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How can I resize my JTextFields in my Jpanel

being new to programming, i'm having a slight issue resizing the text fields I've added to the JPanel. While I could go the route of creating individual panels with their own text field, I though it would be better to add all the components into one panel. Part of my overall idea is to have my add button reference the panel, containing the text fields, to add more text fields on the tracker for users to fill out, and while I can get the fields to display when I implement the setBounds method on my panel object, i'm having tough time figuring out how resize them in the panel itself. And if you have any other advice on my overall structure, I welcome it.
import java.awt.BorderLayout;
import java.awt.Button;
import java.awt.Color;
import java.awt.EventQueue;
import java.awt.Font;
import java.awt.Label;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import javax.swing.JButton;
import javax.swing.JEditorPane;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JPanel;
import javax.swing.JTextField;
public class UI {
JFrame frame;
JLabel Title,Name, CheckOut, CheckIn, Email;
JTextField NameField,CheckOutField, CheckInField, EmailField;
JButton Add, Delete;
JPanel buttons, textfields, primary;
public static void main(String[] args) {
EventQueue.invokeLater(new Runnable() {
public void run() {
try {
UI window = new UI();
window.frame.setVisible(true);
} catch (Exception e) {
e.printStackTrace();
}
}
});
}
public UI(){
design();
}
private void design(){
frame = new JFrame("Form 48 Tracker");
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.setBounds(100, 100, 750, 400);
frame.getContentPane().setLayout(null);
Title = new JLabel();
Title.setText("Form 48 Tracker");
Title.setFont(new Font("Calibri", Font.PLAIN, 28));
Title.setBounds(233, 11, 200, 75);
frame.getContentPane().add(Title);
Title.setForeground(Color.BLACK);
Name = new JLabel();
Name.setText("Name");
Name.setFont(new Font("Calibri", Font.PLAIN, 15));
Name.setBounds(50, 80, 128, 20);
frame.getContentPane().add(Name);
Name.setForeground(Color.BLACK);
CheckOut = new JLabel();
CheckOut.setText("Check Out Date");
CheckOut.setFont(new Font("Calibri", Font.PLAIN, 15));
CheckOut.setBounds(200, 80, 128, 20);
frame.getContentPane().add(CheckOut);
CheckOut.setForeground(Color.BLACK);
CheckIn = new JLabel();
CheckIn.setText("Check In Date");
CheckIn.setFont(new Font("Calibri", Font.PLAIN, 15));
CheckIn.setBounds(350, 80, 128, 20);
frame.getContentPane().add(CheckIn);
CheckIn.setForeground(Color.BLACK);
Email = new JLabel();
Email.setText("Email");
Email.setFont(new Font("Calibri", Font.PLAIN, 15));
Email.setBounds(500, 80, 128, 20);
frame.getContentPane().add(Email);
Email.setForeground(Color.BLACK);
Add = new JButton("Add");
buttons = new JPanel();
buttons.add(Add);
buttons.setBounds(200, 270, 157, 50); //x , y , width , height//
frame.getContentPane().add(buttons);
Add.addActionListener(new ActionListener(){
public void actionPerformed(ActionEvent e){
}
});
Delete = new JButton("Delete");
buttons = new JPanel();
buttons.add(Delete);
buttons.setBounds(605, 101, 128, 50);
frame.getContentPane().add(buttons);
primary = new JPanel();
NameField = new JTextField();
CheckOutField = new JTextField();
CheckInField = new JTextField();
EmailField = new JTextField();
primary.add(NameField);
primary.add(CheckOutField);
primary.add(CheckInField);
primary.add(EmailField);
primary.setBounds(50, 110, 128, 20);
frame.getContentPane().add(primary);
}
}

Let's concentrate on the code that's causing the problem, and only that code. I've created a minimal example program, one that has enough code to compile and run, and that demonstrates the problem, but that has no unnecessary code:
import javax.swing.*;
public class UiFoo {
public static void main(String[] args) {
SwingUtilities.invokeLater(() -> {
JFrame frame = new JFrame("Foo");
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.setLayout(null); // **** no!! ****
JPanel primary = new JPanel();
JTextField NameField = new JTextField();
JTextField CheckOutField = new JTextField();
JTextField CheckInField = new JTextField();
JTextField EmailField = new JTextField();
primary.add(NameField);
primary.add(CheckOutField);
primary.add(CheckInField);
primary.add(EmailField);
primary.setBounds(50, 110, 128, 20);
frame.getContentPane().add(primary);
frame.setSize(600, 250);
frame.setLocationRelativeTo(null);
frame.setVisible(true);
});
}
}
So, if you run this code, you'll see 4 very small JTextFields. Why are they so small? Because you've not set the columns property for the JTextFields, and so they default to columns size 0 and show up like so:
So it's better if you can give the JTextField a columns property so that they have some width, e.g., make this change:
JPanel primary = new JPanel();
int columns = 8;
JTextField NameField = new JTextField(columns);
JTextField CheckOutField = new JTextField(columns);
JTextField CheckInField = new JTextField(columns);
JTextField EmailField = new JTextField();
But this just shows one JTextField, and cuts off the bottom as well:
Why? Because you're artificially constraining the size of the containing JPanel, primary via:
primary.setBounds(50, 110, 128, 20);
This containing JPanel is only 128 pixels wide by 20 pixels high, meaning that it won't even display one JTextField well.
One solution is to use a mix of layout managers and JPanels as well as a JScrollPane to allow for a grid of JPanels to be added, something like so (try it out!):
import java.awt.BorderLayout;
import java.awt.Dimension;
import java.awt.GridLayout;
import javax.swing.*;
#SuppressWarnings("serial")
public class UiFoo2 extends JPanel {
JPanel singleColumnPanel = new JPanel(new GridLayout(0, 1, 2, 2));
public UiFoo2() {
JButton addButton = new JButton("Add");
addButton.addActionListener(e -> {
JPanel rowPanel = new JPanel(new GridLayout(1, 4, 2, 2));
for (int i = 0; i < 4; i++) {
rowPanel.add(new JTextField(8));
}
singleColumnPanel.add(rowPanel);
singleColumnPanel.revalidate();
singleColumnPanel.repaint();
});
JPanel buttonPanel = new JPanel();
buttonPanel.add(addButton);
JPanel labelPanel = new JPanel(new GridLayout(1, 4, 2, 2));
labelPanel.add(new JLabel("Name", SwingConstants.CENTER));
labelPanel.add(new JLabel("Check Out Date", SwingConstants.CENTER));
labelPanel.add(new JLabel("Check In Date", SwingConstants.CENTER));
labelPanel.add(new JLabel("Email", SwingConstants.CENTER));
singleColumnPanel.add(labelPanel);
JPanel containerPanel = new JPanel(new BorderLayout(5, 5));
containerPanel.add(singleColumnPanel, BorderLayout.PAGE_START);
JScrollPane scrollPane = new JScrollPane(containerPanel);
scrollPane.setVerticalScrollBarPolicy(JScrollPane.VERTICAL_SCROLLBAR_ALWAYS);
setBorder(BorderFactory.createEmptyBorder(5, 5, 5, 5));
setPreferredSize(new Dimension(650, 400));
setLayout(new BorderLayout());
add(scrollPane, BorderLayout.CENTER);
add(buttonPanel, BorderLayout.PAGE_END);
}
private static void createAndShowGui() {
UiFoo2 mainPanel = new UiFoo2();
JFrame frame = new JFrame("UiFoo2");
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.getContentPane().add(mainPanel);
frame.pack();
frame.setLocationRelativeTo(null);
frame.setVisible(true);
}
public static void main(String[] args) {
SwingUtilities.invokeLater(() -> createAndShowGui());
}
}
This will create a row JPanel that holds four JTextFields that get added to the JScrollPane when the add JButton is pressed, and looks like so:
but we still can do better. Why not instead create a class to hold a row of data, something like so:
import java.util.Date;
public class Form48Customer {
private String name;
private Date checkIn;
private Date checkOut;
private String Email;
public Form48Customer(String name, Date checkIn, Date checkOut, String email) {
this.name = name;
this.checkIn = checkIn;
this.checkOut = checkOut;
Email = email;
}
public Date getCheckIn() {
return checkIn;
}
public void setCheckIn(Date checkIn) {
this.checkIn = checkIn;
}
public Date getCheckOut() {
return checkOut;
}
public void setCheckOut(Date checkOut) {
this.checkOut = checkOut;
}
public String getName() {
return name;
}
public String getEmail() {
return Email;
}
// should override hashCode and equals here
}
and then create a JTable complete with custom model to display objects of this type, and then display them in the GUI. This is much cleaner, more flexible, and extendable. Something like so:
import java.awt.*;
import java.awt.event.*;
import java.beans.PropertyChangeEvent;
import java.beans.PropertyChangeListener;
import java.text.*;
import java.util.Date;
import javax.swing.*;
import javax.swing.JFormattedTextField.AbstractFormatter;
import javax.swing.table.*;
#SuppressWarnings("serial")
public class Form48TrackerPanel extends JPanel {
public static final String TITLE = "Form 48 Tracker";
private static final String DATE_FORMAT_TXT = "MM/dd/yyyy";
private Form48TableModel model = new Form48TableModel();
private JTable table = new JTable(model);
private JButton addButton = new JButton("Add");
private JButton deleteButton = new JButton("Delete");
private JButton exitButton = new JButton("Exit");
public Form48TrackerPanel() {
final SimpleDateFormat dateFormat = new SimpleDateFormat(DATE_FORMAT_TXT);
TableCellRenderer dateRenderer = new DefaultTableCellRenderer() {
#Override
public Component getTableCellRendererComponent(JTable table, Object value,
boolean isSelected, boolean hasFocus, int row, int column) {
if( value instanceof Date) {
value = dateFormat.format(value);
}
return super.getTableCellRendererComponent(table, value, isSelected, hasFocus, row, column);
}
};
table.getColumnModel().getColumn(1).setCellRenderer(dateRenderer);
table.getColumnModel().getColumn(2).setCellRenderer(dateRenderer);
JLabel titleLabel = new JLabel(TITLE, SwingConstants.CENTER);
titleLabel.setFont(titleLabel.getFont().deriveFont(Font.BOLD, 28f));
addButton.addActionListener(new AddListener());
addButton.setMnemonic(KeyEvent.VK_A);
deleteButton.addActionListener(new DeleteListener());
deleteButton.setMnemonic(KeyEvent.VK_D);
exitButton.addActionListener(new ExitListener());
exitButton.setMnemonic(KeyEvent.VK_X);
JPanel buttonPanel = new JPanel(new GridLayout(1, 0, 5, 0));
buttonPanel.add(addButton);
buttonPanel.add(deleteButton);
buttonPanel.add(exitButton);
setPreferredSize(new Dimension(800, 500));
int ebGap = 8;
setBorder(BorderFactory.createEmptyBorder(ebGap, ebGap, ebGap, ebGap));
setLayout(new BorderLayout(ebGap, ebGap));
add(titleLabel, BorderLayout.PAGE_START);
add(new JScrollPane(table), BorderLayout.CENTER);
add(buttonPanel, BorderLayout.PAGE_END);
model.addRow(new Form48Customer("John Smith", new Date(), new Date(), "JSmith#Yahoo.com"));
model.addRow(new Form48Customer("Fred Flinstone", new Date(), new Date(), "FFlinstone#GMail.com"));
}
private class AddListener implements ActionListener {
#Override
public void actionPerformed(ActionEvent e) {
AddForm48Panel addFormPanel = new AddForm48Panel();
int result = JOptionPane.showConfirmDialog(Form48TrackerPanel.this,
addFormPanel, "Add Customer", JOptionPane.OK_CANCEL_OPTION,
JOptionPane.PLAIN_MESSAGE);
if (result == JOptionPane.OK_OPTION) {
Form48Customer customer = addFormPanel.getForm48Customer();
model.addRow(customer);
}
}
}
private class DeleteListener implements ActionListener {
#Override
public void actionPerformed(ActionEvent e) {
// TODO *** finish this code ***
}
}
private class ExitListener implements ActionListener {
#Override
public void actionPerformed(ActionEvent e) {
Window win = SwingUtilities.getWindowAncestor(Form48TrackerPanel.this);
win.dispose();
}
}
private static void createAndShowGui() {
Form48TrackerPanel mainPanel = new Form48TrackerPanel();
JFrame frame = new JFrame(TITLE);
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.getContentPane().add(mainPanel);
frame.pack();
frame.setLocationRelativeTo(null);
frame.setVisible(true);
}
public static void main(String[] args) {
SwingUtilities.invokeLater(() -> createAndShowGui());
}
}
#SuppressWarnings("serial")
class AddForm48Panel extends JPanel {
private static final int TFIELD_COLS = 10;
private static final String DATE_FORMAT_TXT = "MM/dd/yyyy";
private static final Format DATE_FORMAT = new SimpleDateFormat(DATE_FORMAT_TXT);
private static final Insets INSETS = new Insets(5, 5, 5, 5);
private JTextField nameField = new JTextField(TFIELD_COLS);
private JFormattedTextField checkOutDateField = new JFormattedTextField(DATE_FORMAT);
private JFormattedTextField checkInDateField = new JFormattedTextField(DATE_FORMAT);
private JTextField emailField = new JTextField(TFIELD_COLS);
private JComponent[] fields = {nameField, checkOutDateField, checkInDateField, emailField};
private String[] labels = {"Name", "Check Out Date", "Check In Date", "Email"};
public AddForm48Panel() {
InputVerifier verifier = new DateFieldVerifier();
checkInDateField.setInputVerifier(verifier);
checkOutDateField.setInputVerifier(verifier);
setLayout(new GridBagLayout());
for (int i = 0; i < fields.length; i++) {
add(new JLabel(labels[i] + ":"), createGbc(0, i));
add(fields[i], createGbc(1, i));
}
}
public String getName() {
return nameField.getText();
}
public String getEmail() {
return emailField.getText();
}
public Date getCheckOut() {
return (Date) checkOutDateField.getValue();
}
public Date getCheckIn() {
return (Date) checkInDateField.getValue();
}
public Form48Customer getForm48Customer() {
String name = getName();
Date checkOut = getCheckOut();
Date checkIn = getCheckIn();
String email = getEmail();
return new Form48Customer(name, checkIn, checkOut, email);
}
private GridBagConstraints createGbc(int x, int y) {
GridBagConstraints gbc = new GridBagConstraints();
gbc.gridx = x;
gbc.gridy = y;
gbc.weightx = 1.0;
gbc.weighty = 1.0;
gbc.insets = INSETS;
gbc.anchor = x == 0 ? GridBagConstraints.WEST :GridBagConstraints.EAST;
gbc.fill = GridBagConstraints.HORIZONTAL;
return gbc;
}
private class DateFieldVerifier extends InputVerifier {
#Override
public boolean verify(JComponent input) {
if (input instanceof JFormattedTextField) {
JFormattedTextField ftf = (JFormattedTextField)input;
AbstractFormatter formatter = ftf.getFormatter();
if (formatter != null) {
String text = ftf.getText();
try {
formatter.stringToValue(text);
return true;
} catch (ParseException pe) {
return false;
}
}
}
return true;
}
#Override
public boolean shouldYieldFocus(JComponent input) {
boolean verify = verify(input);
if (!verify) {
String message = "Enter a valid date, e.g.: 01/05/2017";
String title = "Invalid Date Format";
int type = JOptionPane.ERROR_MESSAGE;
JOptionPane.showMessageDialog(input, message, title, type);
}
return verify;
}
}
}
#SuppressWarnings("serial")
class Form48TableModel extends DefaultTableModel {
private static final String[] COL_NAMES = {"Name", "Check Out Date", "Check In Date", "Email"};
public Form48TableModel() {
super(COL_NAMES, 0);
}
public void addRow(Form48Customer customer) {
Object[] rowData = {
customer.getName(),
customer.getCheckOut(),
customer.getCheckIn(),
customer.getEmail()
};
addRow(rowData);
}
public Form48Customer getRow(int row) {
String name = (String) getValueAt(row, 0);
Date checkIn = (Date) getValueAt(row, 1);
Date checkOut = (Date) getValueAt(row, 2);
String email = (String) getValueAt(row, 3);
return new Form48Customer(name, checkIn, checkOut, email);
}
#Override
public Class<?> getColumnClass(int columnIndex) {
switch (columnIndex) {
case 1:
return Date.class;
case 2:
return Date.class;
default:
break;
}
return super.getColumnClass(columnIndex);
}
}
Which would look like:

Java swing BoxLayout center doesn't work

I have a JFrame that has JPanel inside. Inside JPanel there are 2 buttons. JPanel has a BoxLayout. I need buttons to be displayed horizontally in the center of the window. Here is my code:
I just create two buttons, set their alignment to the center (tried all the ways I knew) and add them to the panel horizontally.
public class UserInterface extends JFrame {
public UserInterface() {
setup();
}
private void setup() {
...
panel=new UserInterfacePanel();
add(panel);
}
}
class UserInterfacePanel extends JPanel {
private JToggleButton startButton;
private JToggleButton stopButton;
public UserInterfacePanel() {
setup();
}
private void setup() {
setLayout(new BoxLayout(this, BoxLayout.X_AXIS));
setupButtons();
setupButtonsActions();
add(startButton);
add(stopButton);
}
private void setupButtons() {
...
startButton.setHorizontalAlignment(JButton.CENTER);
stopButton.setHorizontalAlignment(JButton.CENTER);
startButton.setAlignmentX(CENTER_ALIGNMENT);
stopButton.setAlignmentX(CENTER_ALIGNMENT);
}
}
And yet it doesn't work. Why doesn't it and how to fix it?

buttons are still located at the left side of the window.
If you want the components center horizontally on the line you need to use "glue"
add(Box.createHorizontalGlue());
add(startButton);
add(stopButton);
add(Box.createHorizontalGlue());

You're setting the x alignment of the buttons but you're box layout lays out along the x axis -- doesn't make sense. Either set the y alignment and use the x axis for the box layout direction, or set the x alignment and use the y axis for the box layout direction.
e.g.,
private void setup() {
setLayout(new BoxLayout(this, BoxLayout.Y_AXIS)); // **** change ****
setupButtons();
// setupButtonsActions();
add(startButton);
add(stopButton);
}
private void setupButtons() {
// ...
startButton.setHorizontalAlignment(JButton.CENTER);
stopButton.setHorizontalAlignment(JButton.CENTER);
startButton.setAlignmentX(CENTER_ALIGNMENT);
stopButton.setAlignmentX(CENTER_ALIGNMENT);
}
or
private void setup() {
setLayout(new BoxLayout(this, BoxLayout.X_AXIS));
setupButtons();
// setupButtonsActions();
add(startButton);
add(stopButton);
}
private void setupButtons() {
// ...
startButton.setHorizontalAlignment(JButton.CENTER);
stopButton.setHorizontalAlignment(JButton.CENTER);
startButton.setAlignmentY(CENTER_ALIGNMENT); // **** change ****
stopButton.setAlignmentY(CENTER_ALIGNMENT); // **** change ****
}
To center all, use a different layout, such as a GridBagLayout:
import java.awt.Dimension;
import java.awt.GridBagConstraints;
import java.awt.GridBagLayout;
import java.awt.Insets;
import javax.swing.*;
#SuppressWarnings("serial")
public class UserInterfacePanel extends JPanel {
private static final Insets INSETS = new Insets(3, 3, 3, 3);
private static final int PREF_W = 800;
private static final int PREF_H = 650;
private JToggleButton startButton = new JToggleButton("Start");
private JToggleButton stopButton = new JToggleButton("Long Texted Title");
public UserInterfacePanel() {
setup();
}
private void setup() {
setLayout(new GridBagLayout()); // **** change
add(startButton, createGbc(0, 0));
add(stopButton, createGbc(1, 0));
}
private GridBagConstraints createGbc(int x, int y) {
GridBagConstraints gbc = new GridBagConstraints();
gbc.gridx = x;
gbc.gridy = y;
gbc.insets = INSETS;
return gbc;
}
#Override
public Dimension getPreferredSize() {
if (isPreferredSizeSet()) {
return super.getPreferredSize();
}
return new Dimension(PREF_W, PREF_H);
}
private static void createAndShowGui() {
UserInterfacePanel mainPanel = new UserInterfacePanel();
JFrame frame = new JFrame("UserInterfacePanel");
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.getContentPane().add(mainPanel);
frame.pack();
frame.setLocationRelativeTo(null);
frame.setVisible(true);
}
public static void main(String[] args) {
SwingUtilities.invokeLater(() -> createAndShowGui());
}
}

How to make this text area show which toggle buttons are selected?

Please can someone help me, I'm trying to make a seat reservation part for my cinema ticket system assignment ... so the problem is i want the text of the button to show in the text area when selected and not show only the specific text when deselected .. but when i deselect a button the whole text area is cleared.
For e.g. when I select C1, C2, C3 - it shows in the text area correctly, but if I want to deselect C3, the text area must now show only C1 & C2. Instead, it clears the whole text area!
Can anyone spot the problem in the logic?
import java.awt.*;
import static java.awt.Color.blue;
import javax.swing.*;
import java.awt.event.*;
import javax.swing.border.Border;
public class Cw_Test2 extends JFrame {
JButton btn_payment,btn_reset;
JButton buttons;
JTextField t1,t2;
public static void main(String[] args) {
// TODO code application logic here
new Cw_Test2();
}
public Cw_Test2()
{
Frame();
}
public void Frame()
{
this.setSize(1200,700); //width, height
this.setTitle("Seat Booking");
this.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
this.setLocationRelativeTo(null);
Font myFont = new Font("Serif", Font.ITALIC | Font.BOLD, 6);
Font newFont = myFont.deriveFont(20F);
t1=new JTextField();
t1.setBounds(15, 240, 240,30);
JPanel thePanel = new JPanel()
{
#Override
public Dimension getPreferredSize() {
return new Dimension(350, 350);
};
};
thePanel.setLayout(null);
JPanel ourPanel = new JPanel()
{
#Override
public Dimension getPreferredSize() {
return new Dimension(350, 350);
};
};
//ourPanel.setBackground(Color.green);
Border ourBorder = BorderFactory.createLineBorder(blue , 2);
ourPanel.setBorder(ourBorder);
ourPanel.setLayout(null);
ourPanel.setBounds(50,90, 1100,420);
JPanel newPanel = new JPanel()
{
#Override
public Dimension getPreferredSize() {
return new Dimension(350, 350);
};
};
//ourPanel.setBackground(Color.green);
Border newBorder = BorderFactory.createLineBorder(blue , 1);
newPanel.setBorder(newBorder);
newPanel.setLayout(null);
newPanel.setBounds(790,50, 270,340);
JLabel label1 = new JLabel( new ColorIcon(Color.GRAY, 400, 100) );
label1.setText( "SCREEN" );
label1.setHorizontalTextPosition(JLabel.CENTER);
label1.setVerticalTextPosition(JLabel.CENTER);
label1.setBounds(130,50, 400,30);
JLabel label2 = new JLabel(" CINEMA TICKET MACHINE ");
label2.setBounds(250,50,400,30);
label2.setFont(newFont);
JLabel label3 = new JLabel("Please Select Your Seat");
label3.setBounds(270,10,500,30);
label3.setFont(newFont);
JLabel label4 = new JLabel("Selected Seats:");
label4.setBounds(20,10,200,30);
label4.setFont(newFont);
btn_payment=new JButton("PROCEED TO PAY");
btn_payment.setBounds(35,290,200,30);
JLabel label6 = new JLabel("Center Stall");
label6.setBounds(285,172,200,30);
JPanel seatPane, seatPane1, seatPane2, seatPane3, seatPane4, seatPane5;
JToggleButton[] seat2 = new JToggleButton[8];
JTextArea chosen = new JTextArea();
chosen.setEditable(false);
chosen.setLineWrap(true);
chosen.setBounds(20, 60, 200, 100);
// Center Seats
seatPane1 = new JPanel();
seatPane1.setBounds(200,200,250,65);
seatPane1.setLayout(new FlowLayout());
for(int x=0; x<8; x++){
seat2[x] = new JToggleButton("C"+(x+1));
seatPane1.add(seat2[x]);
seat2[x].addActionListener(new ActionListener(){
public void actionPerformed(ActionEvent ev){
AbstractButton abstractButton = (AbstractButton) ev.getSource();
boolean selected = abstractButton.getModel().isSelected();
for(int x=0; x<8; x++){
if(seat2[x]==ev.getSource()){
if(selected){
chosen.append(seat2[x].getText()+",");
}else{
chosen.setText(seat2[x].getText().replace(seat2[x].getText(),""));
}
}
}
}
});
}
newPanel.add(chosen);
ourPanel.add(seatPane1);
ourPanel.add(label6);
thePanel.add(label2);
ourPanel.add(label3);
ourPanel.add(label1);
newPanel.add(btn_payment);
newPanel.add(label4);
ourPanel.add(newPanel);
thePanel.add(ourPanel);
add(thePanel);
setResizable(false);
this.setVisible(true);
}
public static class ColorIcon implements Icon
{
private Color color;
private int width;
private int height;
public ColorIcon(Color color, int width, int height)
{
this.color = color;
this.width = width;
this.height = height;
}
public int getIconWidth()
{
return width;
}
public int getIconHeight()
{
return height;
}
public void paintIcon(Component c, Graphics g, int x, int y)
{
g.setColor(color);
g.fillRect(x, y, width, height);
}
}

When any seat is selected or deselected, this code iterates an array of seats (in the method showSelectedSeats()) and updates the text area to show the seats that are selected.
import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
import javax.swing.border.*;
public class CinemaTicketMachine {
private JComponent ui = null;
private JToggleButton[] seats = new JToggleButton[80];
private JTextArea selectedSeats = new JTextArea(3, 40);
CinemaTicketMachine() {
initUI();
}
public void initUI() {
if (ui!=null) return;
ui = new JPanel(new BorderLayout(4,4));
ui.setBorder(new EmptyBorder(4,4,4,4));
selectedSeats.setLineWrap(true);
selectedSeats.setWrapStyleWord(true);
selectedSeats.setEditable(false);
ui.add(new JScrollPane(selectedSeats), BorderLayout.PAGE_END);
JPanel cinemaFloor = new JPanel(new BorderLayout(40, 0));
cinemaFloor.setBorder(new TitledBorder("Available Seats"));
ui.add(cinemaFloor, BorderLayout.CENTER);
JPanel leftStall = new JPanel(new GridLayout(0, 2, 2, 2));
JPanel centerStall = new JPanel(new GridLayout(0, 4, 2, 2));
JPanel rightStall = new JPanel(new GridLayout(0, 2, 2, 2));
cinemaFloor.add(leftStall, BorderLayout.WEST);
cinemaFloor.add(centerStall, BorderLayout.CENTER);
cinemaFloor.add(rightStall, BorderLayout.EAST);
ActionListener seatSelectionListener = new ActionListener() {
#Override
public void actionPerformed(ActionEvent e) {
showSelectedSeats();
}
};
for (int ii=0; ii <seats.length; ii++) {
JToggleButton tb = new JToggleButton("S-" + (ii+1));
tb.addActionListener(seatSelectionListener);
seats[ii] = tb;
int colIndex = ii%8;
if (colIndex<2) {
leftStall.add(tb);
} else if (colIndex<6) {
centerStall.add(tb);
} else {
rightStall.add(tb);
}
}
}
private void showSelectedSeats() {
StringBuilder sb = new StringBuilder();
for (int ii=0; ii<seats.length; ii++) {
JToggleButton tb = seats[ii];
if (tb.isSelected()) {
sb.append(tb.getText());
sb.append(", ");
}
}
String s = sb.toString();
if (s.length()>0) {
s = s.substring(0, s.length()-2);
}
selectedSeats.setText(s);
}
public JComponent getUI() {
return ui;
}
public static void main(String[] args) {
Runnable r = new Runnable() {
#Override
public void run() {
CinemaTicketMachine o = new CinemaTicketMachine();
JFrame f = new JFrame(o.getClass().getSimpleName());
f.setDefaultCloseOperation(JFrame.DISPOSE_ON_CLOSE);
f.setLocationByPlatform(true);
f.setContentPane(o.getUI());
f.pack();
f.setMinimumSize(f.getSize());
f.setVisible(true);
}
};
SwingUtilities.invokeLater(r);
}
}

Why JPanel.focusGaind and Lost don't work?

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.

Creating a window - but buttons layout error

I made a small program with two buttons. I label
the buttons one exiting the program and the second importing files.
I actually let them both to exit the program when ever someone pressed on it
the problem is the buttons taking all the window, why?
I tried GridBagConstraints to resize the buttons some how but no luck anyway here's the full class without imports..
public class Window2 extends JFrame{
private static final long serialVersionUID = 1L;
public Window2(){
super ("ALANAZ imagtor");
setSize(600,400);
setDefaultCloseOperation(EXIT_ON_CLOSE);
JPanel pnl1 = new JPanel(new GridLayout());
JPanel pnl2 = new JPanel();
//button
JButton butn1 = new JButton("EXIT");
JButton butn2 =new JButton("IMPORT");
butn1.addActionListener(new ActionListener() {
#Override
public void actionPerformed(ActionEvent e) {
// TODO Auto-generated method stub
JOptionPane.showMessageDialog(null, "exiting ... bye...");
System.exit(0);
}
});
butn2.addActionListener(new ActionListener(){
public void actionPerformed(ActionEvent ae){
JOptionPane.showMessageDialog(null, "can't import now exiting");
System.exit(0);
}
});
GridBagConstraints gb1 = new GridBagConstraints();
gb1.insets = new Insets(15,15,15,15);
//Jlabel
JLabel lbl1 = new JLabel("exit or import an image");
pnl1.add(butn1);
pnl1.add(butn2);
pnl2.add(lbl1);
add(pnl2, BorderLayout.SOUTH);
add(pnl1, BorderLayout.CENTER);
}}

You are misusing your layout managers. Your pnl1 JPanel uses GridLayout (without any row or column constants?!), and if you only add one component to it, it will take up the entire JPanel. You seem to have GridBagConstraints in your code, but no GridBagLayout, which is confusing to me.
The solution is to read up on and understand how to use layout managers. Please have a look at the tutorial link: Laying Out Components Within a Container.
Key is to keep remembering that you can nest JPanels within JPanels. For example:
import java.awt.BorderLayout;
import java.awt.Dimension;
import java.awt.GridLayout;
import java.awt.event.*;
import javax.swing.*;
public class Window2 extends JFrame {
private static final long serialVersionUID = 1L;
private static final int PREF_W = 600;
private static final int PREF_H = 400;
public Window2() {
super("ALANAZ imagtor");
setDefaultCloseOperation(EXIT_ON_CLOSE);
int gap = 3;
JPanel buttonPanel = new JPanel(new GridLayout(1, 0, gap, 0));
buttonPanel.setBorder(BorderFactory.createEmptyBorder(gap, gap, gap, gap));
JPanel pnl2 = new JPanel();
JButton butn1 = new JButton("EXIT");
JButton butn2 = new JButton("IMPORT");
butn1.addActionListener(new ActionListener() {
#Override
public void actionPerformed(ActionEvent e) {
JOptionPane.showMessageDialog(null, "exiting ... bye...");
System.exit(0);
}
});
butn2.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent ae) {
JOptionPane.showMessageDialog(null, "can't import now exiting");
System.exit(0);
}
});
JLabel lbl1 = new JLabel("exit or import an image");
buttonPanel.add(butn1);
buttonPanel.add(butn2);
JPanel centerPanel = new JPanel(new BorderLayout());
centerPanel.add(buttonPanel, BorderLayout.SOUTH);
pnl2.add(lbl1);
add(pnl2, BorderLayout.SOUTH);
add(centerPanel, BorderLayout.CENTER);
}
#Override
public Dimension getPreferredSize() {
return new Dimension(PREF_W, PREF_H);
}
public static void main(String[] args) {
Window2 win2 = new Window2();
win2.pack();
win2.setLocationRelativeTo(null);
win2.setVisible(true);
}
}

If you initialize your panel with a BorderLayout instead, and add your buttons using EAST, NORTH, WEST, SOUTH, you will have a quick fix - however I do also recommend reading up on layout managers
JPanel pnl1 = new JPanel(new BorderLayout());
pnl1.add(new JButton(), BorderLayout.SOUTH);