To prevent resizing columns, use the method setResizingAllowed(). Here, we will set setResizingAllowed() to false for table header to disallow resizing of columns from header −table.getTableHeader().setResizingAllowed(false);Let us first see an example wherein we can easily resize columns in a table by resizing the table column header −Examplepackage my; import java.awt.Color; import java.awt.Font; import javax.swing.JFrame; import javax.swing.JScrollPane; import javax.swing.JTable; import javax.swing.table.DefaultTableModel; public class SwingDemo {    public static void main(String[] argv) throws Exception {       DefaultTableModel tableModel = new DefaultTableModel();       JTable table = new JTable(tableModel);       tableModel.addColumn("Language/ Technology");       tableModel.addColumn("Text Tutorial");   ... Read More

To highlight a row in a table, you can use the addRowSelectionInterval() method. At first create a table −DefaultTableModel tableModel = new DefaultTableModel(); JTable table = new JTable(tableModel);Add some columns −tableModel.addColumn("Language/ Technology"); tableModel.addColumn("Text Tutorial"); tableModel.addColumn("Video Tutorial"); tableModel.addColumn("Views");Now, add rows to the table −tableModel.addRow(new Object[] { "NodeJS", "No", "Yes", "2350"}); tableModel.addRow(new Object[] { "MVC", "Yes", "No", "1500"}); tableModel.addRow(new Object[] { "ASP.NET", "Yes", "Yes", "3400"}); tableModel.addRow(new Object[] { "F#", "Yes", "No", "7890"}); tableModel.addRow(new Object[] { "Blockchain", "Yes", "No", "10600"}); tableModel.addRow(new Object[] { "SharePoint", "Yes", "Yes", "4900"});Highlight a single row by adding interval of rows. Set the same index for both the parameters ... Read More

Use FlowLayout.CENTER to lay out components in a flow to be centered with FlowLayout. The following is an example to lay out components in a flow to be centered with FlowLayout −Examplepackage my; import java.awt.Color; import java.awt.Dimension; import java.awt.FlowLayout; import java.awt.Font; import javax.swing.JFrame; import javax.swing.JLabel; import javax.swing.JTextArea; import javax.swing.WindowConstants; public class SwingDemo {    public static void main(String[] args) {       JFrame frame = new JFrame("WorldCup2019");       frame.setLayout(new FlowLayout(FlowLayout.CENTER));       JLabel label = new JLabel("WorldCup Hosting Country ");       label.setPreferredSize(new Dimension(220, 70));       label.setOpaque(true);       label.setBackground(Color.ORANGE);     ... Read More

Yes, we can hide the header from a table. Use the setTableHeader() method and set it to null -table.setTableHeader(null);Above, the table is our JTable -JTable table = new JTable(marks, col)The following is an example to hide the table header -Examplepackage my; import java.awt.Color; import java.awt.Font; import javax.swing.JFrame; import javax.swing.JScrollPane; import javax.swing.JTable; import javax.swing.table.JTableHeader; public class SwingDemo {    public static void main(String[] argv) throws Exception {       Integer[][] marks = {          { 70, 66, 76, 89, 67, 98 },          { 67, 89, 64, 78, 59, 78 },       ... Read More

To change the table header font, you need to first get the header -JTableHeader tableHeader = table.getTableHeader();Now, use the Font class to set the new font. Here, we have set the font face to be Verdana, style as PLAIN and font size as 14 -Font headerFont = new Font("Verdana", Font.PLAIN, 14);Now, set this font to table header -tableHeader.setFont(headerFont);The following is an example to change the header font -Examplepackage my; import java.awt.Color; import java.awt.Font; import javax.swing.JFrame; import javax.swing.JScrollPane; import javax.swing.JTable; import javax.swing.table.JTableHeader; public class SwingDemo {    public static void main(String[] argv) throws Exception {       Integer[][] marks = ... Read More

Let’s say we have following MenuBar and menu in it -JMenuBar menuBar = new JMenuBar(); UIManager.put("MenuBar.background", Color.ORANGE); JMenu fileMenu = new JMenu("File"); fileMenu.setMnemonic(KeyEvent.VK_F); menuBar.add(fileMenu);Now, we will create a MenuItem and separate it using the JSeparator():JMenuItem menuItem1 = new JMenuItem("New", KeyEvent.VK_N); fileMenu.add(menuItem1); // separating MenuItems fileMenu.add(new JSeparator());The following is an example to separate Menu Items in a Menu with Java -Examplepackage my; import java.awt.Color; import java.awt.event.KeyEvent; import javax.swing.JFrame; import javax.swing.JMenu; import javax.swing.JMenuBar; import javax.swing.JMenuItem; import javax.swing.JSeparator; import javax.swing.UIManager; public class SwingDemo {    public static void main(final String args[]) {       JFrame frame = new JFrame("MenuBar Demo");     ... Read More

Use the UIManager to customize the MenuBar:JMenuBar menuBar = new JMenuBar(); UIManager.put("MenuBar.background", Color.ORANGE);We have used the following above to update the background color of the MenuBar:UIManager.put("MenuBar.background", Color.ORANGE);The following is an example to customize MenuBar and change the background color:package my; import java.awt.Color; import java.awt.event.KeyEvent; import javax.swing.JFrame; import javax.swing.JMenu; import javax.swing.JMenuBar; import javax.swing.JMenuItem; import javax.swing.UIManager; public class SwingDemo {    public static void main(final String args[]) {       JFrame frame = new JFrame("MenuBar Demo");       frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);       JMenuBar menuBar = new JMenuBar();       UIManager.put("MenuBar.background", Color.ORANGE);       JMenu fileMenu = new JMenu("File"); ... Read More

Contigous selection means sharing borders like selecting siblings of a node in a JTree. To allow contiguous selection of nodes, set the selection mode to CONTIGUOUS_TREE_SELECTION −tree.getSelectionModel().setSelectionMode(TreeSelectionModel.CONTIGUOUS_TREE_SELECTION);The following is an example to allow contigous selection of nodes in a JTree −Examplepackage my; import javax.swing.JFrame; import javax.swing.JTree; import javax.swing.tree.DefaultMutableTreeNode; import javax.swing.tree.TreeSelectionModel; public class SwingDemo {    public static void main(String[] args) throws Exception {       JFrame frame = new JFrame("Demo");       DefaultMutableTreeNode node = new DefaultMutableTreeNode("Products");       DefaultMutableTreeNode node1 = new DefaultMutableTreeNode("Clothing");       DefaultMutableTreeNode node2 = new DefaultMutableTreeNode("Electronics");       DefaultMutableTreeNode node3 = new DefaultMutableTreeNode("Home Decor");       DefaultMutableTreeNode node4 = new DefaultMutableTreeNode("Furniture");       node.add(node1);       node.add(node2);       node.add(node3);       node.add(node4);       DefaultMutableTreeNode one = new DefaultMutableTreeNode("Shirt");       DefaultMutableTreeNode two = new DefaultMutableTreeNode("Trousers");       ... Read More

Let us first create a table with rows and columns −String data[][] = { {"Australia", "5", "1"},    {"US", "10", "2"},    {"Canada", "9", "3"},    {"India", "7", "4"},    {"Poland", "2", "5"},    {"SriLanka", "5", "6"} }; String col [] = {"Team", "Selected Players", "Rank"}; DefaultTableModel tableModel = new DefaultTableModel(data, col); JTable table = new JTable(tableModel);Now, we will disable resizing of columns by dragging headers −table.getTableHeader().setResizingAllowed(false);The following is an example to disallow resizing a column by dragging between headers in a JTable: −Examplepackage my; import java.awt.Dimension; import javax.swing.JFrame; import javax.swing.JPanel; import javax.swing.JRootPane; import javax.swing.JScrollPane; import javax.swing.JTable; import javax.swing.table.DefaultTableModel; public ... Read More

Set the selection mode to SINGLE_TREE_SELECTION, if you want only a single tree node to be selected −tree.getSelectionModel().setSelectionMode(TreeSelectionModel.SINGLE_TREE_SELECTION);The following is an example to allow only a single tree node to be selected in a JTree −Examplepackage my; import javax.swing.JFrame; import javax.swing.JTree; import javax.swing.tree.DefaultMutableTreeNode; import javax.swing.tree.TreeSelectionModel; public class SwingDemo {    public static void main(String[] args) throws Exception {       JFrame frame = new JFrame("Demo");       DefaultMutableTreeNode node = new DefaultMutableTreeNode("Products");       DefaultMutableTreeNode node1 = new DefaultMutableTreeNode("Clothing");       DefaultMutableTreeNode node2 = new DefaultMutableTreeNode("Electronics");       DefaultMutableTreeNode node3 = new DefaultMutableTreeNode("Home Decor");   ... Read More