label(), "test2"));
validate();
repaint();
}
for (int i = 0; i < displayedItems.size(); i++) {
addLowerPane.add(displayedItems.get(i).getComponent());
validate();
repaint();
}
}
});
addUpperPane.add(itemBox, BorderLayout.EAST);
addUpperPane.add(addItem, BorderLayout.WEST);
addUpperPane.add(new JLabel(" | "), BorderLayout.WEST);
addUpperPane.add(upButton, BorderLayout.WEST);
addUpperPane.add(downButton, BorderLayout.WEST);
addUpperPane.add(deleteButton, BorderLayout.WEST);
addUpperPane.add(new JSeparator(JSeparator.HORIZONTAL));
//put everything together
add(addUpperPane, BorderLayout.NORTH);
add(addLowerPane, BorderLayout.SOUTH);
repaint();
}
private void makeLayout() {
setTitle("Test App");
setLayout(new BorderLayout());
setPreferredSize(new Dimension(1000, 500));
createControlPane();
setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
pack();
setVisible(true);
}
/**
* starts the GUI
*/
public void start() {
javax.swing.SwingUtilities.invokeLater(new Runnable() {
public void run() {
makeLayout();
}
});
}
public static void main(String[] args) throws IOException {
minimumExample ex = new minimumExample();
ex.start();
}
public class ButtonComp extends Component {
public JPanel butt() {
JPanel panel = new JPanel();
JButton button = new JButton("Test1");
JCheckBox check = new JCheckBox();
panel.add(button);
panel.add(check);
return panel;
}
}
public class LabelComp extends Component {
public JPanel label() {
JPanel panel = new JPanel();
JLabel label = new JLabel("Test2");
JCheckBox check = new JCheckBox();
panel.add(label);
panel.add(check);
return panel;
}
}
}
The program basically looks like that:
My problem is that the buttons Up, Down and Delete do not work, because I do not know how to get the selected element from the pane to delete it from the list where all components are in. Any recommendations on how to make this work?
I really appreciate your answer!
UPDATE
I changed my code your specifications #cghislai but it does not work. Try it out yourself:
import java.awt.BorderLayout;
import java.awt.Component;
import java.awt.Dimension;
import java.awt.GridLayout;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.io.IOException;
import java.util.ArrayList;
import java.util.Iterator;
import java.util.List;
import javax.swing.JButton;
import javax.swing.JCheckBox;
import javax.swing.JComboBox;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JPanel;
import javax.swing.JSeparator;
public class minimumExample extends JFrame {
private JButton addItem;
private JComboBox itemBox;
private String[] itemSelect = { "test1", "test2" };
private JPanel addUpperPane;
private JPanel addLowerPane;
private List<CheckableItem> displayedItems = new ArrayList<CheckableItem>();
private JButton upButton;
private JButton downButton;
private JButton deleteButton;
public void createControlPane() {
addUpperPane = new JPanel();
addLowerPane = new JPanel(new GridLayout(0, 1));
addItem = new JButton("Add item");
upButton = new JButton("Up");
downButton = new JButton("Down");
deleteButton = new JButton("Delete");
itemBox = new JComboBox(itemSelect);
addItem.addActionListener(new ActionListener() {
#Override
public void actionPerformed(ActionEvent e) {
if(itemBox.getSelectedItem().toString().equals("test1")) {
ButtonComp butt = new ButtonComp();
butt.init();
displayedItems.add(butt);
validate();
repaint();
}
if(itemBox.getSelectedItem().toString().equals("test2")) {
// displayedItems.add(new CopyOfItem( new LabelComp(), "test2"));
validate();
repaint();
}
for (int i = 0; i < displayedItems.size(); i++) {
addLowerPane.add(displayedItems.get(i).getComponent());
validate();
repaint();
}
}
});
deleteButton.addActionListener(new ActionListener() {
#Override
public void actionPerformed(ActionEvent arg0) {
Iterator<CheckableItem> it = displayedItems.iterator();
while (it.hasNext()) {
CheckableItem next = it.next();
if (next.isSelected()) {
addLowerPane.remove(next.getComponent());
it.remove();
continue;
}
}
}
});
addUpperPane.add(itemBox, BorderLayout.EAST);
addUpperPane.add(addItem, BorderLayout.WEST);
addUpperPane.add(new JLabel(" | "), BorderLayout.WEST);
addUpperPane.add(upButton, BorderLayout.WEST);
addUpperPane.add(downButton, BorderLayout.WEST);
addUpperPane.add(deleteButton, BorderLayout.WEST);
addUpperPane.add(new JSeparator(JSeparator.HORIZONTAL));
//put everything together
add(addUpperPane, BorderLayout.NORTH);
add(addLowerPane, BorderLayout.SOUTH);
repaint();
}
private void makeLayout() {
setTitle("Test App");
setLayout(new BorderLayout());
setPreferredSize(new Dimension(1000, 500));
createControlPane();
setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
pack();
setVisible(true);
}
/**
* starts the GUI
*/
public void start() {
javax.swing.SwingUtilities.invokeLater(new Runnable() {
public void run() {
makeLayout();
}
});
}
public static void main(String[] args) throws IOException {
minimumExample ex = new minimumExample();
ex.start();
}
public abstract class CheckableItem {
protected JCheckBox check;
public boolean isSelected() {
return check.isSelected();
}
public abstract Component getComponent();
}
public class ButtonComp extends CheckableItem {
JPanel panel = new JPanel();
public void init() {
JButton button = new JButton("Test1");
check = new JCheckBox();
panel.add(button);
panel.add(check);
}
#Override
public Component getComponent() {
return panel;
}
}
public class LabelComp extends JPanel {
public void label() {
// JPanel panel = new JPanel();
JLabel label = new JLabel("Test2");
JCheckBox check = new JCheckBox();
add(label);
add(check);
}
}
}
You need to traverse all your items, check if the item checkbox is selected, if this is the case, remove your item from the panel. I would make an abstract CheckableItem class with a getter to the JCheckbox and the Component. Then, for each of you item, if the checkbox is selected, remove the component from the parent.
public abstract class CheckableItem {
protected JCheckbox checkbox;
public boolean isSelected() {
return checkbox.isSelected();
}
public abstract Component getComponent();
}
public class ButtonComp extends CheckableItem {
private Panel panel;
public void init() {
checkbox = new JCheckbox;
panel = new JPanel();
panel.add(new JButton());
panel.add(checkbox);
}
public Component getComponent() {
return panel;
}
}
Then to keep track of your items:
private List<CheckableItem> items = new ArrayList<>();
// ...
ButtonComp comp = new ButtonComp();
comp.init();
items.add(comp);
Then to remove all checked:
Iterator<CheckbleItem> it = items.iterator();
while (it.hasNext()) {
CheckableItem next = it.next();
if (next.isSelected()) {
mainPanel.remove(next.getComponent());
it.remove();
continue;
}
}
Why don't you just have your ButtomComp and LabelComp extend from JPanel? This would solve a lot of your problems I think. For example :
public class ButtonComp extends JPanel {
JButton button;
JCheckBox check = new JCheckBox();
public ButtonComp() {
button = new JButton("Test1");
this.add(button);
this.add(check);
}
}
Then all you would need to do is iterate over your items and look at the checkbox in the components :
for (int i = 0; i < displayedItems.size(); i++) {
if (displayedItems.get(i).check.isSelected()) {
displayedItems.remove(i);
}
}
Note: haven't tested this code. But you should get the idea.
Related
So I'm working on making a database system built on top of a Java Swing GUI... I have one button that works to add a person/thing to a vector (in this case the database):
// Database
Vector<String> db = new Vector<String>();
Here is the button's actionlistener to add:
new ActionListener() {
public void actionPerformed(ActionEvent e) {
String newStudent = student.getText();
db.addElement(newStudent);
This part all seems to be working fine, however, when I go to print out the vector on a JTextArea using a string buffer, there are odd spacing issues in the text on the JTextArea
Here is the StringBuffer and section where I print the vector onto the JTextArea:
StringBuffer dbb = new StringBuffer();
for (int i = 0; i < db.size(); i++) {
dbb.append(db.get(i) + '\n');
}
// printDB is the JTextArea
printDB.setText(dbb.toString());
add(printDB);
Screenshot of spacing issues:
Screenshot
Any Ideas on what might be causing this? The spacing seems to be linear as well (1space, 2spaces, 3spaces...)
Link to full project if needed (Sorry for bad code in general lol i'm just beginning): Full Code
Sorry if linear isn't the right word btw I couldn't think of another way to describe it
Code:
import java.awt.*;
import java.awt.event.*;
import java.io.IOException;
import java.util.*;
import java.util.Vector.*;
import javax.swing.*;
public class Database extends JFrame implements ActionListener, EventListener {
// Database
Vector<String> db = new Vector<String>();
// Main Menu Buttons:
JButton addStudent = new JButton("Add Student");
JButton deleteStudent = new JButton("Delete Button");
JButton deleteAll = new JButton("Delete All Students");
JButton printAll = new JButton("Print Database");
JTextArea welcome = new JTextArea("Welcome!");
// Add Student Menu:
JTextField student = new JTextField();
JButton submit = new JButton("Add Student");
// Print Students
JTextArea printDB = new JTextArea();
JButton returnMenu = new JButton("Return to Menu");
public Database() {
super("DatabaseGUI");
setSize(800, 600);
setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
setLayout(null);
setResizable(false);
welcome.setBackground(this.getForeground());
add(welcome);
welcome.setSize(60, 15);
welcome.setLocation(386, 300);
add(addStudent);
addStudent.setSize(150, 50);
addStudent.setLocation(25, 100);
add(deleteStudent);
deleteStudent.setSize(150, 50);
deleteStudent.setLocation(625, 100);
add(deleteAll);
deleteAll.setLocation(225, 100);
deleteAll.setSize(150, 50);
add(printAll);
printAll.setLocation(425, 100);
printAll.setSize(150, 50);
addStudent.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent e) {
welcome.setVisible(false);
addStudent.setVisible(false);
deleteStudent.setVisible(false);
deleteAll.setVisible(false);
printAll.setVisible(false);
add(student);
add(submit);
submit.setVisible(true);
submit.setSize(150, 30);
submit.setLocation(425, 250);
student.setVisible(true);
student.setSize(150, 30);
student.setLocation(275, 250);
submit.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent e) {
String newStudent = student.getText();
db.addElement(newStudent);
student.setText(null);
student.setVisible(false);
submit.setVisible(false);
welcome.setVisible(true);
addStudent.setVisible(true);
deleteStudent.setVisible(true);
deleteAll.setVisible(true);
printAll.setVisible(true);
}
});
}
});
printAll.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent e) {
welcome.setVisible(false);
addStudent.setVisible(false);
deleteStudent.setVisible(false);
deleteAll.setVisible(false);
printAll.setVisible(false);
StringBuffer dbb = new StringBuffer();
for (int i = 0; i < db.size(); i++) {
dbb.append(db.get(i) + '\n');
}
printDB.setText(dbb.toString());
add(printDB);
printDB.setSize(300, 400);
printDB.setEditable(false);
printDB.setLocation(100, 100);
printDB.setVisible(true);
add(returnMenu);
returnMenu.setVisible(true);
returnMenu.setSize(200, 30);
returnMenu.setLocation(500, 400);
returnMenu.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent e) {
returnMenu.setVisible(false);
printDB.setVisible(false);
welcome.setVisible(true);
addStudent.setVisible(true);
deleteStudent.setVisible(true);
deleteAll.setVisible(true);
printAll.setVisible(true);
}
});
}
});
setVisible(true);
}
public static void main(String[] args) {
Database student = new Database();
}
#Override
public void actionPerformed(ActionEvent e) {
// TODO Auto-generated method stub
}
}
You're adding an ActionListener to the submit button repeatedly within the addStudent ActionListener, meaning as addStudent is pressed, more and more ActionListeners will be added to submit and this is not what you want.
Suggestions:
Add an ActionListener just once to your JButtons and not within other event listeners which may be called multiple times. Consider adding all ActionListeners within your class constructor.
Side recs:
Don't use absolute positioning and null layouts. While null layouts and setBounds() might seem to Swing newbies like the easiest and best way to create complex GUI's, the more Swing GUI'S you create the more serious difficulties you will run into when using them. They won't resize your components when the GUI resizes, they are a royal witch to enhance or maintain, they fail completely when placed in scrollpanes, they look gawd-awful when viewed on all platforms or screen resolutions that are different from the original one.
Learn how to use and then use CardLayout to allow you to cleanly and easily swap your views.
For example,
import java.awt.BorderLayout;
import java.awt.CardLayout;
import java.awt.Font;
import java.awt.GridLayout;
import java.awt.Window;
import java.awt.event.ActionEvent;
import java.awt.event.KeyEvent;
import java.util.ArrayList;
import java.util.List;
import javax.swing.*;
#SuppressWarnings("serial")
public class Database2 extends JPanel {
// constants for the cards
public static final String WELCOME = "welcome";
public static final String ADD_STUDENT = "add student";
public static final String DISPLAY_DATA = "display data";
private JTextArea displayTextArea = new JTextArea(15, 20);
private JTextField addStudentField = new JTextField(10);
private CardLayout cardLayout = new CardLayout();
private List<String> db = new ArrayList<>();
public Database2() {
// prepare JTextArea
displayTextArea.setWrapStyleWord(true);
displayTextArea.setLineWrap(true);
displayTextArea.setFocusable(false);
// set layout as CardLayout and add all JPanels with constants
setLayout(cardLayout);
add(createWelcomePanel(), WELCOME);
add(createAddStudentPanel(), ADD_STUDENT);
add(createDisplayDataPanel(), DISPLAY_DATA);
}
private JPanel createWelcomePanel() {
ShowStudentPanelAction showStudentAction = new ShowStudentPanelAction("Add Student");
DisplayDataAction displayDataAction = new DisplayDataAction("Display Data");
JButton addStudentButton = new JButton(showStudentAction);
JButton displayDataButton = new JButton(displayDataAction);
JPanel topPanel = new JPanel(new GridLayout(1, 0, 5, 0));
topPanel.add(addStudentButton);
topPanel.add(displayDataButton);
topPanel.add(new JButton(new ExitAction("Exit", KeyEvent.VK_X)));
JLabel welcomeLabel = new JLabel("Welcome", SwingConstants.CENTER);
// make JLabel text bigger
welcomeLabel.setFont(welcomeLabel.getFont().deriveFont(Font.BOLD, 42f));
// and give it a border 30 points wide
int ebGap = 30;
welcomeLabel.setBorder(BorderFactory.createEmptyBorder(ebGap, ebGap,
ebGap, ebGap));
JPanel welcomePanel = new JPanel(new BorderLayout());
ebGap = 4;
welcomePanel.setBorder(BorderFactory.createEmptyBorder(ebGap, ebGap, ebGap, ebGap));
welcomePanel.add(topPanel, BorderLayout.PAGE_START);
welcomePanel.add(welcomeLabel, BorderLayout.CENTER);
return welcomePanel;
}
private JPanel createAddStudentPanel() {
AddStudentAction addStudentAction = new AddStudentAction("Add Student");
addStudentField.setAction(addStudentAction);
JPanel addStudentPanel = new JPanel();
addStudentPanel.add(addStudentField);
addStudentPanel.add(new JButton(addStudentAction));
return addStudentPanel;
}
private JPanel createDisplayDataPanel() {
JPanel displayDataPanel = new JPanel();
JScrollPane scrollPane = new JScrollPane(displayTextArea);
scrollPane.setVerticalScrollBarPolicy(JScrollPane.VERTICAL_SCROLLBAR_ALWAYS);
displayDataPanel.add(scrollPane);
displayDataPanel.add(new JButton(new ReturnToWelcomeAction("Return")));
return displayDataPanel;
}
private class ShowStudentPanelAction extends AbstractAction {
public ShowStudentPanelAction(String name) {
super(name);
int mnemonic = (int) name.charAt(0);
putValue(MNEMONIC_KEY, mnemonic);
}
#Override
public void actionPerformed(ActionEvent e) {
cardLayout.show(Database2.this, ADD_STUDENT);
addStudentField.requestFocusInWindow();
addStudentField.selectAll();
}
}
private class DisplayDataAction extends AbstractAction {
public DisplayDataAction(String name) {
super(name);
int mnemonic = (int) name.charAt(0);
putValue(MNEMONIC_KEY, mnemonic);
}
#Override
public void actionPerformed(ActionEvent e) {
StringBuilder sb = new StringBuilder();
for (String studentName : db) {
sb.append(studentName + "\n");
}
displayTextArea.setText(sb.toString());
cardLayout.show(Database2.this, DISPLAY_DATA);
}
}
private class AddStudentAction extends AbstractAction {
public AddStudentAction(String name) {
super(name);
int mnemonic = (int) name.charAt(0);
putValue(MNEMONIC_KEY, mnemonic);
}
#Override
public void actionPerformed(ActionEvent e) {
String studentText = addStudentField.getText();
db.add(studentText);
cardLayout.show(Database2.this, WELCOME);
}
}
private class ReturnToWelcomeAction extends AbstractAction {
public ReturnToWelcomeAction(String name) {
super(name);
int mnemonic = (int) name.charAt(0);
putValue(MNEMONIC_KEY, mnemonic);
}
#Override
public void actionPerformed(ActionEvent e) {
cardLayout.show(Database2.this, WELCOME);
}
}
private class ExitAction extends AbstractAction {
public ExitAction(String name, int mnemonic) {
super(name);
putValue(MNEMONIC_KEY, mnemonic);
}
#Override
public void actionPerformed(ActionEvent e) {
Window window = SwingUtilities.getWindowAncestor(Database2.this);
if (window != null) {
window.dispose();
}
}
}
private static void createAndShowGui() {
Database2 mainPanel = new Database2();
JFrame frame = new JFrame("Database2");
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();
}
});
}
}
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.
public class MainWindow extends JPanel {
public static MainWindow instance = new MainWindow();
private CardLayout cards = new CardLayout();
public MainWindow() {
setLayout(cards);
add(new FirstPage(), Pages.FIRST.toString());
add(new SecondPage(), Pages.SECOND.toString());
add(new ThirdPage(), Pages.THIRD.toString());
}
public void showPage(Pages page) {
cards.show(this, page.toString());
}
}
the showPage(page); method works fine if I call it in the constructor of MainWindow. But when I try to call MainWindow.instance.showPage(Pages.SECOND); from an ActionListener in FirstPage nothing happens. I've checked that the showPage(page) method works correctly. I've checked that the ActionEvent is fired and enters the correct if/else clause. What am I doing wrong, why isn't my second page showing?
public class FirstPage extends JPanel {
private JButton showSecond = new JButton("Show Second");
private JButton showThird = new JButton("Show Third");
public FirstPage() {
insertButton(showSecond);
insertButton(showThird);
}
private void insertButton(JButton button) {
button.addActionListener(new ActionListener() {
#Override
public void actionPerformed(ActionEvent e) {
if (e.getSource() == showSecond) {
MainWindow.instance.showPage(Pages.SECOND);
} else {
MainWindow.instance.showPage(Pages.THIRD);
}
}
});
this.add(button);
}
}
It would suggest a reference issue. public static MainWindow instance = new MainWindow(); looks suspicious, as you would have had to create an instance of MainWindow first for it to be initialise which suggests you now have two instances of MainWindow, one on the screen and one that is not
Using static in this way is a bad idea, as it leads to issues like this. Instead you should pass a reference of the controller to the page. The controller would define the actions that each page could perform (and if done right, would be defined as an interface)
Alternatively, you could separate the navigation from the pages into a separate mechanism, this means the pages don't care and can simply displayed in any order you want or reused else where
Example #1 - Controller based pages
This examples defines a simple controller which the pages can call in order to effect the navigation of the pages
import java.awt.BorderLayout;
import java.awt.CardLayout;
import java.awt.EventQueue;
import java.awt.FlowLayout;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.util.ArrayList;
import java.util.List;
import javax.swing.JButton;
import javax.swing.JComponent;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JPanel;
import javax.swing.UIManager;
import javax.swing.UnsupportedLookAndFeelException;
public class CardLayoutExample {
public static void main(String[] args) {
new CardLayoutExample();
}
public CardLayoutExample() {
EventQueue.invokeLater(new Runnable() {
#Override
public void run() {
try {
UIManager.setLookAndFeel(UIManager.getSystemLookAndFeelClassName());
} catch (ClassNotFoundException | InstantiationException | IllegalAccessException | UnsupportedLookAndFeelException ex) {
}
JFrame frame = new JFrame("Testing");
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.setLayout(new BorderLayout());
frame.add(new Wizard());
frame.pack();
frame.setLocationRelativeTo(null);
frame.setVisible(true);
}
});
}
public interface NavigationController {
public void nextPage();
public void previousPage();
public void lastPage();
public void firstPage();
}
public interface Page {
public NavigationController getNavigationController();
public JComponent getView();
public String getName();
}
public class Wizard extends JPanel implements NavigationController {
private List<Page> pages;
private Page currentPage;
private CardLayout cardLayout;
public Wizard() {
cardLayout = new CardLayout();
pages = new ArrayList<>(25);
setLayout(cardLayout);
pages.add(new FirstPage("Page01", this));
pages.add(new SecondPage("Page02", this));
pages.add(new ThirdPage("Page03", this));
for (Page page : pages) {
add(page.getView(), page.getName());
}
firstPage();
}
#Override
public void nextPage() {
int index = pages.indexOf(currentPage);
index++;
if (index < pages.size()) {
cardLayout.next(this);
currentPage = pages.get(index);
}
}
#Override
public void previousPage() {
int index = pages.indexOf(currentPage);
index--;
if (index >= 0) {
cardLayout.previous(this);
currentPage = pages.get(index);
}
}
#Override
public void lastPage() {
Page page = pages.get(pages.size() - 1);
showPage(page);
}
#Override
public void firstPage() {
Page page = pages.get(0);
showPage(page);
}
protected void showPage(Page page) {
cardLayout.show(this, page.getName());
currentPage = page;
}
}
public abstract class AbstractPage extends JPanel implements Page, ActionListener {
private NavigationController navigationController;
private JPanel buttons;
private String name;
public AbstractPage(String name, NavigationController navigationController) {
this.name = name;
this.navigationController = navigationController;
setLayout(new BorderLayout());
buttons = new JPanel(new FlowLayout(FlowLayout.RIGHT));
add(buttons, BorderLayout.SOUTH);
}
protected void insertButton(JButton button) {
button.addActionListener(this);
buttons.add(button);
}
#Override
public NavigationController getNavigationController() {
return navigationController;
}
#Override
public JComponent getView() {
return this;
}
#Override
public String getName() {
return super.getName();
}
}
public class FirstPage extends AbstractPage implements Page {
private JButton next = new JButton("Next >");
public FirstPage(String name, NavigationController controller) {
super(name, controller);
JLabel label = new JLabel("First page");
label.setHorizontalAlignment(JLabel.CENTER);
add(label);
insertButton(next);
}
#Override
public void actionPerformed(ActionEvent e) {
if (e.getSource() == next) {
getNavigationController().nextPage();
}
}
}
public class SecondPage extends AbstractPage implements Page {
private JButton next = new JButton("Next >");
private JButton previous = new JButton("< Previous");
public SecondPage(String name, NavigationController controller) {
super(name, controller);
JLabel label = new JLabel("Second page");
label.setHorizontalAlignment(JLabel.CENTER);
add(label);
insertButton(previous);
insertButton(next);
}
#Override
public void actionPerformed(ActionEvent e) {
if (e.getSource() == next) {
getNavigationController().nextPage();
} else if (e.getSource() == previous) {
getNavigationController().previousPage();
}
}
}
public class ThirdPage extends AbstractPage implements Page {
private JButton previous = new JButton("< Previous");
public ThirdPage(String name, NavigationController controller) {
super(name, controller);
JLabel label = new JLabel("Third page");
label.setHorizontalAlignment(JLabel.CENTER);
add(label);
insertButton(previous);
}
#Override
public void actionPerformed(ActionEvent e) {
if (e.getSource() == previous) {
getNavigationController().previousPage();
}
}
}
}
Example #2 - central controller example
This example separates the controller from the pages, so that the buttons are not part of the pages themselves. This frees up the pages/views to be anything you need them to be
import java.awt.BorderLayout;
import java.awt.CardLayout;
import java.awt.Component;
import java.awt.EventQueue;
import java.awt.GridBagConstraints;
import java.awt.GridBagLayout;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JPanel;
import javax.swing.UIManager;
import javax.swing.UnsupportedLookAndFeelException;
import javax.swing.border.EmptyBorder;
public class CardLayoutExample2 {
public static void main(String[] args) {
new CardLayoutExample2();
}
public CardLayoutExample2() {
EventQueue.invokeLater(new Runnable() {
#Override
public void run() {
try {
UIManager.setLookAndFeel(UIManager.getSystemLookAndFeelClassName());
} catch (ClassNotFoundException | InstantiationException | IllegalAccessException | UnsupportedLookAndFeelException ex) {
}
JFrame frame = new JFrame("Testing");
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.setLayout(new BorderLayout());
frame.add(new WizardPane());
frame.pack();
frame.setLocationRelativeTo(null);
frame.setVisible(true);
}
});
}
public class WizardPane extends JPanel {
private List<String> pages;
private String currentPage;
private JButton first;
private JButton previous;
private JButton next;
private JButton last;
private CardLayout cardLayout;
private JPanel contentPane;
public WizardPane() {
setLayout(new BorderLayout());
cardLayout = new CardLayout();
pages = new ArrayList<>(3);
contentPane = new JPanel(cardLayout);
contentPane.setBorder(new EmptyBorder(4, 4, 4, 4));
pages.add("Page01");
pages.add("Page02");
pages.add("Page03");
contentPane.add(new FirstPage(), "Page01");
contentPane.add(new SecondPage(), "Page02");
contentPane.add(new ThirdPage(), "Page03");
JPanel actionsPane = new JPanel(new GridBagLayout());
actionsPane.setBorder(new EmptyBorder(4, 4, 4, 4));
GridBagConstraints gbc = new GridBagConstraints();
gbc.gridx = 0;
gbc.gridy = 0;
actionsPane.add((first = new JButton("<< First")), gbc);
gbc.gridx++;
gbc.weightx = 1;
gbc.anchor = GridBagConstraints.WEST;
actionsPane.add((previous = new JButton("< Previous")), gbc);
gbc.gridx++;
gbc.anchor = GridBagConstraints.EAST;
actionsPane.add((next = new JButton("Next >")), gbc);
gbc.gridx++;
gbc.weightx = 0;
actionsPane.add((last = new JButton("Last >>")), gbc);
add(contentPane);
add(actionsPane, BorderLayout.SOUTH);
NavigationHandler handler = new NavigationHandler();
first.addActionListener(handler);
previous.addActionListener(handler);
next.addActionListener(handler);
last.addActionListener(handler);
gotoFirstPage();
}
protected void gotoFirstPage() {
currentPage = pages.get(0);
cardLayout.show(contentPane, currentPage);
}
protected void gotoPreviousPage() {
int index = pages.indexOf(currentPage);
index--;
if (index >= 0) {
currentPage = pages.get(index);
cardLayout.show(contentPane, currentPage);
}
}
protected void gotoNextPage() {
int index = pages.indexOf(currentPage);
index++;
if (index < pages.size()) {
currentPage = pages.get(index);
cardLayout.show(contentPane, currentPage);
}
}
protected void gotoLastPage() {
currentPage = pages.get(pages.size() - 1);
cardLayout.show(contentPane, currentPage);
}
protected class NavigationHandler implements ActionListener {
#Override
public void actionPerformed(ActionEvent e) {
if (e.getSource() == first) {
gotoFirstPage();
} else if (e.getSource() == previous) {
gotoPreviousPage();
} else if (e.getSource() == next) {
gotoNextPage();
} else if (e.getSource() == last) {
gotoLastPage();
}
}
}
}
public class FirstPage extends JPanel {
public FirstPage() {
setLayout(new BorderLayout());
JLabel label = new JLabel("Page One");
label.setHorizontalAlignment(JLabel.CENTER);
add(label);
}
}
public class SecondPage extends JPanel {
public SecondPage() {
setLayout(new BorderLayout());
JLabel label = new JLabel("Page Two");
label.setHorizontalAlignment(JLabel.CENTER);
add(label);
}
}
public class ThirdPage extends JPanel {
public ThirdPage() {
setLayout(new BorderLayout());
JLabel label = new JLabel("Page Three");
label.setHorizontalAlignment(JLabel.CENTER);
add(label);
}
}
}
Example #3 - Model based
Or you could use a model based approach (which is probably more preferable), which defines the order in which components are displayed. For example
I have a JFrame which contains 2 JPanel subclass and 2 JLabel in BorderLayout. One of the JPanel contains JButtons and the other is used for displaying graphics. The JLabels are in north and south, the button JPanel in the west and the display JPanel in center.
The display JPanel requires constant refresh, so i invoke its repaint() method via the action event generated by swing timer. I also override its paintComponent() method to do my drawings.
Instead of displaying what i have drawn, the "content of the JFrame" is being drawn onto the display JPanel. I am aware that i can simply "clear" the display JPanel by using g.fillRect() or super.paintComponent() before doing my drawings.
I am just curious why this happens.
i'm using jdk 1.6u27. below is my code:
package test;
import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
import javax.swing.event.*;
public class Main {
public static void main(String[] args) {
Simulation sim = new Simulation();
}
}
class Simulation extends JFrame {
public JLabel state;
private JLabel id;
private ButtonPanel control;
private Display display;
public Simulation() {
id = new JLabel("Test");
state = new JLabel("Test");
control = new ButtonPanel();
display = new Display(this);
this.setLayout(new BorderLayout());
this.add(id, BorderLayout.NORTH);
this.add(control, BorderLayout.WEST);
this.add(display, BorderLayout.CENTER);
this.add(state, BorderLayout.SOUTH);
this.setSize(500, 600);
this.setVisible(true);
this.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
}
public ButtonPanel getControl() {
return this.control;
}
}
class ButtonPanel extends JPanel implements ActionListener {
public JButton b[] = new JButton[8];
public boolean bp[] = new boolean[8];
public ButtonPanel() {
this.setLayout(new GridLayout(8, 1));
for (int i = 0; i < b.length; i++) {
b[i] = new JButton(""+i);
b[i].addActionListener(this);
bp[i] = false;
this.add(b[i]);
}
}
public void actionPerformed(ActionEvent e) {
//do something
}
}
class Display extends JPanel implements ActionListener {
private Timer tm;
private int yco;
private Simulation sim;
public Display(Simulation sim) {
tm = new Timer(100, this);
tm.start();
yco = 0;
this.sim = sim;
}
#Override
public void paintComponent(Graphics g) {
//draw something
g.drawLine(0, yco, 100, 100);
}
public void actionPerformed(ActionEvent e) {
yco ++;
this.repaint();
}
}
Without super.paintComponent(g), the result depends on your platform's default for the opacity property of the JPanel UI delegate, PanelUI. Mine happens to be true, but you can experiment on your platform, as suggested below.
Addendum: "If you do not honor the opaque property you will likely see visual artifacts."—paintComponent(). The artifact you observe will vary by platform, but it is not atypical. In effect, you are breaking the promise to draw every pixel, and you see whatever is left over in some buffer.
import java.awt.*;
import java.awt.event.*;
import java.util.ArrayList;
import java.util.List;
import javax.swing.*;
public class Main {
public static void main(String[] args) {
EventQueue.invokeLater(new Runnable() {
#Override
public void run() {
Simulation sim = new Simulation();
}
});
}
}
class Simulation extends JFrame {
public JCheckBox state;
private JLabel id;
private ButtonPanel control;
private Display display;
public Simulation() {
id = new JLabel("Test");
state = new JCheckBox("Opaque");
control = new ButtonPanel();
display = new Display(this);
this.setLayout(new BorderLayout());
this.add(id, BorderLayout.NORTH);
this.add(control, BorderLayout.WEST);
this.add(display, BorderLayout.CENTER);
this.add(state, BorderLayout.SOUTH);
state.addItemListener(new ItemListener() {
#Override
public void itemStateChanged(ItemEvent e) {
display.setOpaque(e.getStateChange() == ItemEvent.SELECTED);
}
});
state.setSelected(true);
this.pack();
this.setVisible(true);
this.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
}
public ButtonPanel getControl() {
return this.control;
}
}
class ButtonPanel extends JPanel {
private static final int N = 8;
private List<JToggleButton> list = new ArrayList<JToggleButton>(N);
public ButtonPanel() {
this.setLayout(new GridLayout(0, 1));
for (int i = 0; i < N; i++) {
final JToggleButton b = new JToggleButton(String.valueOf(i));
b.addActionListener(new ActionListener() {
#Override
public void actionPerformed(ActionEvent e) {
//System.out.println(b.isSelected());
}
});
list.add(b);
this.add(b);
}
}
}
class Display extends JPanel {
private Simulation sim;
private Timer tm;
private int yco;
public Display(Simulation sim) {
this.setPreferredSize(new Dimension(320, 320));
this.setOpaque(true);
this.sim = sim;
tm = new Timer(100, new ActionListener() {
#Override
public void actionPerformed(ActionEvent e) {
yco++;
repaint();
}
});
tm.start();
}
#Override
public void paintComponent(Graphics g) {
//super.paintComponent(g);
g.drawLine(0, yco, getWidth() / 2, getHeight() / 2);
}
}
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.