PROGRAMMING

m9/ JAVA
REMEMBERS




Last update:   27-07-2021

Designer

With Netbeans GUI Builder you can create user interface with drag and drop. You can switch between code and design (Editors: Source / Design) Add Swing containers in the Designer.
 
#JFrame Form
Netbeans > New Project ... Java
Package > New JFrame Form ... App
 
#Menu Bar
Frame: Menu Bar (add)
Menu: Menu Item (add)
 
# Panels
Frame: Tabbed Pane (add)
Tabbed Pane: Panel (add 3, change color background to panels)
Code Generated    (2/2)

Code Generated

The code behind will be like this
 
public class App extends javax.swing.JFrame {

    public App() {
        initComponents();
    }

    /**
     * This method is called from within the constructor to initialize the form.
     * WARNING: Do NOT modify this code. The content of this method is always
     * regenerated by the Form Editor.
     */
    @SuppressWarnings("unchecked")
    // <editor-fold defaultstate="collapsed" desc="Generated Code">                          
    private void initComponents() {

        jMenuBar1 = new javax.swing.JMenuBar();
        jMenu1 = new javax.swing.JMenu();
        jMenuItem2 = new javax.swing.JMenuItem();
        jMenu2 = new javax.swing.JMenu();

        setDefaultCloseOperation(javax.swing.WindowConstants.EXIT_ON_CLOSE);

        jMenu1.setText("File");

        jMenuItem2.setAccelerator(javax.swing.KeyStroke.getKeyStroke(
                java.awt.event.KeyEvent.VK_O, java.awt.event.InputEvent.CTRL_MASK)
        );
        jMenuItem2.setText("Open");
        jMenuItem2.addActionListener(new java.awt.event.ActionListener() {
            public void actionPerformed(java.awt.event.ActionEvent evt) {
                jMenuItem2ActionPerformed(evt);
            }
        });
        jMenu1.add(jMenuItem2);

        jMenuBar1.add(jMenu1);

        jMenu2.setText("Edit");
        jMenuBar1.add(jMenu2);

        setJMenuBar(jMenuBar1);

        javax.swing.GroupLayout layout = new javax.swing.GroupLayout(getContentPane());
        getContentPane().setLayout(layout);
        layout.setHorizontalGroup(
            layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
            .addGap(0, 293, Short.MAX_VALUE)
        );
        layout.setVerticalGroup(
            layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
            .addGap(0, 183, Short.MAX_VALUE)
        );

        pack();
    }// </editor-fold>                        

    private void jMenuItem2ActionPerformed(java.awt.event.ActionEvent evt) {                                           
        // TODO add your handling code here:
    }                                          

    /**
     * @param args the command line arguments
     */
    public static void main(String args[]) {

        /* Create and display the form */
        java.awt.EventQueue.invokeLater(new Runnable() {
            public void run() {
                new App().setVisible(true);
            }
        });
    }

    // Variables declaration - do not modify                     
    private javax.swing.JMenu jMenu1;
    private javax.swing.JMenu jMenu2;
    private javax.swing.JMenuBar jMenuBar1;
    private javax.swing.JMenuItem jMenuItem2;
    // End of variables declaration                   
}
... 59 lines
 

Code Custom

Add code to attach menu to Tabbed Pane. When you select File > Open the second panel is displayed.
 
import java.awt.BorderLayout;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import javax.swing.JPanel;

public class App extends javax.swing.JFrame {

    public App() {
        initComponents();
        
        changePanel(jPanel1);  // --- Look Here
    jMenuItem2.addActionListener(new MenuAction(jPanel2));
    }
    
    private class MenuAction implements ActionListener {

    private JPanel panel;
    private MenuAction(JPanel panel) {
        this.panel = panel;
    }

    @Override
    public void actionPerformed(ActionEvent e) {
        changePanel(panel);
    }
    }
    
    public void changePanel(JPanel panel) {
    getContentPane().removeAll();
    getContentPane().add(panel, BorderLayout.CENTER);
    getContentPane().doLayout();
    validate();
    repaint();
    }

    /**
     * This method is called from within the constructor to initialize the form.
     * WARNING: Do NOT modify this code. The content of this method is always
     * regenerated by the Form Editor.
     */
    @SuppressWarnings("unchecked")
    // <editor-fold defaultstate="collapsed" desc="Generated Code">                          
    private void initComponents() {

        jTabbedPane1 = new javax.swing.JTabbedPane();
        jPanel1 = new javax.swing.JPanel();
        jPanel2 = new javax.swing.JPanel();
        jPanel3 = new javax.swing.JPanel();
        jMenuBar1 = new javax.swing.JMenuBar();
        jMenu1 = new javax.swing.JMenu();
        jMenuItem2 = new javax.swing.JMenuItem();
        jMenu2 = new javax.swing.JMenu();

        setDefaultCloseOperation(javax.swing.WindowConstants.EXIT_ON_CLOSE);

        jTabbedPane1.setBackground(new java.awt.Color(255, 0, 0));

        javax.swing.GroupLayout jPanel1Layout = new javax.swing.GroupLayout(jPanel1);
        jPanel1.setLayout(jPanel1Layout);
        jPanel1Layout.setHorizontalGroup(
            jPanel1Layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
            .addGap(0, 272, Short.MAX_VALUE)
        );
        jPanel1Layout.setVerticalGroup(
            jPanel1Layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
            .addGap(0, 140, Short.MAX_VALUE)
        );

        jTabbedPane1.addTab("tab1", jPanel1);

        jPanel2.setBackground(new java.awt.Color(255, 0, 51));

        javax.swing.GroupLayout jPanel2Layout = new javax.swing.GroupLayout(jPanel2);
        jPanel2.setLayout(jPanel2Layout);
        jPanel2Layout.setHorizontalGroup(
            jPanel2Layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
            .addGap(0, 272, Short.MAX_VALUE)
        );
        jPanel2Layout.setVerticalGroup(
            jPanel2Layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
            .addGap(0, 140, Short.MAX_VALUE)
        );

        jTabbedPane1.addTab("tab2", jPanel2);

        javax.swing.GroupLayout jPanel3Layout = new javax.swing.GroupLayout(jPanel3);
        jPanel3.setLayout(jPanel3Layout);
        jPanel3Layout.setHorizontalGroup(
            jPanel3Layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
            .addGap(0, 272, Short.MAX_VALUE)
        );
        jPanel3Layout.setVerticalGroup(
            jPanel3Layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
            .addGap(0, 140, Short.MAX_VALUE)
        );

        jTabbedPane1.addTab("tab3", jPanel3);

        jMenu1.setText("File");

        jMenuItem2.setAccelerator(javax.swing.KeyStroke.getKeyStroke(java.awt.event.KeyEvent.VK_O, java.awt.event.InputEvent.CTRL_MASK));
        jMenuItem2.setText("Open");
        jMenuItem2.addActionListener(new java.awt.event.ActionListener() {
            public void actionPerformed(java.awt.event.ActionEvent evt) {
                jMenuItem2ActionPerformed(evt);
            }
        });
        jMenu1.add(jMenuItem2);

        jMenuBar1.add(jMenu1);

        jMenu2.setText("Edit");
        jMenuBar1.add(jMenu2);

        setJMenuBar(jMenuBar1);

        javax.swing.GroupLayout layout = new javax.swing.GroupLayout(getContentPane());
        getContentPane().setLayout(layout);
        layout.setHorizontalGroup(
            layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
            .addGroup(layout.createSequentialGroup()
                .addContainerGap()
                .addComponent(jTabbedPane1, javax.swing.GroupLayout.PREFERRED_SIZE, 272, javax.swing.GroupLayout.PREFERRED_SIZE)
                .addContainerGap(16, Short.MAX_VALUE))
        );
        layout.setVerticalGroup(
            layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
            .addGroup(javax.swing.GroupLayout.Alignment.TRAILING, layout.createSequentialGroup()
                .addGap(0, 14, Short.MAX_VALUE)
                .addComponent(jTabbedPane1, javax.swing.GroupLayout.PREFERRED_SIZE, 169, javax.swing.GroupLayout.PREFERRED_SIZE))
        );

        pack();
    }// </editor-fold>                        

    private void jMenuItem2ActionPerformed(java.awt.event.ActionEvent evt) {                                           
        // TODO add your handling code here:
    }                                          

    /**
     * @param args the command line arguments
     */
    public static void main(String args[]) {

        /* Create and display the form */
        java.awt.EventQueue.invokeLater(new Runnable() {
            public void run() {
                new App().setVisible(true);
            }
        });
    }

    // Variables declaration - do not modify                     
    private javax.swing.JMenu jMenu1;
    private javax.swing.JMenu jMenu2;
    private javax.swing.JMenuBar jMenuBar1;
    private javax.swing.JMenuItem jMenuItem2;
    private javax.swing.JPanel jPanel1;
    private javax.swing.JPanel jPanel2;
    private javax.swing.JPanel jPanel3;
    private javax.swing.JTabbedPane jTabbedPane1;
    // End of variables declaration                   
}
... 128 lines
 

Questions    
Streams IO

        A B C D E F
🔔
1/1