Develop Reference

JList Swing adding description to List Item

I am trying to create a JList with a small arrow next to it. When clicked, I want some content associated with the list item shown in the same List/Panel. The picture, I hope, gives a clear idea of what I am trying to achieve.
How do I do this ? Also, what is the small triangle feature to the left known as (for future search tags) ?

I hope this is what you meant. The arrowButton is a JToggleButton which, when activated, displays a JWindow containing information about the selected value of the JList. This JWindow will remain visible until the JToggleButtons state is set back to unselected again. The ListPanel class should be reusable in your code.
Code:
import java.awt.BorderLayout;
import java.awt.Color;
import java.awt.EventQueue;
import java.awt.FlowLayout;
import java.awt.Font;
import java.awt.Insets;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.awt.event.ComponentAdapter;
import java.awt.event.ComponentEvent;
import java.util.ArrayList;
import javax.swing.BorderFactory;
import javax.swing.Box;
import javax.swing.DefaultListModel;
import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JList;
import javax.swing.JOptionPane;
import javax.swing.JPanel;
import javax.swing.JScrollPane;
import javax.swing.JTextArea;
import javax.swing.JTextField;
import javax.swing.JTextPane;
import javax.swing.JToggleButton;
import javax.swing.JWindow;
import javax.swing.SwingUtilities;
import javax.swing.Timer;
public class Example {
public Example() {
JFrame frame = new JFrame();
ArrayList<Object> elements = new ArrayList<Object>();
ArrayList<String> texts = new ArrayList<String>();
ListPanel listPanel = new ListPanel(elements, texts);
JButton addButton = new JButton("Add");
addButton.addActionListener(new ActionListener() {
#Override
public void actionPerformed(ActionEvent arg0) {
JTextField elementField = new JTextField(5);
JTextArea textArea = new JTextArea(5, 10);
JPanel panel = new JPanel();
panel.add(new JLabel("Element:"));
panel.add(elementField);
panel.add(Box.createHorizontalStrut(15));
panel.add(new JLabel("Text:"));
panel.add(new JScrollPane(textArea));
int result = JOptionPane.showConfirmDialog(frame, panel, "Element & Text",
JOptionPane.OK_CANCEL_OPTION);
if (result == JOptionPane.OK_OPTION) {
listPanel.addElementToList(elementField.getText(), textArea.getText());
}
}
});
JButton deleteButton = new JButton("Remove");
deleteButton.addActionListener(new ActionListener() {
#Override
public void actionPerformed(ActionEvent e) {
if (listPanel.getList().getSelectedValue() != null) {
listPanel.removeElementFromList(listPanel.getList().getSelectedValue());
}
}
});
JPanel buttonPanel = new JPanel();
buttonPanel.add(addButton);
buttonPanel.add(deleteButton);
frame.add(listPanel);
frame.add(buttonPanel, BorderLayout.SOUTH);
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.pack();
frame.setLocationRelativeTo(null);
frame.setVisible(true);
}
public static void main(String[] args) {
EventQueue.invokeLater(new Runnable() {
#Override
public void run() {
new Example();
}
});
}
}
class ListPanel extends JPanel {
private JList<Object> list;
private JToggleButton arrowButton;
private ArrayList<String> texts;
private JWindow popup;
public ListPanel(ArrayList<Object> elements, ArrayList<String> texts) {
this.texts = texts;
popup = new JWindow();
arrowButton = new JToggleButton("\u25B6");
arrowButton.setMargin(new Insets(0, 0, 0, 0));
arrowButton.addActionListener(new ActionListener() {
#Override
public void actionPerformed(ActionEvent arg0) {
if (arrowButton.isSelected()) {
Object value = list.getSelectedValue();
if (value != null) {
JLabel titleLabel = new JLabel(value.toString());
titleLabel.setBackground(Color.WHITE);
titleLabel.setFont(new Font(Font.SANS_SERIF, Font.BOLD, 14));
titleLabel.setHorizontalAlignment(JLabel.LEFT);
JPanel titlePanel = new JPanel(new FlowLayout(FlowLayout.LEFT));
titlePanel.setBackground(Color.WHITE);
titlePanel.add(titleLabel);
JTextPane textPane = new JTextPane();
textPane.setEditable(false);
textPane.setText(texts.get(list.getSelectedIndex()));
JPanel contentPanel = new JPanel(new BorderLayout());
contentPanel.setBorder(BorderFactory.createLineBorder(Color.BLACK));
contentPanel.add(titlePanel, BorderLayout.NORTH);
contentPanel.add(textPane);
popup.setLocation(arrowButton.getLocationOnScreen().x + arrowButton.getWidth(),
arrowButton.getLocationOnScreen().y);
popup.setContentPane(contentPanel);
popup.revalidate();
popup.pack();
popup.setVisible(true);
}
} else {
if (popup.isVisible()) {
popup.setVisible(false);
}
}
}
});
Timer timer = new Timer(100, null);
timer.addActionListener(new ActionListener() {
#Override
public void actionPerformed(ActionEvent e) {
if (((JFrame) SwingUtilities.getWindowAncestor(ListPanel.this)) != null) {
activateComponentListener();
timer.stop();
}
}
});
timer.start();
list = new JList<Object>(new DefaultListModel<Object>());
for (Object element : elements) {
((DefaultListModel<Object>) list.getModel()).addElement(element);
}
JPanel buttonPanel = new JPanel(new BorderLayout());
buttonPanel.setBackground(Color.WHITE);
buttonPanel.add(arrowButton, BorderLayout.NORTH);
JScrollPane scrollPane = new JScrollPane(list);
scrollPane.setBorder(null);
setLayout(new BorderLayout());
setBorder(BorderFactory.createLineBorder(Color.BLACK));
add(scrollPane);
add(buttonPanel, BorderLayout.WEST);
}
private void activateComponentListener() {
((JFrame) SwingUtilities.getWindowAncestor(this)).addComponentListener(new ComponentAdapter() {
#Override
public void componentMoved(ComponentEvent arg0) {
if (popup.isVisible()) {
popup.setLocation(arrowButton.getLocationOnScreen().x + arrowButton.getWidth(),
arrowButton.getLocationOnScreen().y);
}
}
});
}
public void removeElementFromList(Object element) {
int index = getElementIndex(element);
if (((DefaultListModel<Object>) getList().getModel()).getElementAt(getElementIndex(element)) != null) {
((DefaultListModel<Object>) getList().getModel()).removeElementAt(index);
getTexts().remove(index);
}
}
public void removeElementFromList(int index) {
if (((DefaultListModel<Object>) getList().getModel()).getElementAt(index) != null) {
((DefaultListModel<Object>) getList().getModel()).removeElementAt(index);
getTexts().remove(index);
}
}
private Integer getElementIndex(Object element) {
for (int i = 0; i < ((DefaultListModel<Object>) getList().getModel()).getSize(); i++) {
if (((DefaultListModel<Object>) getList().getModel()).getElementAt(i).equals(element)) {
return i;
}
}
return null;
}
public void addElementToList(Object element, String text) {
((DefaultListModel<Object>) list.getModel()).addElement(element);
getTexts().add(text);
}
public JList<Object> getList() {
return list;
}
public JToggleButton getArrowButton() {
return arrowButton;
}
public ArrayList<String> getTexts() {
return texts;
}
}

JList Item Selection

I was wondering if there is a way, by selecting an item with a JList, to let the program perform some code. This code should run every time a new item is selected.
Previously, I had added a listener. Here is a minimal example I made.
public class Driver {
public static void main(String[] args) {
JFrame frame = new ListFrame();
frame.setVisible(true);
frame.setSize(200,100);
}
}
public class ListFrame extends JFrame {
private JList<String> list;
private JScrollPane scrollPane;
private String[] data = {"A","B","C"};
private JButton addButton = new JButton("Add");
public ListFrame() {
setLayout(new BorderLayout());
list = new JList<String>(data);
list.setSelectionMode(ListSelectionModel.SINGLE_SELECTION);
scrollPane = new JScrollPane(list);
add(scrollPane, BorderLayout.CENTER);
add(addButton, BorderLayout.SOUTH);
addButton.addActionListener(new ActionListener() {
#Override
public void actionPerformed(ActionEvent arg0) {
String newEntry = JOptionPane.showInputDialog("Add new entry.");
String[] tempData = new String[data.length + 1];
for(int i = 0; i < data.length; i++)
tempData[i] = data[i];
tempData[data.length] = newEntry;
data = tempData;
list = new JList<String>(data);
scrollPane.setViewportView(list);
}
});
list.addListSelectionListener(
new ListSelectionListener() {
#Override
public void valueChanged(ListSelectionEvent e) {
System.out.println("Hi");
}
});
}
}
However, when I click an item on the Jlist, nothing is printed.

Your example uses getSelectionModel() to get the the list's ListSelectionModel, and it adds your listener directly to the selection model. This bypasses the ListSelectionHandler, used internally by JList, which never gets a chance to fireSelectionValueChanged(). Instead, let JList add your listener:
list.addListSelectionListener(new ListSelectionListener() {...}
when I click an item on the JList, nothing is printed.
Your new example prints "Hi" when I click an item, but I see some problems:
Be sure to run on the event dispatch thread.
Check the ListSelectionEvent for details of what happened.
To add elements to the list, don't create a new JList; update the list's ListModel instead.
See How to Write a List Selection Listener for more; here's the example I tested.
import java.awt.BorderLayout;
import java.awt.EventQueue;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import javax.swing.DefaultListModel;
import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JList;
import javax.swing.JOptionPane;
import javax.swing.JScrollPane;
import javax.swing.ListSelectionModel;
import javax.swing.event.ListSelectionEvent;
import javax.swing.event.ListSelectionListener;
public class Driver {
public static void main(String[] args) {
EventQueue.invokeLater(() -> {
JFrame frame = new ListFrame();
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.pack();
frame.setVisible(true);
});
}
private static class ListFrame extends JFrame {
private final String[] data = {"A", "B", "C"};
private final DefaultListModel model = new DefaultListModel();
private final JList<String> list = new JList<>(model);
private final JButton addButton = new JButton("Add");
public ListFrame() {
for (String s : data) {
model.addElement(s);
}
list.setSelectionMode(ListSelectionModel.SINGLE_SELECTION);
add(new JScrollPane(list), BorderLayout.CENTER);
add(addButton, BorderLayout.SOUTH);
addButton.addActionListener(new ActionListener() {
#Override
public void actionPerformed(ActionEvent arg0) {
String newEntry = JOptionPane.showInputDialog("Add new entry.");
model.addElement(newEntry);
}
});
list.addListSelectionListener(new ListSelectionListener() {
#Override
public void valueChanged(ListSelectionEvent e) {
if (!e.getValueIsAdjusting()) {
System.out.println(e.getFirstIndex() + " " + e.getLastIndex());
}
}
});
}
}
}

Change JLabel colour repeatedly each time when JButton pressed

I'm trying to make a traffic light program, changing the foreground colour of JLabel from red to yellow to green, everytime I press JButton (i.e once i press JButton, JLabel turns red, then when i again press JButton it turns yellow and so on). But somehow the colour changes only once to red & nothing happens on further pressing JButton. Any kind of help would be appreciated. Thanks.
import java.awt.Color;
import java.awt.EventQueue;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.SwingConstants;
import java.awt.Font;
import javax.swing.JButton;
import java.awt.event.ActionListener;
import java.awt.event.ActionEvent;
import javax.swing.JTextField;
import java.awt.event.MouseAdapter;
import java.awt.event.MouseEvent;
public class traffic {
private JFrame frame;
/**
* Launch the application.
*/
public static void main(String[] args) {
EventQueue.invokeLater(new Runnable() {
public void run() {
try {
traffic window = new traffic();
window.frame.setVisible(true);
} catch (Exception e) {
e.printStackTrace();
}
}
});
}
/**
* Create the application.
*/
public traffic() {
initialize();
}
/**
* Initialize the contents of the frame.
*/
private void initialize() {
frame = new JFrame();
frame.setBounds(100, 100, 798, 512);
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.getContentPane().setLayout(null);
JLabel lblTrafficLight = new JLabel("Traffic Light");
lblTrafficLight.setFont(new Font("Tahoma", Font.BOLD, 40));
lblTrafficLight.setHorizontalAlignment(SwingConstants.CENTER);
lblTrafficLight.setBounds(190, 11, 403, 61);
frame.getContentPane().add(lblTrafficLight);
JLabel lblRed = new JLabel("RED");
lblRed.setHorizontalAlignment(SwingConstants.CENTER);
lblRed.setFont(new Font("Tahoma", Font.PLAIN, 40));
lblRed.setBounds(273, 125, 249, 61);
frame.getContentPane().add(lblRed);
JButton btnButton = new JButton("Button");
btnButton.setActionCommand("B");
btnButton.addMouseListener(new MouseAdapter() {
#Override
public void mouseClicked(MouseEvent arg0) {
if(btnButton.getActionCommand().equals("B"))
{
lblRed.setForeground(Color.RED);
}
if(btnButton.getActionCommand().equals("B"))
{
lblRed.setForeground(Color.YELLOW);
}
if(btnButton.getActionCommand().equals("B"))
{
lblRed.setForeground(Color.GREEN);
}
if(btnButton.getActionCommand().equals("B"))
{
lblRed.setForeground(Color.YELLOW);
}
if(btnButton.getActionCommand().equals("B"))
{
lblRed.setForeground(Color.RED);
}
}
});
btnButton.setBounds(353, 346, 89, 23);
frame.getContentPane().add(btnButton);
}
}

You're using the same actionCommand, B for each if block, and so all of the blocks will always run, and the last block will be the one seen.
e.g.,
int x = 1;
if (x == 1) {
// do something
}
if (x == 1) {
// do something else
}
all blocks will be done!
Either change the actionCommands used, or don't use actionCommand String but rather an incrementing int index. Also, don't use MouseListeners for JButtons but rather ActionListeners.
For example:
import java.awt.BorderLayout;
import java.awt.Color;
import java.awt.Dimension;
import java.awt.Font;
import java.awt.GridBagLayout;
import java.awt.event.ActionEvent;
import java.util.HashMap;
import java.util.Map;
import javax.swing.*;
public class Traffic2 extends JPanel {
private static final int PREF_W = 400;
private static final int PREF_H = 300;
private static final String[] STRINGS = {"Red", "Blue", "Orange", "Yellow", "Green", "Cyan"};
private Map<String, Color> stringColorMap = new HashMap<>();
private JLabel label = new JLabel("", SwingConstants.CENTER);
private int index = 0;
public Traffic2() {
stringColorMap.put("Red", Color.red);
stringColorMap.put("Blue", Color.blue);
stringColorMap.put("Orange", Color.orange);
stringColorMap.put("Yellow", Color.YELLOW);
stringColorMap.put("Green", Color.GREEN);
stringColorMap.put("Cyan", Color.CYAN);
label.setFont(label.getFont().deriveFont(Font.BOLD, 40f));
String key = STRINGS[index];
label.setText(key);
label.setForeground(stringColorMap.get(key));
JPanel centerPanel = new JPanel(new GridBagLayout());
centerPanel.add(label);
JPanel topPanel = new JPanel();
topPanel.add(new JButton(new AbstractAction("Change Color") {
#Override
public void actionPerformed(ActionEvent e) {
index++;
index %= STRINGS.length;
String key = STRINGS[index];
label.setText(key);
label.setForeground(stringColorMap.get(key));
}
}));
setLayout(new BorderLayout());
add(topPanel, BorderLayout.PAGE_START);
add(centerPanel, BorderLayout.CENTER);
}
#Override
public Dimension getPreferredSize() {
if (isPreferredSizeSet()) {
return super.getPreferredSize();
}
return new Dimension(PREF_W, PREF_H);
}
private static void createAndShowGui() {
Traffic2 mainPanel = new Traffic2();
JFrame frame = new JFrame("Traffic2");
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();
}
});
}
}

update components based on which tab its called from

Hello Guru's I am a beginner Java swing developer and am trying to build a simple app... here is a simplified version.
Setup: 1 JFrame, 2 BorderLayout based tabbed panels (A and B) each has 1 textfiled, shared JPanel class with combo box and ItemListener initialized in each tab's (North)
Issue: How to control updates to textfield's text based on which panel it came from eg. if I select Apples in TabA, the Item Listener updates the TextField on TabB as well. What I would like to accomplish is determine where the call came from TabA or TabB and only update the textfield associated with that tab.
Hope this makes some sense
public class Main extends JFrame {
private static final long serialVersionUID = 1L;
private JPanel contentPane;
public JTextField tfPanelA;
public JTextField tfPanelB;
/**
* Launch the application.
*/
public static void main(String[] args) {
EventQueue.invokeLater(new Runnable() {
public void run() {
try {
Main frame = new Main();
frame.setVisible(true);
} catch (Exception e) {
e.printStackTrace();
}
}
});
}
/**
* Create the frame.
*/
public Main() {
setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
setBounds(100, 100, 450, 300);
contentPane = new JPanel();
contentPane.setBorder(new EmptyBorder(5, 5, 5, 5));
contentPane.setLayout(new BorderLayout(0, 0));
setContentPane(contentPane);
JTabbedPane tabbedPane = new JTabbedPane(JTabbedPane.TOP);
contentPane.add(tabbedPane, BorderLayout.CENTER);
JPanel panelA = new JPanel();
tabbedPane.addTab("Tab A", null, panelA, null);
panelA.setLayout(new BorderLayout(0, 0));
sharedPanel s1 = new sharedPanel(this);
panelA.add(s1, BorderLayout.NORTH);
tfPanelA = new JTextField();
panelA.add(tfPanelA);
tfPanelA.setColumns(10);
JPanel panelB = new JPanel();
tabbedPane.addTab("Tab B", null, panelB, null);
panelB.setLayout(new BorderLayout(0, 0));
sharedPanel s2 = new sharedPanel(this);
panelB.add(s2, BorderLayout.NORTH);
tfPanelB = new JTextField();
panelB.add(tfPanelB);
tfPanelB.setColumns(10);
}
}
// Shared Class...
public class sharedPanel extends JPanel {
private Main app;
private String[] clist = {"Apples","Oranges","Bananas"};
/**
* Create the panel.
*/
public sharedPanel(final Main app) {
this.app=app;
setLayout(new FlowLayout(FlowLayout.CENTER, 5, 5));
JComboBox<String> comboBox = new JComboBox<String>();
comboBox.setModel(new DefaultComboBoxModel<String>(clist));
comboBox.addItemListener(new ItemListener() {
public void itemStateChanged(ItemEvent e) {
//update PanelA's textfield ONLY if called from PanelA
// do this if called from PanelA
app.tfPanelA.setText(e.getItem().toString());
// do this if called from PanelB
app.tfPanelB.setText(e.getItem().toString());
}
});
add(comboBox);
}
}

Since you have create a new instance of sharedPanel for each tab, simply provide a reference to the text field you want to be updated to it...
Which you end up with something more like...
public class sharedPanel extends JPanel {
private JTextField field;
private String[] clist = {"Apples","Oranges","Bananas"};
public sharedPanel(final JTextField field) {
this.field=field;
setLayout(new FlowLayout(FlowLayout.CENTER, 5, 5));
JComboBox<String> comboBox = new JComboBox<String>();
comboBox.setModel(new DefaultComboBoxModel<String>(clist));
comboBox.addItemListener(new ItemListener() {
public void itemStateChanged(ItemEvent e) {
sharedPanel.this.field.setText(e.getItem().toString());
}
});
add(comboBox);
}
}
Updated with a "model" example
This is very basic example of just one possible use of a model to bridge the changes between the common panel and other panels. This means that the common panel doesn't care about anything else and updates the supplied model, which fires events to interested parties who can take appropriate action as required.
import java.awt.BorderLayout;
import java.awt.EventQueue;
import java.awt.GridBagConstraints;
import java.awt.GridBagLayout;
import java.awt.event.ItemEvent;
import java.awt.event.ItemListener;
import java.util.ArrayList;
import java.util.List;
import javax.swing.DefaultComboBoxModel;
import javax.swing.JComboBox;
import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.JTabbedPane;
import javax.swing.JTextField;
import javax.swing.UIManager;
import javax.swing.UnsupportedLookAndFeelException;
import javax.swing.event.ChangeEvent;
import javax.swing.event.ChangeListener;
public class TabbedModel {
protected static final String[] MAIN_LIST = {"Apples","Oranges","Bananas"};
public static void main(String[] args) {
new TabbedModel();
}
public TabbedModel() {
EventQueue.invokeLater(new Runnable() {
#Override
public void run() {
try {
UIManager.setLookAndFeel(UIManager.getSystemLookAndFeelClassName());
} catch (ClassNotFoundException | InstantiationException | IllegalAccessException | UnsupportedLookAndFeelException ex) {
}
JTabbedPane tabPane = new JTabbedPane();
tabPane.addTab("A", new ATab());
tabPane.addTab("B", new ATab());
JFrame frame = new JFrame("Testing");
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.setLayout(new BorderLayout());
frame.add(tabPane);
frame.pack();
frame.setLocationRelativeTo(null);
frame.setVisible(true);
}
});
}
public class DefaultCommonModel implements CommonModel {
private List<ChangeListener> listeners;
private String value;
public DefaultCommonModel() {
listeners = new ArrayList<>(25);
}
#Override
public void addChangeListener(ChangeListener listener) {
listeners.add(listener);
}
#Override
public void removeChangeListener(ChangeListener listener) {
listeners.remove(listener);
}
#Override
public void setValue(String aValue) {
if (aValue == null ? value != null : !aValue.equals(value)) {
value = aValue;
fireStateChanged();
}
}
#Override
public String getValue() {
return value;
}
protected void fireStateChanged() {
if (!listeners.isEmpty()) {
ChangeEvent evt = new ChangeEvent(this);
for (ChangeListener listener : listeners) {
listener.stateChanged(evt);
}
}
}
}
public interface CommonModel {
public void addChangeListener(ChangeListener listener);
public void removeChangeListener(ChangeListener listener);
public void setValue(String value);
public String getValue();
}
public class CommonPanel extends JPanel {
private CommonModel model;
private JComboBox comboBox;
public CommonPanel(CommonModel model) {
this.model = model;
setLayout(new GridBagLayout());
comboBox = new JComboBox(new DefaultComboBoxModel<>(MAIN_LIST));
comboBox.addItemListener(new ItemListener() {
#Override
public void itemStateChanged(ItemEvent e) {
String value = (String) e.getItem();
CommonPanel.this.model.setValue(value);
}
});
add(comboBox);
}
}
public class ATab extends JPanel {
private List<JTextField> fields;
public ATab() {
setLayout(new GridBagLayout());
GridBagConstraints gbc = new GridBagConstraints();
gbc.gridwidth = GridBagConstraints.REMAINDER;
DefaultCommonModel model = new DefaultCommonModel();
model.addChangeListener(new ChangeListener() {
#Override
public void stateChanged(ChangeEvent e) {
CommonModel model = (CommonModel) e.getSource();
for (JTextField field : fields) {
field.setText(model.getValue());
}
}
});
CommonPanel commonPanel = new CommonPanel(model);
add(commonPanel, gbc);
fields = new ArrayList<>(25);
for (int index = 0; index < random(); index++) {
JTextField field = new JTextField(10);
add(field, gbc);
fields.add(field);
}
}
protected int random() {
return (int)Math.round(Math.random() * 9) + 1;
}
}
}

Since you have two instances of your SharedPanel you can add the textfield to be updated as a reference to the constructor:
SharedPanel s1 = new SharedPanel(this, tfPanelA);
and
public SharedPanel(final Main app, final JTextField tf) {
...
comboBox.addItemListener(new ItemListener() {
public void itemStateChanged(ItemEvent e) {
tf.setText(e.getItem().toString());
}
});
...
}

Applet not appearing full

I just created an applet
public class HomeApplet extends JApplet {
private static final long serialVersionUID = -7650916407386219367L;
//Called when this applet is loaded into the browser.
public void init() {
//Execute a job on the event-dispatching thread; creating this applet's GUI.
// setSize(400, 400);
try {
SwingUtilities.invokeAndWait(new Runnable() {
public void run() {
createGUI();
}
});
} catch (Exception e) {
System.err.println("createGUI didn't complete successfully");
}
}
private void createGUI() {
RconSection rconSection = new RconSection();
rconSection.setOpaque(true);
// CommandArea commandArea = new CommandArea();
// commandArea.setOpaque(true);
JTabbedPane tabbedPane = new JTabbedPane();
// tabbedPane.setSize(400, 400);
tabbedPane.addTab("Rcon Details", rconSection);
// tabbedPane.addTab("Commad Area", commandArea);
setContentPane(tabbedPane);
}
}
where the fisrt tab is:
package com.rcon;
import java.awt.BorderLayout;
import java.awt.GridLayout;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import javax.swing.JButton;
import javax.swing.JLabel;
import javax.swing.JOptionPane;
import javax.swing.JPanel;
import javax.swing.JTextField;
import com.Bean.RconBean;
import com.util.Utility;
public class RconSection extends JPanel implements ActionListener{
/**
*
*/
private static final long serialVersionUID = -9021500288377975786L;
private static String TEST_COMMAND = "test";
private static String CLEAR_COMMAND = "clear";
private static JTextField ipText = new JTextField();
private static JTextField portText = new JTextField();
private static JTextField rPassText = new JTextField();
// private DynamicTree treePanel;
public RconSection() {
// super(new BorderLayout());
JLabel ip = new JLabel("IP");
JLabel port = new JLabel("Port");
JLabel rPass = new JLabel("Rcon Password");
JButton testButton = new JButton("Test");
testButton.setActionCommand(TEST_COMMAND);
testButton.addActionListener(this);
JButton clearButton = new JButton("Clear");
clearButton.setActionCommand(CLEAR_COMMAND);
clearButton.addActionListener(this);
JPanel panel = new JPanel(new GridLayout(3,2));
panel.add(ip);
panel.add(ipText);
panel.add(port);
panel.add(portText);
panel.add(rPass);
panel.add(rPassText);
JPanel panel1 = new JPanel(new GridLayout(1,3));
panel1.add(testButton);
panel1.add(clearButton);
add(panel);
add(panel1);
// add(panel, BorderLayout.NORTH);
// add(panel1, BorderLayout.SOUTH);
}
#Override
public void actionPerformed(ActionEvent arg0) {
if(arg0.getActionCommand().equals(TEST_COMMAND)){
String ip = ipText.getText().trim();
if(!Utility.checkIp(ip)){
ipText.requestFocusInWindow();
ipText.selectAll();
JOptionPane.showMessageDialog(this,"Invalid Ip!!!");
return;
}
String port = portText.getText().trim();
if(port.equals("") || !Utility.isIntNumber(port)){
portText.requestFocusInWindow();
portText.selectAll();
JOptionPane.showMessageDialog(this,"Invalid Port!!!");
return;
}
String pass = rPassText.getText().trim();
if(pass.equals("")){
rPassText.requestFocusInWindow();
rPassText.selectAll();
JOptionPane.showMessageDialog(this,"Enter Rcon Password!!!");
return;
}
RconBean rBean = RconBean.getBean();
rBean.setIp(ip);
rBean.setPassword(pass);
rBean.setPort(Integer.parseInt(port));
if(!Utility.testConnection()){
rPassText.requestFocusInWindow();
rPassText.selectAll();
JOptionPane.showMessageDialog(this,"Invalid Rcon!!!");
return;
}else{
JOptionPane.showMessageDialog(this,"Correct Rcon!!!");
return;
}
}
else if(arg0.getActionCommand().equals(CLEAR_COMMAND)){
ipText.setText("");
portText.setText("");
rPassText.setText("");
}
}
}
it appears as
is has cropped some data how to display it full and make the applet non resizable as well. i tried setSize(400, 400); but it didnt helped the inner area remains the same and outer boundaries increases

Here's another variation on your layout. Using #Andrew's tag-in-source method, it's easy to test from the command line:
$ /usr/bin/appletviewer HomeApplet.java
// <applet code='HomeApplet' width='400' height='200'></applet>
import java.awt.BorderLayout;
import java.awt.GridLayout;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import javax.swing.JApplet;
import javax.swing.JButton;
import javax.swing.JLabel;
import javax.swing.JPanel;
import javax.swing.JTabbedPane;
import javax.swing.JTextField;
import javax.swing.SwingUtilities;
public class HomeApplet extends JApplet {
#Override
public void init() {
try {
SwingUtilities.invokeAndWait(new Runnable() {
#Override
public void run() {
createGUI();
}
});
} catch (Exception e) {
e.printStackTrace(System.err);
}
}
private void createGUI() {
JTabbedPane tabbedPane = new JTabbedPane();
tabbedPane.addTab("Rcon1", new RconSection());
tabbedPane.addTab("Rcon2", new RconSection());
this.add(tabbedPane);
}
private static class RconSection extends JPanel implements ActionListener {
private static final String TEST_COMMAND = "test";
private static final String CLEAR_COMMAND = "clear";
private JTextField ipText = new JTextField();
private JTextField portText = new JTextField();
private JTextField rPassText = new JTextField();
public RconSection() {
super(new BorderLayout());
JLabel ip = new JLabel("IP");
JLabel port = new JLabel("Port");
JLabel rPass = new JLabel("Rcon Password");
JButton testButton = new JButton("Test");
testButton.setActionCommand(TEST_COMMAND);
testButton.addActionListener(this);
JButton clearButton = new JButton("Clear");
clearButton.setActionCommand(CLEAR_COMMAND);
clearButton.addActionListener(this);
JPanel panel = new JPanel(new GridLayout(3, 2));
panel.add(ip);
panel.add(ipText);
panel.add(port);
panel.add(portText);
panel.add(rPass);
panel.add(rPassText);
JPanel buttons = new JPanel(); // default FlowLayout
buttons.add(testButton);
buttons.add(clearButton);
add(panel, BorderLayout.NORTH);
add(buttons, BorderLayout.SOUTH);
}
#Override
public void actionPerformed(ActionEvent e) {
System.out.println(e);
}
}
}

As I mentioned in a comment, this question is really about how to layout components in a container. This example presumes you wish to add the extra space to the text fields and labels. The size of the applet is set in the HTML.
200x130 200x150
/*
<applet
code='FixedSizeLayout'
width='200'
height='150'>
</applet>
*/
import java.awt.*;
import javax.swing.*;
public class FixedSizeLayout extends JApplet {
public void init() {
SwingUtilities.invokeLater(new Runnable() {
public void run() {
initGui();
}
});
}
private void initGui() {
JTabbedPane tb = new JTabbedPane();
tb.addTab("Rcon Details", new RconSection());
setContentPane(tb);
validate();
}
}
class RconSection extends JPanel {
private static String TEST_COMMAND = "test";
private static String CLEAR_COMMAND = "clear";
private static JTextField ipText = new JTextField();
private static JTextField portText = new JTextField();
private static JTextField rPassText = new JTextField();
public RconSection() {
super(new BorderLayout(3,3));
JLabel ip = new JLabel("IP");
JLabel port = new JLabel("Port");
JLabel rPass = new JLabel("Rcon Password");
JButton testButton = new JButton("Test");
testButton.setActionCommand(TEST_COMMAND);
JButton clearButton = new JButton("Clear");
clearButton.setActionCommand(CLEAR_COMMAND);
JPanel panel = new JPanel(new GridLayout(3,2));
panel.add(ip);
panel.add(ipText);
panel.add(port);
panel.add(portText);
panel.add(rPass);
panel.add(rPassText);
JPanel panel1 = new JPanel(new FlowLayout(FlowLayout.CENTER,5,5));
panel1.add(testButton);
panel1.add(clearButton);
add(panel, BorderLayout.CENTER);
add(panel1, BorderLayout.SOUTH);
}
public static void main(String[] args) {
SwingUtilities.invokeLater(new Runnable() {
public void run() {
Container c = new RconSection();
JOptionPane.showMessageDialog(null, c);
}
});
}
}

Size of applet viewer does not depend on your code.

JApplet is not window, so in java code you can't write japplet dimensions. You have to change run settings. I don't know where exactly are in other ide's, but in Eclipse you can change dimensions in Project Properties -> Run/Debug settings -> click on your launch configurations file (for me there were only 1 - main class) -> edit -> Parameters. There you can choose width and height for your applet. save changes and you are good to go