To toggle visibility with JCheckBox, use isVisible() method:JCheckBox toggleVisibility = new JCheckBox("Hide/Show"); toggleVisibility.setSelected(comboBox.isVisible()); toggleVisibility.addItemListener(e -> {    comboBox.setVisible(e.getStateChange() == ItemEvent.SELECTED); });The following is an example to hide and display JCombobox with a JCheckBox in Java:Exampleimport java.awt.BorderLayout; import java.awt.event.ItemEvent; import javax.swing.*; public class SwingDemo {    JFrame frame;    SwingDemo(){       frame = new JFrame("ComboBox");       String Sports[]={"Select", "Tennis", "Cricket", "Football"};       JComboBox comboBox = new JComboBox(Sports);       comboBox.setBounds(50, 50, 90, 20);       frame.add(comboBox, BorderLayout.CENTER);       JCheckBox toggleVisibility = new JCheckBox("Hide/Show");       toggleVisibility.setSelected(comboBox.isVisible());       toggleVisibility.addItemListener(e ... Read More

To disable the first index, on the click of a button, let us implement for index > 0 i.e. item 2:System.out.println("Index 0 (First Item) is disabled... "); comboBox.addItemListener(e -> {    if (comboBox.getSelectedIndex() > 0) {       System.out.println("Index = " + comboBox.getSelectedIndex());    } });By implementing above, we have disabled the first item.The following is an example to disable the first item on a JComboBox:Exampleimport javax.swing.*; public class SwingDemo {    JFrame frame;    SwingDemo(){       frame = new JFrame("ComboBox");       String Sports[]={"Select", "Tennis", "Cricket", "Football"};       JComboBox comboBox = new JComboBox(Sports); ... Read More

For JCheckBox, use the following to set tooltip text:checkBox1.setToolTipText("Sports Football"); checkBox2.setToolTipText("Sports Tennis");Tooltip text is visible whenever you will place cursor on that particular text.The following is an example. Here, we have set the tooltip text for both the sports:Exampleimport java.awt.*; import java.awt.event.*; import javax.swing.*; public class SwingDemo {    private JFrame mainFrame;    private JLabel headerLabel;    private JLabel statusLabel;    private JPanel controlPanel;    public SwingDemo(){       prepareGUI();    }    public static void main(String[] args){       SwingDemo swingControlDemo = new SwingDemo();       swingControlDemo.showCheckBoxDemo();    }    private void prepareGUI(){       ... Read More

To change the JLabel foreground and background color, use the following methods:JLabel label; label.setForeground(new Color(120, 90, 40)); label.setBackground(new Color(100, 20, 70));The following is an example to change JLabel background and foreground color:Exampleimport java.awt.Color; import java.awt.Font; import javax.swing.*; import javax.swing.border.Border; public class SwingDemo {    public static void main(String args[]) {       JFrame frame = new JFrame("Demo");       JLabel label;       label = new JLabel("This is demo label!", JLabel.RIGHT);       label.setVerticalAlignment(JLabel.TOP);       label.setFont(new Font("Verdana", Font.PLAIN, 15));       label.setForeground(new Color(120, 90, 40));       label.setBackground(new Color(100, 20, 70));   ... Read More

Use the setVerticalAlignment() method to align JLabel text vertically to the top:JLabel label = label.setVerticalAlignment(JLabel.TOP);The following is an example to align JLabel text vertically to the top:Exampleimport java.awt.Color; import java.awt.Font; import javax.swing.*; import javax.swing.border.Border; public class SwingDemo {    public static void main(String args[]) {       JFrame frame = new JFrame("Demo");       JLabel label;       label = new JLabel("This is demo label!");       label.setFont(new Font("Verdana", Font.PLAIN, 14));       label.setVerticalAlignment(JLabel.TOP);       Border border = BorderFactory.createLineBorder(Color.ORANGE);       label.setBorder(border);       frame.add(label);       frame.setSize(600,300);       frame.setVisible(true);    } }Output

Mnemonic key is set so that a user can use Keyboard keys to check a CheckBox. For example, a key can be set with ALT:checkBox1.setMnemonic(KeyEvent.VK_F); checkBox2.setMnemonic(KeyEvent.VK_T); checkBox3.setMnemonic(KeyEvent.VK_R); checkBox4.setMnemonic(KeyEvent.VK_C); checkBox5.setMnemonic(KeyEvent.VK_A);Above, we have set key ALT+F for checkbox 1, key ALT+T for checkBox2, etc.The following is an example. Here, we have set Mnemonic key for selection of each CheckBox:Exampleimport java.awt.*; import java.awt.event.*; import javax.swing.*; public class SwingDemo {    private JFrame mainFrame;    private JLabel headerLabel;    private JLabel statusLabel;    private JPanel controlPanel;    public SwingDemo(){       prepareGUI();    }    public static void main(String[] args){       ... Read More

Here, we have used ItemListener to handle JCheckBox events i.e. whenever any of the CheckBox is selected.For example; When any of the sports like Football CheckBox is checked, event is fired and a message is visible in the botton.The following is an example to handle JCheckBox events with an ItemListener:Exampleimport java.awt.*; import java.awt.event.*; import javax.swing.*; public class SwingDemo {    private JFrame mainFrame;    private JLabel headerLabel;    private JLabel statusLabel;    private JPanel controlPanel;    public SwingDemo(){       prepareGUI();    }    public static void main(String[] args){       SwingDemo swingControlDemo = new SwingDemo();     ... Read More

The following is an example to get or set the selection state of JCheckBox:Exampleimport java.awt.FlowLayout; import javax.swing.JCheckBox; import javax.swing.JFrame; public class SwingDemo extends JFrame {    public SwingDemo() {       setSize(500, 500);       setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);       setLayout(new FlowLayout(FlowLayout.CENTER));       JCheckBox checkBox = new JCheckBox("Demo");       checkBox.setSelected(true);       boolean sel = checkBox.isSelected();       if (sel)          System.out.println("Check box selected!");       getContentPane().add(checkBox);    }    public static void main(String[] args) {       new SwingDemo().setVisible(true);    } }OutputSince the checkbox is selected by default, the following output would be visible in EclipseIDE:

The following is an example to disable JCheckBox if not checked in Java:Exampleimport java.awt.event.ActionEvent; import java.awt.event.ActionListener; import javax.swing.JCheckBox; import javax.swing.JOptionPane; public class SwingDemo {    public static void main(String[] args) {       JCheckBox checkBox = new JCheckBox("Demo", true);       checkBox.addActionListener(new ActionListener() {          public void actionPerformed(ActionEvent e) {             if (checkBox.isEnabled())                checkBox.setEnabled(false);             else                checkBox.setEnabled(true);          }       });       JOptionPane.showMessageDialog(null, checkBox);    } }OutputNow, when you will uncheck the above checkbox, it will get disabled:

The following is an example to create JCheckBox from text in Swing:Exampleimport java.awt.FlowLayout; import javax.swing.JCheckBox; import javax.swing.JFrame; import javax.swing.JLabel; public class SwingDemo {    public static void main(String[] args) {       JCheckBox checkBox1 = new JCheckBox("Cricket");       JCheckBox checkBox2 = new JCheckBox("Squash");       JCheckBox checkBox3 = new JCheckBox("Football");       checkBox3.setSelected(true);       JCheckBox checkBox4 = new JCheckBox("Hockey");       JCheckBox checkBox5 = new JCheckBox("Fencing");       JCheckBox checkBox6 = new JCheckBox("Tennis");       JFrame frame = new JFrame();       frame.setLayout(new FlowLayout());       frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);   ... Read More