Why JPanel.focusGaind and Lost don't work? - java

Please take a look at the following code (I've missed the imports purposely)
public class MainFrame extends JFrame {
private JPanel contentPane;
public static void main(String[] args) {
EventQueue.invokeLater(new Runnable() {
public void run() {
try {
MainFrame frame = new MainFrame();
frame.setVisible(true);
} catch (Exception e) {
e.printStackTrace();
}
}
});
}
public MainFrame() {
setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
setBounds(100, 100, 450, 300);
contentPane = new JPanel();
contentPane.setBorder(new EmptyBorder(5, 5, 5, 5));
setContentPane(contentPane);
contentPane.setLayout(null);
JTabbedPane tabbedPane = new JTabbedPane(JTabbedPane.TOP);
tabbedPane.setBounds(10, 11, 414, 240);
contentPane.add(tabbedPane);
JPanel panel = new JPanel();
panel.addFocusListener(new FocusListener() {
#Override
public void focusLost(FocusEvent arg0) {
System.out.println("lost");
// I want to do something here, if I reach here!
}
#Override
public void focusGained(FocusEvent arg0) {
System.out.println("gained");
// I want to do something here, if I reach here!
}
});
tabbedPane.addTab("New tab", null, panel, null);
JButton button = new JButton("New button");
panel.add(button);
JPanel panel_1 = new JPanel();
tabbedPane.addTab("New tab", null, panel_1, null);
JPanel panel_2 = new JPanel();
tabbedPane.addTab("New tab", null, panel_2, null);
}
}
I've created this class to test it and then add the onFocusListener in my main code, but it's not working the way I expect. Please tell what's wrong or is this the right EvenetListener at all?

JPanels are not focusable by default. If you ever wanted to use a FocusListener on them, you'd first have to change this property via setFocusable(true).
But even if you do this, a FocusListener is not what you want.
Instead I'd look to listen to the JTabbedPane's model for changes. It uses a SingleSelectionModel, and you can add a ChangeListener to this model, listen for changes, check the component that is currently being displayed and if your component, react.
You are using setBounds and null layouts, something that you will want to avoid doing if you are planning on creating and maintaining anything more than a toy Swing program.
Edit
For example:
import java.awt.BorderLayout;
import java.awt.Component;
import java.awt.Dimension;
import javax.swing.*;
import javax.swing.event.*;
#SuppressWarnings("serial")
public class MainPanel extends JPanel {
private static final int PREF_W = 450;
private static final int PREF_H = 300;
private static final int GAP = 5;
private static final int TAB_COUNT = 5;
private JTabbedPane tabbedPane = new JTabbedPane();
public MainPanel() {
for (int i = 0; i < TAB_COUNT; i++) {
JPanel panel = new JPanel();
panel.add(new JButton("Button " + (i + 1)));
panel.setName("Panel " + (i + 1));
tabbedPane.add(panel.getName(), panel);
}
setBorder(BorderFactory.createEmptyBorder(GAP, GAP, GAP, GAP));
setLayout(new BorderLayout());
add(tabbedPane, BorderLayout.CENTER);
tabbedPane.getModel().addChangeListener(new ChangeListener() {
#Override
public void stateChanged(ChangeEvent evt) {
Component component = tabbedPane.getSelectedComponent();
System.out.println("Component Selected: " + component.getName());
}
});
}
#Override
public Dimension getPreferredSize() {
return new Dimension(PREF_W, PREF_H);
}
private static void createAndShowGui() {
MainPanel mainPanel = new MainPanel();
JFrame frame = new JFrame("MainPanel");
frame.setDefaultCloseOperation(JFrame.EXIT_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();
}
});
}
}

JPanel is a lightweight container and it is not a Actionable component so it does not get focus events. It lets you add focus listener because of swing component hierarchy. In Order to get tab selected events you need to use JTabbedPane#addChangeListener.
Hope this helps.

Related

How can I print a JPanel content in another JPanel?

I'm creating a GUI with two JPanels, one for typing and another to show the same text that I type in the first JPanel. How can I make the second JPanel printable? Is there a way to show in the second JPanel the same text that I type in the first JPanel?
You'll want to have them share the same Document.
textArea2.setDocument(textArea1.getDocument());
public void createAndShowGUI() {
// ... frame, panel etc.
// each panel has BorderLayout
scrollPane1 = new JScrollPane();
panel1.add(scrollPane1, BorderLayout.CENTER);
scrollPane2 = new JScrollPane();
panel2.add(scrollPane2, BorderLayout.CENTER);
textArea1 = new JTextArea();
scrollPane1.setViewportView(textArea1);
textArea1.requestFocus();
textArea2 = new JTextArea();
scrollPane2.setViewportView(textArea2);
textArea2.setEditable(false);
textArea1.getDocument().addDocumentListener(new MyDocumentListener());
textArea2.getDocument().addDocumentListener(new MyDocumentListener());
}
class MyDocumentListener implements DocumentListener {
public void insertUpdate(DocumentEvent e) {
textArea2.setDocument(textArea1.getDocument());
textArea1.setCaretPosition(textArea1.getDocument().getLength());
textArea2.setCaretPosition(textArea2.getDocument().getLength());
}
public void removeUpdate(DocumentEvent e) {
textArea2.setDocument(textArea1.getDocument());
textArea1.setCaretPosition(textArea1.getDocument().getLength());
textArea2.setCaretPosition(textArea2.getDocument().getLength());
}
public void changedUpdate(DocumentEvent e) {
// Plain text components don't fire these events.
}
}
From: The Tutorials and this and this.
EDIT:
Here is the full example of this implementation:
import javax.swing.*;
import java.awt.*;
import javax.swing.text.*;
import javax.swing.event.*;
class DocumentListenerTest {
JFrame frame;
JPanel panel, panel1, panel2;
JScrollPane scrollPane1, scrollPane2;
JTextArea textArea1, textArea2;
JSplitPane splitPane;
public DocumentListenerTest() {
createAndShowGUI();
}
public void createAndShowGUI() {
frame = new JFrame("Copy Text");
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
//frame.setMinimumSize(new Dimension(200, 200));
panel = new JPanel();
panel.setLayout(new BorderLayout(5, 5));
frame.setContentPane(panel);
panel1 = new JPanel();
panel1.setLayout(new BorderLayout());
panel.add(panel1);
panel2 = new JPanel();
panel2.setLayout(new BorderLayout());
panel.add(panel2, BorderLayout.SOUTH);
scrollPane1 = new JScrollPane();
panel1.add(scrollPane1, BorderLayout.CENTER);
scrollPane2 = new JScrollPane();
panel2.add(scrollPane2, BorderLayout.CENTER);
textArea1 = new JTextArea();
scrollPane1.setViewportView(textArea1);
textArea1.requestFocus();
textArea2 = new JTextArea();
scrollPane2.setViewportView(textArea2);
textArea2.setEditable(false);
splitPane = new JSplitPane(JSplitPane.VERTICAL_SPLIT, scrollPane1, scrollPane2);
panel.add(splitPane, BorderLayout.CENTER);
splitPane.setDividerLocation(0.5);
splitPane.setResizeWeight(0.5);
textArea1.getDocument().addDocumentListener(new MyDocumentListener());
textArea2.getDocument().addDocumentListener(new MyDocumentListener());
frame.pack();
frame.setVisible(true);
}
class MyDocumentListener implements DocumentListener {
public void insertUpdate(DocumentEvent e) {
textArea2.setDocument(textArea1.getDocument());
//textArea1.setCaretPosition(textArea1.getDocument().getLength());
//textArea2.setCaretPosition(textArea2.getDocument().getLength());
textArea2.setCaretPosition(textArea1.getCaretPosition());
}
public void removeUpdate(DocumentEvent e) {
textArea2.setDocument(textArea1.getDocument());
//textArea1.setCaretPosition(textArea1.getDocument().getLength());
//textArea2.setCaretPosition(textArea2.getDocument().getLength());
textArea2.setCaretPosition(textArea1.getCaretPosition());
}
public void changedUpdate(DocumentEvent e) {
// Plain text components don't fire these events.
}
}
public static void main(String[] args) {
SwingUtilities.invokeLater(new Runnable() {
public void run() {
new DocumentListenerTest();
}
});
}
}
Here is a sample gif:

Java : Can't display JPanel above a JLabel with image

here's my problem : I display an ArrayList of JLabel with image and a JPanel with buttons inside a JPanel and I want to display my JPanel above my JLabel when I press a button. But when I press the button, my JPanel is under the JLabels.
Please don't tell me to use a JLayerPane cause if I can do without it it would be best.
Thanks for your solutions.
Here's an exemple of my code :
To run this put the image 100x100 found here :
http://www.html5gamedevs.com/topic/32190-image-very-large-when-using-the-dragging-example/
in a file named image
Main :
public class Main {
public static void main(String[] args) {
JFrame frame = new JFrame();
frame.setTitle("test");
frame.setSize(900,700);
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.setResizable(false);
frame.setLocationRelativeTo(null);
JPanelControler ctrl = new JPanelControler();
frame.add(ctrl.getMyJpanel());
frame.setVisible(true);
}
}
MyJPanelControler :
public class JPanelControler {
private MyJPanel myJpanel;
public JPanelControler() {
myJpanel = new MyJPanel();
myJpanel.createJLabel();
myJpanel.getButton().addActionListener(new ActionListener() {
#Override
public void actionPerformed(ActionEvent e) {
myJpanel.displayJPanel();
}
});
}
public MyJPanel getMyJpanel() {
return myJpanel;
}
}
MyJPanel :
public class MyJPanel extends JPanel {
private JButton button;
private ArrayList<JLabel> labels;
//a JPanel that contains buttons,... I won't put this class here
private JPanel panel;
public MyJPanel() {
setLayout(null);
button = new JButton("X");
button.setBounds(600,600,50,50);
add(button);
}
public void createJLabel() {
labels = new ArrayList<>();
JLabel label;
try {
BufferedImage image = ImageIO.read(new File("images/image.jpg"));
for(int i=0; i<2; i++) {
label = new JLabel(new ImageIcon(image));
label.setBounds(i*100,50,image.getWidth(), image.getHeight());
labels.add(label);
add(label);
}
} catch (IOException e) {
e.printStackTrace();
}
}
public void displayJPanel() {
panel = new JPanel();
panel.setLayout(null);
JButton b = new JButton("Ok");
b.setBounds(0,0,100, 50);
JButton b2 = new JButton("Cancel");
b2.setBounds(0,50,100, 50);
panel.setBounds(150,50, 100, 100);
panel.add(b);
panel.add(b2);
add(panel);
refresh();
}
public void refresh() {
invalidate();
revalidate();
repaint();
}
public JButton getButton() {return this.button; }
}
If you want the buttons to appear over plain images, then you have one of two options:
Draw the images in a paintComponent override in the main JPanel and not as ImageIcons within a JLabel. This will allow you to add components to this same JPanel, including buttons and such, and the images will remain in the background. If you go this route, be sure to call the super.paintComponent(g); method first thing in your override.
Or you could use a JLayeredPane (regardless of your not wanting to do this). You would simply put the background JPanel into the JLayeredPane.DEFAULT_LAYER, the bottom layer (constant is Integer 0), and place the newly displayed JButton Panel in the JLayeredPane.PALETTE_LAYER, which us just above the default. If you go this route, be sure that the added JPanel is not opaque, else it will cover over all images completely.
For an example of the 2nd suggestion, please see below:
import java.awt.event.*;
import java.awt.image.BufferedImage;
import java.io.IOException;
import java.net.URL;
import java.util.ArrayList;
import javax.imageio.ImageIO;
import javax.swing.*;
public class JPanelControler {
private MyJPanel myJpanel;
public JPanelControler() {
myJpanel = new MyJPanel();
myJpanel.createJLabel();
myJpanel.getButton().addActionListener(new ActionListener() {
#Override
public void actionPerformed(ActionEvent e) {
myJpanel.displayJPanel();
}
});
}
public MyJPanel getMyJpanel() {
return myJpanel;
}
public static void main(String[] args) {
JFrame frame = new JFrame();
frame.setTitle("test");
frame.setSize(900, 700);
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.setResizable(false);
frame.setLocationRelativeTo(null);
JPanelControler ctrl = new JPanelControler();
frame.add(ctrl.getMyJpanel());
frame.setVisible(true);
}
}
class MyJPanel extends JLayeredPane {
private static final String IMG_PATH = "https://upload.wikimedia.org/wikipedia"
+ "/commons/thumb/f/fc/Gros_Perr%C3%A9.jpg/100px-Gros_Perr%C3%A9.jpg";
private JButton button;
private ArrayList<JLabel> labels;
// a JPanel that contains buttons,... I won't put this class here
private JPanel panel;
public MyJPanel() {
setLayout(null);
button = new JButton("X");
button.setBounds(600, 600, 50, 50);
add(button, JLayeredPane.DEFAULT_LAYER); // add to the bottom
}
public void createJLabel() {
labels = new ArrayList<>();
JLabel label;
try {
URL imgUrl = new URL(IMG_PATH); // ** added to make program work for all
BufferedImage image = ImageIO.read(imgUrl);
for (int i = 0; i < 2; i++) {
label = new JLabel(new ImageIcon(image));
label.setBounds(i * 100, 50, image.getWidth(), image.getHeight());
labels.add(label);
add(label);
}
} catch (IOException e) {
e.printStackTrace();
}
}
public void displayJPanel() {
panel = new JPanel();
panel.setLayout(null);
panel.setOpaque(false); // ** make sure can see through
JButton b = new JButton("Ok");
b.setBounds(0, 0, 100, 50);
JButton b2 = new JButton("Cancel");
b2.setBounds(0, 50, 100, 50);
panel.setBounds(150, 50, 100, 100);
panel.add(b);
panel.add(b2);
add(panel, JLayeredPane.PALETTE_LAYER); // add it above the default layer
refresh();
}
public void refresh() {
// invalidate(); // not needed
revalidate();
repaint();
}
public JButton getButton() {
return this.button;
}
}

How do I change JFrame size from the minimum window size?

I am trying to learn how to use CardLayout instead of multiple JFrames and I am messing around with this code I found on youtube. I tried calling setSize() on all the JPanes but it does not change the size and it remains at the minimum window size. Is the reason I can't set the size because of this line of code: "panelCont.setLayout(cl);" ?
import javax.swing.*;
import java.awt.*;
import java.awt.event.*;
public class CLayout {
JFrame frame = new JFrame("CardLayout");
JPanel panelCont = new JPanel();
JPanel panelFirst = new JPanel();
JPanel panelSecond = new JPanel();
JButton buttonOne = new JButton("Switch to second panel");
JButton buttonSecond = new JButton("Switch to first panel");
CardLayout cl = new CardLayout();
public CLayout() {
panelCont.setLayout(cl);
panelFirst.add(buttonOne);
panelSecond.add(buttonSecond);
panelFirst.setBackground(Color.BLUE);
panelSecond.setBackground(Color.GREEN);
panelCont.add(panelFirst, "1");
panelCont.add(panelSecond, "2");
cl.show(panelCont, "1");
buttonOne.addActionListener(new ActionListener() {
#Override
public void actionPerformed(ActionEvent e) {
cl.show(panelCont, "2");
}
});
buttonSecond.addActionListener(new ActionListener() {
#Override
public void actionPerformed(ActionEvent e) {
cl.show(panelCont, "1");
}
});
frame.add(panelCont);
frame.setDefaultCloseOperation(JFrame.DISPOSE_ON_CLOSE);
frame.pack();
frame.setVisible(true);
}
public static void main(String[] args) {
SwingUtilities.invokeLater(new Runnable() {
#Override
public void run() {
new CLayout();
}
});
}
}
Yes, it's for CardLayout but also it's possible to do resize. You can nest your JPanels for instance. or use something like this :
Code
import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
import javax.swing.border.Border;
public class MultiSizedPanels {
private static void createAndShowUI() {
final CardLayout cardLayout = new CardLayout();
final JPanel cardHolder = new JPanel(cardLayout);
JLabel[] labels = {
new JLabel("Small Label", SwingConstants.CENTER),
new JLabel("Medium Label", SwingConstants.CENTER),
new JLabel("Large Label", SwingConstants.CENTER)};
for (int i = 0; i < labels.length; i++) {
int padding = 50;
Dimension size = labels[i].getPreferredSize();
size = new Dimension(size.width + 2 * (i + 1) * padding, size.height + 2 * (i + 1) * padding);
labels[i].setPreferredSize(size);
Border lineBorder = BorderFactory.createLineBorder(Color.blue);
labels[i].setBorder(lineBorder);
JPanel containerPanel = new JPanel(new GridBagLayout());
containerPanel.add(labels[i]);
cardHolder.add(containerPanel, String.valueOf(i));
}
JButton nextButton = new JButton("Next");
nextButton.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent e) {
cardLayout.next(cardHolder);
}
});
JPanel btnHolder = new JPanel();
btnHolder.add(nextButton);
JFrame frame = new JFrame("MultiSizedPanels");
frame.getContentPane().add(cardHolder, BorderLayout.CENTER);
frame.getContentPane().add(btnHolder, BorderLayout.SOUTH);
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.pack();
frame.setLocationRelativeTo(null);
frame.setVisible(true);
}
public static void main(String[] args) {
java.awt.EventQueue.invokeLater(new Runnable() {
public void run() {
createAndShowUI();
}
});
}
}
Where component (here a JLabel rather than a JPanel) has it's preferredSize set, then place it in another JPanel.
I hope this helps you.

Adding JPanels from other classes to the cardLayout

I've got 3 windows in 3 separate classes and I would like to use cardLayout so that when you click the next button, the next window will appear. How do I add JPanels containing different elements to one cardLayout? This is the first window: (the only difference is the background though - but it represents the idea of how I got it actually)
public class Window1 extends JPanel implements ActionListener {
static CardLayout cardLayout = new CardLayout();
public Window1() {
init();
}
private void init() {
JPanel jp = new JPanel(new BorderLayout());
JPanel jp2 = new Window2();
//JPanel jp3 = new Window3();
JLabel textLabel = new JLabel("Window1");
jp.setBackground(Color.GREEN);
jp.add(textLabel, BorderLayout.CENTER);
JButton nextButton = new JButton("NEXT");
nextButton.setActionCommand("next");
nextButton.addActionListener(this);
jp.add(nextButton, BorderLayout.EAST);
setLayout(cardLayout);
add(jp, "string");
add(jp2, "string");
//add(jp3, "string");
}
public void actionPerformed(ActionEvent e) {
if (e.getActionCommand().equalsIgnoreCase("next")) {
// go to the next window
cardLayout.next(this);
}
}
private static void createAndShowGUI() {
JFrame frame = new JFrame("test");
frame.getContentPane().setLayout(Window1.cardLayout);
frame.getContentPane().add(new Window1(), "Center");
frame.getContentPane().add(new Window2(), "Center");
frame.getContentPane().add(new Window3(), "Center");
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.setSize(550, 450);
frame.setVisible(true);
}
public static void main(String[] args) {
java.awt.EventQueue.invokeLater(new Runnable() {
public void run() {
createAndShowGUI();
}
});
}
}
The second window:
public class Window2 extends JPanel implements ActionListener {
//static CardLayout cardLayout = new CardLayout();
public Window2() {
init();
}
private void init() {
setLayout(new BorderLayout());
JLabel textLabel = new JLabel("Window2");
setBackground(Color.RED);
add(textLabel, BorderLayout.CENTER);
JButton nextButton = new JButton("NEXT");
nextButton.setActionCommand("next");
nextButton.addActionListener(this);
add(nextButton, BorderLayout.EAST);
//setLayout(cardLayout);
//JPanel jp3 = new Window3();
//add(jp3, "string");
}
public void actionPerformed(ActionEvent e) {
if (e.getActionCommand().equalsIgnoreCase("next")) {
// go to the next window??
System.out.println("window2");
Window1.cardLayout.next(this);
}
}
}
And the last one:
public class Window3 extends JPanel implements ActionListener {
public Window3() {
init();
}
private void init() {
setLayout(new BorderLayout());
JLabel textLabel = new JLabel("Window3");
setBackground(Color.BLUE);
add(textLabel, BorderLayout.CENTER);
JButton nextButton = new JButton("NEXT");
nextButton.setActionCommand("next");
nextButton.addActionListener(this);
add(nextButton, BorderLayout.EAST);
}
public void actionPerformed(ActionEvent e) {
if (e.getActionCommand().equalsIgnoreCase("next")) {
// go to the next window
// Window1.cardLayout.next(this);
}
}
}
I had made a small program, hopefully the comments written in the program, might be able to guide you, to understand how to use CardLayout.
import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
/* Here we are first declaring our class that will act as the
* base for other panels or in other terms the base for CardLayout.
*/
public class CardLayoutTest
{
private static final String CARD_JBUTTON = "Card JButton";
private static final String CARD_JTEXTFIELD = "Card JTextField";
private static final String CARD_JRADIOBUTTON = "Card JRadioButton";
private static void createAndShowGUI()
{
JFrame frame = new JFrame("Card Layout Test");
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.setLocationRelativeTo(null);
// This JPanel is the base for CardLayout for other JPanels.
final JPanel contentPane = new JPanel();
contentPane.setLayout(new CardLayout(20, 20));
/* Here we be making objects of the Window Series classes
* so that, each one of them can be added to the JPanel
* having CardLayout.
*/
Window1 win1 = new Window1();
contentPane.add(win1, CARD_JBUTTON);
Window2 win2 = new Window2();
contentPane.add(win2, CARD_JTEXTFIELD);
Window3 win3 = new Window3();
contentPane.add(win3, CARD_JRADIOBUTTON);
/* We need two JButtons to go to the next Card
* or come back to the previous Card, as and when
* desired by the User.
*/
JPanel buttonPanel = new JPanel();
final JButton previousButton = new JButton("PREVIOUS");
previousButton.setBackground(Color.BLACK);
previousButton.setForeground(Color.WHITE);
final JButton nextButton = new JButton("NEXT");
nextButton.setBackground(Color.RED);
nextButton.setForeground(Color.WHITE);
buttonPanel.add(previousButton);
buttonPanel.add(nextButton);
/* Adding the ActionListeners to the JButton,
* so that the user can see the next Card or
* come back to the previous Card, as desired.
*/
previousButton.addActionListener(new ActionListener()
{
public void actionPerformed(ActionEvent ae)
{
CardLayout cardLayout = (CardLayout) contentPane.getLayout();
cardLayout.previous(contentPane);
}
});
nextButton.addActionListener(new ActionListener()
{
public void actionPerformed(ActionEvent ae)
{
CardLayout cardLayout = (CardLayout) contentPane.getLayout();
cardLayout.next(contentPane);
}
});
// Adding the contentPane (JPanel) and buttonPanel to JFrame.
frame.add(contentPane, BorderLayout.CENTER);
frame.add(buttonPanel, BorderLayout.PAGE_END);
frame.pack();
frame.setVisible(true);
}
public static void main(String... args)
{
SwingUtilities.invokeLater(new Runnable()
{
public void run()
{
createAndShowGUI();
}
});
}
}
class Window1 extends JPanel
{
/*
* Here this is our first Card of CardLayout, which will
* be added to the contentPane object of JPanel, which
* has the LayoutManager set to CardLayout.
* This card consists of Two JButtons.
*/
private ActionListener action;
public Window1()
{
init();
}
private void init()
{
final JButton clickButton = new JButton("CLICK ME");
final JButton dontClickButton = new JButton("DON\'T CLICK ME");
action = new ActionListener()
{
public void actionPerformed(ActionEvent ae)
{
if (ae.getSource() == clickButton)
{
JOptionPane.showMessageDialog(null, "Hello there dude!"
, "Right Button", JOptionPane.INFORMATION_MESSAGE);
}
else if (ae.getSource() == dontClickButton)
{
JOptionPane.showMessageDialog(null, "I told you not to click me!"
, "Wrong Button", JOptionPane.PLAIN_MESSAGE);
}
}
};
clickButton.addActionListener(action);
dontClickButton.addActionListener(action);
add(clickButton);
add(dontClickButton);
}
}
class Window2 extends JPanel implements ActionListener
{
/*
* Here this is our second Card of CardLayout, which will
* be added to the contentPane object of JPanel, which
* has the LayoutManager set to CardLayout.
* This card consists of a JLabel and a JTextField
* with GridLayout.
*/
private JTextField textField;
public Window2()
{
init();
}
private void init()
{
setLayout(new GridLayout(1, 2));
JLabel userLabel = new JLabel("Your Name : ");
textField = new JTextField();
textField.addActionListener(this);
add(userLabel);
add(textField);
}
public void actionPerformed(ActionEvent e)
{
if (textField.getDocument().getLength() > 0)
JOptionPane.showMessageDialog(null, "Your Name is : " + textField.getText()
, "User\'s Name : ", JOptionPane.QUESTION_MESSAGE);
}
}
class Window3 extends JPanel
{
/*
* Here this is our third Card of CardLayout, which will
* be added to the contentPane object of JPanel, which
* has the LayoutManager set to CardLayout.
* This card consists of Two JLabels and two JCheckBox
* with GridLayout.
*/
private ActionListener state;
public Window3()
{
init();
}
public void init()
{
setLayout(new GridLayout(2, 2));
JLabel maleLabel = new JLabel("MALE", JLabel.CENTER);
final JCheckBox maleBox = new JCheckBox();
JLabel femaleLabel = new JLabel("FEMALE", JLabel.CENTER);
final JCheckBox femaleBox = new JCheckBox();
state = new ActionListener()
{
public void actionPerformed(ActionEvent ae)
{
if (maleBox == (JCheckBox) ae.getSource())
{
femaleBox.setSelected(false);
JOptionPane.showMessageDialog(null, "Congrats you are a Male"
, "Gender : ", JOptionPane.INFORMATION_MESSAGE);
}
else if (femaleBox == (JCheckBox) ae.getSource())
{
maleBox.setSelected(false);
JOptionPane.showMessageDialog(null, "Congrats you are a Female"
, "Gender : ", JOptionPane.INFORMATION_MESSAGE);
}
}
};
maleBox.addActionListener(state);
femaleBox.addActionListener(state);
add(maleLabel);
add(maleBox);
add(femaleLabel);
add(femaleBox);
}
}
There are a couple things:
As your program can only run 1 main method, each class doesnt need one, but whichever you do run should create an instance of each panel you want to add to your CardLayout.
You also do not seem to add your Windows to your CardLayout at all. You could try the following (uncomplied). This would only be needed in one class:
private static void createAndShowGUI() {
JFrame frame = new JFrame("test");
frame.getContentPane().setLayout(Window1.cardLayout);
frame.getContentPane().add(new Window1());
frame.getContentPane().add(new Window2());
frame.getContentPane().add(new Window3());
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.setSize(550, 450);
frame.setVisible(true);
}
Further (and this might just be due to the simplicity of your example), I would just have 1 class, and it would take the name of the panel and the color of the background to the constructor. These could be passed into your init() method and your design would be somewhat streamlined.

JRadioButton Will not appear until Mouse over

import java.awt.Frame;
import java.awt.event.ItemEvent;
import java.awt.event.ItemListener;
import javax.swing.*;
public class IndicatorWindow implements ItemListener {
JRadioButton RMA, EMA, SMA, Williams, Stochastic;
JPanel IndPan, RadioPanel, title;
JLabel Lab;
JButton OK;
public JPanel createContentPane() {
JPanel GUI = new JPanel();
GUI.setLayout(null);
title = new JPanel();
title.setLayout(null);
title.setLocation(0, 0);
title.setSize(500, 145);
GUI.add(title);
Lab = new JLabel("Please Select Indicator Type");
Lab.setLocation(5, 0);
Lab.setSize(200, 30);
title.add(Lab);
ButtonGroup bg1 = new ButtonGroup();
RadioPanel = new JPanel();
RadioPanel.setLayout(null);
RadioPanel.setLocation(10, 30);
RadioPanel.setSize(190, 220);
GUI.add(RadioPanel);
RMA = new JRadioButton("RMA");
RMA.setLocation(0, 0);
RMA.addItemListener(this);
RMA.setSize(110, 20);
bg1.add(RMA);
RadioPanel.add(RMA);
EMA = new JRadioButton("EMA");
EMA.setLocation(0, 30);
EMA.addItemListener(this);
EMA.setSize(110, 20);
bg1.add(EMA);
RadioPanel.add(EMA);
SMA = new JRadioButton("SMA");
SMA.setLocation(0, 60);
SMA.addItemListener(this);
SMA.setSize(110, 20);
bg1.add(SMA);
RadioPanel.add(SMA);
Stochastic = new JRadioButton("Stochastic");
Stochastic.setLocation(0, 90);
Stochastic.addItemListener(this);
Stochastic.setSize(110, 20);
bg1.add(Stochastic);
RadioPanel.add(Stochastic);
Williams = new JRadioButton("Williams");
Williams.setLocation(0, 120);
Williams.addItemListener(this);
Williams.setSize(110, 20);
bg1.add(Williams);
RadioPanel.add(Williams);
OK = new JButton();
OK.setText("Confirm");
OK.setLocation(45, 150);
OK.addItemListener(this);
OK.setSize(90, 30);
RadioPanel.add(OK);
//GUI.setOpaque(true);
return GUI;
}
public void itemStateChanged(ItemEvent e) {
Object source = e.getItemSelectable();
if (source == RMA) {
System.out.print("Browse");
} else if (source == EMA) {
System.out.print("EMA");
} else if (source == SMA) {
System.out.print("SMA");
} else if (source == Williams) {
System.out.print("Williams");
} else if (source == Stochastic) {
System.out.print("Stochastic");
}
}
private static void createAndShowGUI() {
JFrame frame = new JFrame("Indicators");
IndicatorWindow ind = new IndicatorWindow();
frame.setContentPane(ind.createContentPane());
frame.setDefaultCloseOperation(JFrame.DISPOSE_ON_CLOSE);
frame.setSize(200, 250);
frame.setLayout(null);
frame.setResizable(true);
frame.setLocationRelativeTo(null);
frame.setVisible(true);
frame.setAlwaysOnTop(true);
frame.setState(Frame.NORMAL);
}
public static void main(String[] args) {
SwingUtilities.invokeLater(new Runnable() {
public void run() {
createAndShowGUI();
}
});
}
}
My problem is that when i compile and run this code, the jFrame appears but there is only one problem, 3 JRadioButtons dont appear until you put your mouse over them. The RMA and Williams radiobuttons appear, the 3 in the middle do not though, any thoughts on why this is?
http://i.stack.imgur.com/gNnIb.jpg
You should be using layout managers. People think using a "null layout" is easier, but it is not and you are more prone to having errors with your code. Layout managers will position and size components properly to make sure all components are displayed. Sometimes you even use multiple different layout managers to achieve the layout you desire.
Your problem in this case is that you have two components occupying the same space in your container. So one component gets painted over top of the other. After you mouse over your radio button, the button is repainted because of the rollover effect of the button. However, now try resizing the frame and the radio buttons will disappear because all the components are repainted and the component is painted over top of the buttons again.
The following line of code is the problem:
// title.setSize(500, 145);
title.setSize(500, 20);
But the real solution is to rewrite the code and use layout managers. While you are at it use proper Java naming conventions. Variable names do NOT start with an uppercase letter. You got "title" and "bg1" correct. So fix "EMA", "RMA" etc...
#camickr is correct. Note how using layout managers (and a little re-factoring) can actually simplify your code. Also, the relevant tutorial suggests using an action listener, rather than an item listener.
import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
/** #see http://stackoverflow.com/questions/5255337 */
public class IndicatorWindow implements ActionListener {
JPanel radioPanel = new JPanel(new GridLayout(0, 1));
JRadioButton rma, ema, sma, stochastic, williams;
ButtonGroup bg = new ButtonGroup();
public JPanel createContentPane() {
JPanel gui = new JPanel(new BorderLayout());
JPanel title = new JPanel();
JLabel lab = new JLabel("Please Select Indicator Type");
title.add(lab);
gui.add(title, BorderLayout.NORTH);
createRadioButton(rma, "RMA");
createRadioButton(ema, "EMA");
createRadioButton(sma, "SMA");
createRadioButton(stochastic, "Stochastic");
createRadioButton(williams, "Williams");
gui.add(radioPanel, BorderLayout.CENTER);
JButton ok = new JButton();
ok.setText("Confirm");
ok.addActionListener(this);
radioPanel.add(ok);
return gui;
}
private void createRadioButton(JRadioButton jrb, String name) {
jrb = new JRadioButton(name);
bg.add(jrb);
jrb.addActionListener(this);
radioPanel.add(jrb);
}
#Override
public void actionPerformed(ActionEvent e) {
System.out.println(e.getActionCommand());
}
private static void createAndShowGUI() {
JFrame frame = new JFrame("Indicators");
frame.add(new IndicatorWindow().createContentPane());
frame.setDefaultCloseOperation(JFrame.DISPOSE_ON_CLOSE);
frame.setAlwaysOnTop(true);
frame.pack();
frame.setLocationRelativeTo(null);
frame.setVisible(true);
}
public static void main(String[] args) {
SwingUtilities.invokeLater(new Runnable() {
#Override
public void run() {
createAndShowGUI();
}
});
}
}
You should add your JRadioButtons with a method:
private void bgAdd (String name, int y)
{
JRadioButton rb = new JRadioButton (name);
rb.setLocation (0, y);
rb.addItemListener (this);
rb.setSize (110, 19);
bg1.add (rb);
radioPanel.add (rb);
}
Calling code:
bgAdd ("RMA", 0);
bgAdd ("EMA", 30);
bgAdd ("SMA", 60);
bgAdd ("Stochastic", 90);
bgAdd ("Williams", 120);
Action:
public void itemStateChanged (ItemEvent e) {
Object button = e.getItemSelectable ();
String source = ((JRadioButton) button).getText ();
System.out.print (source + " ");
}
Then add BoxLayout to the page, for example.

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