Auto-focus on a jButton on a jpanel

Question

I have a JPanel loaded on a JFrame. The JPanel contains 4 JButtons. The thing I am trying to do is to get the focus automatically on the 1st jbutton so that I can traverse between the JButtons with the keyboard.

I tried the jButton1.requestFocusInWindow(); code inside the constructor of the jpanel but still it didn't work. Is there something that i am missing? What more can i do?

Edit: The Project Contains 3 java files and their code is as follows:

NewJFrame.java

/*
 * To change this template, choose Tools | Templates
 * and open the template in the editor.
 */
package sampleui;

import java.awt.Container;
import java.awt.Toolkit;
import javax.swing.JRootPane;
import javax.swing.UIManager;

/**
 *
 * @author Administrator
 */
public class NewJFrame extends javax.swing.JFrame {

static Container container;

/**
 * Creates new form NewJFrame
 */
public NewJFrame() {
    initComponents();
    rootPane= getRootPane();
    container=getContentPane();
    setSize(Toolkit.getDefaultToolkit().getScreenSize());
    setVisible(true);

}

/**
 * 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() {

    jMenuItem1 = new javax.swing.JMenuItem();
    jPanel1 = new javax.swing.JPanel();
    jLabel2 = new javax.swing.JLabel();
    jLabel5 = new javax.swing.JLabel();
    jLabel6 = new javax.swing.JLabel();
    jLabel1 = new javax.swing.JLabel();
    jLabel3 = new javax.swing.JLabel();
    jPanel2 = new javax.swing.JPanel();
    jLabel7 = new javax.swing.JLabel();
    jLabel8 = new javax.swing.JLabel();
    jLabel9 = new javax.swing.JLabel();
    jDesktopPane1 = new javax.swing.JDesktopPane();

    jMenuItem1.setText("jMenuItem1");

    setDefaultCloseOperation(javax.swing.WindowConstants.EXIT_ON_CLOSE);
    setTitle("This is the Title");

    jPanel1.setBackground(new java.awt.Color(204, 204, 204));
    jPanel1.setLayout(new java.awt.BorderLayout());

    jLabel2.setForeground(new java.awt.Color(255, 255, 255));
    jPanel1.add(jLabel2, java.awt.BorderLayout.PAGE_START);

    jLabel5.setFont(new java.awt.Font("Tahoma", 1, 14)); // NOI18N
    jLabel5.setForeground(new java.awt.Color(51, 51, 51));
    jLabel5.setText("dfgdfgdfg");
    jPanel1.add(jLabel5, java.awt.BorderLayout.LINE_START);

    jLabel6.setFont(new java.awt.Font("Tahoma", 1, 14)); // NOI18N
    jLabel6.setText("dfgdfgdfg");
    jPanel1.add(jLabel6, java.awt.BorderLayout.LINE_END);

    jLabel1.setFont(new java.awt.Font("Tahoma", 1, 14)); // NOI18N
    jLabel1.setHorizontalAlignment(javax.swing.SwingConstants.CENTER);
    jLabel1.setText("dfgdfgfdgfdgfdg");
    jPanel1.add(jLabel1, java.awt.BorderLayout.CENTER);

    jLabel3.setHorizontalAlignment(javax.swing.SwingConstants.CENTER);
    jLabel3.setText("jLabel3");
    jPanel1.add(jLabel3, java.awt.BorderLayout.PAGE_END);

    getContentPane().add(jPanel1, java.awt.BorderLayout.PAGE_START);

    jPanel2.setBackground(new java.awt.Color(204, 204, 204));
    jPanel2.setLayout(new java.awt.BorderLayout());

    jLabel7.setText("jLabel7");
    jPanel2.add(jLabel7, java.awt.BorderLayout.LINE_START);

    jLabel8.setHorizontalAlignment(javax.swing.SwingConstants.TRAILING);
    jLabel8.setText("jLabel8");
    jPanel2.add(jLabel8, java.awt.BorderLayout.LINE_END);

    jLabel9.setHorizontalAlignment(javax.swing.SwingConstants.CENTER);
    jLabel9.setText("jLabel9");
    jPanel2.add(jLabel9, java.awt.BorderLayout.CENTER);

    getContentPane().add(jPanel2, java.awt.BorderLayout.PAGE_END);

    jDesktopPane1.addMouseListener(new java.awt.event.MouseAdapter() {
        public void mouseClicked(java.awt.event.MouseEvent evt) {
            jDesktopPane1MouseClicked(evt);
        }
    });
    getContentPane().add(jDesktopPane1, java.awt.BorderLayout.CENTER);

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

private void jDesktopPane1MouseClicked(java.awt.event.MouseEvent evt) {                                           
    // TODO add your handling code here:

    container=getContentPane();
    setSize(Toolkit.getDefaultToolkit().getScreenSize());
    setVisible(true);

    //callCompanyOption();

    container.setVisible(false);
    jDesktopPane1.setVisible(false);
    NewJPanel p=new NewJPanel();
    //p.setBounds(40, 30, 1200, 786);
    container.add(p);
    container.setVisible(true);

}                                          


/**
 * @param args the command line arguments
 */
public static void main(String args[]) {
    /* Set the Nimbus look and feel */
    //<editor-fold defaultstate="collapsed" desc=" Look and feel setting code (optional) ">
    /* If Nimbus (introduced in Java SE 6) is not available, stay with the default look and feel.
     * For details see http://download.oracle.com/javase/tutorial/uiswing/lookandfeel/plaf.html 
     */
    try {
        for (javax.swing.UIManager.LookAndFeelInfo info : javax.swing.UIManager.getInstalledLookAndFeels()) {
            if ("Nimbus".equals(info.getName())) {
                javax.swing.UIManager.setLookAndFeel(info.getClassName());
                break;
            }
        }
    } catch (ClassNotFoundException ex) {
        java.util.logging.Logger.getLogger(NewJFrame.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
    } catch (InstantiationException ex) {
        java.util.logging.Logger.getLogger(NewJFrame.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
    } catch (IllegalAccessException ex) {
        java.util.logging.Logger.getLogger(NewJFrame.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
    } catch (javax.swing.UnsupportedLookAndFeelException ex) {
        java.util.logging.Logger.getLogger(NewJFrame.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
    }
    //</editor-fold>

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



// Variables declaration - do not modify                     
private javax.swing.JDesktopPane jDesktopPane1;
private javax.swing.JLabel jLabel1;
private javax.swing.JLabel jLabel2;
private javax.swing.JLabel jLabel3;
private javax.swing.JLabel jLabel5;
private javax.swing.JLabel jLabel6;
private javax.swing.JLabel jLabel7;
private javax.swing.JLabel jLabel8;
private javax.swing.JLabel jLabel9;
private javax.swing.JMenuItem jMenuItem1;
private javax.swing.JPanel jPanel1;
private javax.swing.JPanel jPanel2;
// End of variables declaration                   
}

NewJPanel.java

/*
 * To change this template, choose Tools | Templates
 * and open the template in the editor.
 */
package sampleui;

import java.awt.Component;
import java.awt.Container;
import java.awt.event.KeyEvent;

/**
 *
 * @author Administrator
 */
public class NewJPanel extends javax.swing.JPanel {


/**
 * Creates new form NewJPanel
 */
public NewJPanel() {
    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() {

    jPanel2 = new javax.swing.JPanel();
    jPanel1 = new javax.swing.JPanel();
    jButton2 = new javax.swing.JButton();
    jXMonthView1 = new org.jdesktop.swingx.calendar.JXMonthView();

    setLayout(new java.awt.GridBagLayout());

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

    add(jPanel2, new java.awt.GridBagConstraints());

    jButton2.setText("OK");
    jButton2.setNextFocusableComponent(jButton2);
    jButton2.addMouseListener(new java.awt.event.MouseAdapter() {
        public void mouseClicked(java.awt.event.MouseEvent evt) {
            jButton2MouseClicked(evt);
        }
    });
    jButton2.addActionListener(new java.awt.event.ActionListener() {
        public void actionPerformed(java.awt.event.ActionEvent evt) {
            jButton2ActionPerformed(evt);
        }
    });
    jButton2.addKeyListener(new java.awt.event.KeyAdapter() {
        public void keyPressed(java.awt.event.KeyEvent evt) {
            jButton2KeyPressed(evt);
        }
    });

    jXMonthView1.addKeyListener(new java.awt.event.KeyAdapter() {
        public void keyPressed(java.awt.event.KeyEvent evt) {
            jXMonthView1KeyPressed(evt);
        }
    });

    javax.swing.GroupLayout jXMonthView1Layout = new javax.swing.GroupLayout(jXMonthView1);
    jXMonthView1.setLayout(jXMonthView1Layout);
    jXMonthView1Layout.setHorizontalGroup(
        jXMonthView1Layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
        .addGap(0, 0, Short.MAX_VALUE)
    );
    jXMonthView1Layout.setVerticalGroup(
        jXMonthView1Layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
        .addGap(0, 160, Short.MAX_VALUE)
    );

    javax.swing.GroupLayout jPanel1Layout = new javax.swing.GroupLayout(jPanel1);
    jPanel1.setLayout(jPanel1Layout);
    jPanel1Layout.setHorizontalGroup(
        jPanel1Layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
        .addGroup(jPanel1Layout.createSequentialGroup()
            .addGap(64, 64, 64)
            .addGroup(jPanel1Layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING, false)
                .addComponent(jButton2, javax.swing.GroupLayout.DEFAULT_SIZE, 217, Short.MAX_VALUE)
                .addComponent(jXMonthView1, javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.DEFAULT_SIZE, Short.MAX_VALUE))
            .addContainerGap(56, Short.MAX_VALUE))
    );
    jPanel1Layout.setVerticalGroup(
        jPanel1Layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
        .addGroup(jPanel1Layout.createSequentialGroup()
            .addGap(19, 19, 19)
            .addComponent(jXMonthView1, javax.swing.GroupLayout.PREFERRED_SIZE, javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.PREFERRED_SIZE)
            .addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.UNRELATED)
            .addComponent(jButton2, javax.swing.GroupLayout.PREFERRED_SIZE, 31, javax.swing.GroupLayout.PREFERRED_SIZE)
            .addContainerGap())
    );

    add(jPanel1, new java.awt.GridBagConstraints());
}// </editor-fold>

private void jButton2MouseClicked(java.awt.event.MouseEvent evt) {                                      

            jPanel1.setVisible(false);
            NewJFrame.container.remove(NewJPanel.this);
            NewJPanel1 p=new NewJPanel1();
            NewJFrame.container.add(p);


}                                     

private void jButton2KeyPressed(java.awt.event.KeyEvent evt) {                                    
    // TODO add your handling code here:
    int key=evt.getKeyCode();
    if(key==KeyEvent.VK_ENTER)
    {
        System.out.println("Enter Pressed");
        jPanel1.setVisible(false);
        NewJFrame.container.remove(NewJPanel.this);
        NewJPanel1 p=new NewJPanel1();
        NewJFrame.container.add(p);
    }
}                                   

private void jXMonthView1KeyPressed(java.awt.event.KeyEvent evt) {                                        
    // TODO add your handling code here:
    jButton2.requestFocus();
}                                       

private void jButton2ActionPerformed(java.awt.event.ActionEvent evt) {
    // TODO add your handling code here:
    jPanel1.setVisible(false);
        NewJFrame.container.remove(NewJPanel.this);
        NewJPanel1 p=new NewJPanel1();
        NewJFrame.container.add(p);
}


// Variables declaration - do not modify
private javax.swing.JButton jButton2;
private javax.swing.JPanel jPanel1;
private javax.swing.JPanel jPanel2;
private org.jdesktop.swingx.calendar.JXMonthView jXMonthView1;
// End of variables declaration
}

NewJPanel1.java

/*
 * To change this template, choose Tools | Templates
 * and open the template in the editor.
 */
 package sampleui;

 import java.awt.Window;
 import java.awt.event.KeyEvent;
 import javax.swing.JRootPane;

 /**
 *
 * @author Administrator
 */
 public class NewJPanel1 extends javax.swing.JPanel {


//=new NewJFrame();
/**
 * Creates new form NewJPanel1
 */
public NewJPanel1() {
    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() {

    jPanel1 = new javax.swing.JPanel();
    jButton1 = new javax.swing.JButton();
    jButton2 = new javax.swing.JButton();
    jButton3 = new javax.swing.JButton();
    jButton4 = new javax.swing.JButton();
    jButton5 = new javax.swing.JButton();

    setRequestFocusEnabled(false);
    addKeyListener(new java.awt.event.KeyAdapter() {
        public void keyPressed(java.awt.event.KeyEvent evt) {
            formKeyPressed(evt);
        }
    });
    setLayout(new java.awt.GridBagLayout());

    jPanel1.setNextFocusableComponent(jButton5);
    jPanel1.addKeyListener(new java.awt.event.KeyAdapter() {
        public void keyPressed(java.awt.event.KeyEvent evt) {
            jPanel1KeyPressed(evt);
        }
        public void keyReleased(java.awt.event.KeyEvent evt) {
            jPanel1KeyReleased(evt);
        }
    });

    jButton1.setText("back");
    jButton1.addMouseListener(new java.awt.event.MouseAdapter() {
        public void mouseClicked(java.awt.event.MouseEvent evt) {
            jButton1MouseClicked(evt);
        }
        public void mouseEntered(java.awt.event.MouseEvent evt) {
            jButton1MouseEntered(evt);
        }
    });
    jButton1.addKeyListener(new java.awt.event.KeyAdapter() {
        public void keyPressed(java.awt.event.KeyEvent evt) {
            jButton1KeyPressed(evt);
        }
    });

    jButton2.setText("jButton2");
    jButton2.addKeyListener(new java.awt.event.KeyAdapter() {
        public void keyPressed(java.awt.event.KeyEvent evt) {
            jButton2KeyPressed(evt);
        }
    });

    jButton3.setText("jButton3");
    jButton3.addKeyListener(new java.awt.event.KeyAdapter() {
        public void keyPressed(java.awt.event.KeyEvent evt) {
            jButton3KeyPressed(evt);
        }
    });

    jButton4.setText("jButton4");
    jButton4.addKeyListener(new java.awt.event.KeyAdapter() {
        public void keyPressed(java.awt.event.KeyEvent evt) {
            jButton4KeyPressed(evt);
        }
    });

    jButton5.setText("jButton5");
    jButton5.setCursor(new java.awt.Cursor(java.awt.Cursor.DEFAULT_CURSOR));
    jButton5.setFocusCycleRoot(true);
    jButton5.setFocusTraversalPolicyProvider(true);
    jButton5.setInheritsPopupMenu(true);
    jButton5.setNextFocusableComponent(jButton4);
    jButton5.setVerifyInputWhenFocusTarget(false);
    jButton5.requestFocusInWindow();
    jButton5.addActionListener(new java.awt.event.ActionListener() {
        public void actionPerformed(java.awt.event.ActionEvent evt) {
            jButton5ActionPerformed(evt);
        }
    });
    jButton5.addKeyListener(new java.awt.event.KeyAdapter() {
        public void keyPressed(java.awt.event.KeyEvent evt) {
            jButton5KeyPressed(evt);
        }
    });

    javax.swing.GroupLayout jPanel1Layout = new javax.swing.GroupLayout(jPanel1);
    jPanel1.setLayout(jPanel1Layout);
    jPanel1Layout.setHorizontalGroup(
        jPanel1Layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
        .addGroup(javax.swing.GroupLayout.Alignment.TRAILING, jPanel1Layout.createSequentialGroup()
            .addContainerGap(41, Short.MAX_VALUE)
            .addGroup(jPanel1Layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING, false)
                .addComponent(jButton1, javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.DEFAULT_SIZE, Short.MAX_VALUE)
                .addComponent(jButton2, javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.DEFAULT_SIZE, Short.MAX_VALUE)
                .addComponent(jButton3, javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.DEFAULT_SIZE, Short.MAX_VALUE)
                .addComponent(jButton4, javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.DEFAULT_SIZE, Short.MAX_VALUE)
                .addComponent(jButton5, javax.swing.GroupLayout.PREFERRED_SIZE, 126, javax.swing.GroupLayout.PREFERRED_SIZE))
            .addGap(38, 38, 38))
    );
    jPanel1Layout.setVerticalGroup(
        jPanel1Layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
        .addGroup(jPanel1Layout.createSequentialGroup()
            .addContainerGap()
            .addComponent(jButton5)
            .addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.UNRELATED)
            .addComponent(jButton4)
            .addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.UNRELATED)
            .addComponent(jButton3)
            .addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.UNRELATED)
            .addComponent(jButton2)
            .addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.UNRELATED)
            .addComponent(jButton1)
            .addContainerGap(javax.swing.GroupLayout.DEFAULT_SIZE, Short.MAX_VALUE))
    );

    jButton5.getAccessibleContext().setAccessibleParent(this);

    add(jPanel1, new java.awt.GridBagConstraints());
    //jButton1.requestFocusInWindow();
    //NewJFrame.getRootPane().setDefaultButton(jButton1);
    //jButton1.requestFocus();
}// </editor-fold>





private void jButton1MouseClicked(java.awt.event.MouseEvent evt) {                                      
    // TODO add your handling code here:
    jPanel1.setVisible(false);
    NewJFrame.container.remove(NewJPanel1.this);
    NewJPanel p=new NewJPanel();
    NewJFrame.container.add(p);
}                                     

private void jPanel1KeyPressed(java.awt.event.KeyEvent evt) {                                   
    // TODO add your handling code here:

    System.out.println("Key Pressed");

}                                  

private void jButton5KeyPressed(java.awt.event.KeyEvent evt) {                                    
    // TODO add your handling code here:
    int key=evt.getKeyCode();
    if(key==KeyEvent.VK_ESCAPE)
    {
        System.out.println("Escape Pressed");
        jPanel1.setVisible(false);
            NewJFrame.container.remove(NewJPanel1.this);
            NewJPanel p=new NewJPanel();
            NewJFrame.container.add(p);
    }
}                                   

private void jButton4KeyPressed(java.awt.event.KeyEvent evt) {                                    
    // TODO add your handling code here:
    int key=evt.getKeyCode();
    if(key==KeyEvent.VK_ESCAPE)
    {
        System.out.println("Escape Pressed");
        jPanel1.setVisible(false);
            NewJFrame.container.remove(NewJPanel1.this);
            NewJPanel p=new NewJPanel();
            NewJFrame.container.add(p);
    }
}                                   

private void jButton3KeyPressed(java.awt.event.KeyEvent evt) {                                    
    // TODO add your handling code here:
    int key=evt.getKeyCode();
    if(key==KeyEvent.VK_ESCAPE)
    {
        System.out.println("Escape Pressed");
        jPanel1.setVisible(false);
            NewJFrame.container.remove(NewJPanel1.this);
            NewJPanel p=new NewJPanel();
            NewJFrame.container.add(p);
    }
}                                   

private void jButton2KeyPressed(java.awt.event.KeyEvent evt) {                                    
    // TODO add your handling code here:
    int key=evt.getKeyCode();
    if(key==KeyEvent.VK_ESCAPE)
    {
        System.out.println("Escape Pressed");
        jPanel1.setVisible(false);
            NewJFrame.container.remove(NewJPanel1.this);
            NewJPanel p=new NewJPanel();
            NewJFrame.container.add(p);
    }
}                                   

private void jButton1KeyPressed(java.awt.event.KeyEvent evt) {                                    
    // TODO add your handling code here:
    int key=evt.getKeyCode();
    if(key==KeyEvent.VK_ESCAPE||key==KeyEvent.VK_ENTER)
    {
            jPanel1.setVisible(false);
            NewJFrame.container.remove(NewJPanel1.this);
            NewJPanel p=new NewJPanel();
            NewJFrame.container.add(p);
    }
}                                   

private void jButton1MouseEntered(java.awt.event.MouseEvent evt) {                                      
    // TODO add your handling code here:

}                                     

private void formKeyPressed(java.awt.event.KeyEvent evt) {                                
    // TODO add your handling code here:
    System.out.println("key pressed");
}                               

private void jPanel1KeyReleased(java.awt.event.KeyEvent evt) {                                    
    // TODO add your handling code here:
}                                   

private void jButton5ActionPerformed(java.awt.event.ActionEvent evt) {                                         
    // TODO add your handling code here:
}                                        


// Variables declaration - do not modify
private javax.swing.JButton jButton1;
private javax.swing.JButton jButton2;
private javax.swing.JButton jButton3;
private javax.swing.JButton jButton4;
private javax.swing.JButton jButton5;
public static javax.swing.JPanel jPanel1;
// End of variables declaration

}

The Reason to make the button focus able is to traverse between the buttons with arrow keys or the keyboard.

Answer 1

To auto-focus a JButton (or any Component) on JPanel when its parent Component(JFrame in your case) is loaded (no matter on which location and when it is added to its parent component) you need to create your own panel which will be extending JPanel where you add component listener to receive component events from the panel. And finally, override the componentMoved and componentShow methods of java.awt.event.ComponentListener interface where set the default focused component as the button which you want (using button.requestFocus()). Here is the code I have provided for Demo. I hope this will help you to achieve the result that you are looking for:

import java.awt.AWTKeyStroke;
import java.awt.Container;
import java.awt.GridLayout;
import java.awt.BorderLayout;
import java.awt.KeyboardFocusManager;
import java.awt.event.ActionListener;
import java.awt.event.ActionEvent;
import java.awt.event.ComponentListener;
import java.awt.event.ComponentEvent;
import java.awt.event.KeyEvent;
import java.util.Set;
import java.util.HashSet;
import javax.swing.JPanel;
import javax.swing.JFrame;
import javax.swing.JButton;
import javax.swing.JOptionPane;
import javax.swing.KeyStroke;
import javax.swing.SwingUtilities;

public class FocusFrame extends JFrame
{
    JButton lowerButton;
    JButton upperButton;
    JPanel centerPanel;

    public void prepareAndShowGUI()
    {
        centerPanel = new FocusPanel();
        lowerButton = new JButton("Lower Button");
        upperButton = new JButton("Click here to hide/show center Panel");
        Container container = getContentPane();
        container.add(centerPanel,BorderLayout.CENTER);
        container.add(lowerButton,BorderLayout.SOUTH);
        container.add(upperButton,BorderLayout.NORTH);
        upperButton.addActionListener(new ActionListener()
        {
            public void actionPerformed(ActionEvent evt)
            {
                centerPanel.setVisible(!centerPanel.isVisible());
            }
        });
        pack();
        setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        setVisible(true);
    }
    public static void main(String[] st)
    {
        SwingUtilities.invokeLater( new Runnable()
        {
            @Override
            public void run()
            {
                FocusFrame fFrame = new FocusFrame();
                fFrame.prepareAndShowGUI();
            }
        });
    }
}

class FocusPanel extends JPanel implements ComponentListener
{
    int SIZE = 10;
    JButton[] buttons;
    public FocusPanel()
    {
        createAndAttachGUI();
    }
    private void createAndAttachGUI()
    {
        buttons = new JButton[SIZE];
        setLayout(new GridLayout(5,5));
        for (int i = 0 ; i < SIZE ; i++ )
        {
            buttons[i] = new JButton("Button " + (i+1));
            buttons[i].setFocusTraversalKeysEnabled(true);
            add(buttons[i]);
        }
        //For Forward Focus Traversal
        Set<AWTKeyStroke> set = new HashSet<AWTKeyStroke>(this.getFocusTraversalKeys(KeyboardFocusManager.FORWARD_TRAVERSAL_KEYS));
        set.add(KeyStroke.getKeyStroke(KeyEvent.VK_RIGHT,0));
        setFocusTraversalKeys(KeyboardFocusManager.FORWARD_TRAVERSAL_KEYS,set);
        //For Backward Focus Traversal
        set = new HashSet<AWTKeyStroke>(this.getFocusTraversalKeys(KeyboardFocusManager.BACKWARD_TRAVERSAL_KEYS));
        set.add(KeyStroke.getKeyStroke(KeyEvent.VK_LEFT,0));
        setFocusTraversalKeys(KeyboardFocusManager.BACKWARD_TRAVERSAL_KEYS,set);
        addComponentListener(this);
    }
    @Override
    public void componentHidden(ComponentEvent e)
    {}
    @Override
    public void componentMoved(ComponentEvent e)
    {
        buttons[0].requestFocus();
    }
    @Override
    public void componentResized(ComponentEvent e)
    {}
    @Override
    public void componentShown(ComponentEvent e)
    {
        buttons[0].requestFocus();
    }
}

Answer 2

If you change this:

public NewJPanel1() {
    initComponents();
}

to this:

public NewJPanel1() {
    initComponents();
    addComponentListener(new ComponentListener() {

        @Override
        public void componentResized(ComponentEvent ce) {}

        @Override
        public void componentMoved(ComponentEvent ce) {}

        @Override
        public void componentShown(ComponentEvent ce) {
            jButton1.requestFocus();
        }

        @Override
        public void componentHidden(ComponentEvent ce) {}
    });
}

Then it will work because that is always run when it is made visible. It is not visible until you add it to the NewJFrame.

Answer 3

The method

jButton1.requestFocus();

should work just fine. But it is essential when you're calling this method.

The method must be called after the button has been displayed. That means, don't call the requestFocus() in the constructor, instead call it when the panel is already visible.

Here is some pseudo code:

public NewJFrame() {
    initComponents();
    //some methods ommitted
    setVisible(true);

    //change to NewJPanel1

    //request focus after displaying the NewJPanel1
}

EDIT: Here is a concrete implementation of a possible solution.

NewPanel.java

private void jButton2ActionPerformed(java.awt.event.ActionEvent evt) {
    // TODO add your handling code here:
    jPanel1.setVisible(false);
    NewJFrame.container.remove(NewJPanel.this);
    NewJPanel1 p=new NewJPanel1();
    NewJFrame.container.add(p);

    p.initFocus();
}

NewJPanel1.java

public void initFocus() {
    jButton5.requestFocus();
}

Answer 4

Try this out:

public NewJFrame() {
    initComponents();
    rootPane= getRootPane();
    container=getContentPane();
    setSize(Toolkit.getDefaultToolkit().getScreenSize());
    setVisible(true);

    //added code:
    JButton jbutton5 = //get from NewJPanel1
    getRootPane().setDefaultButton(jbutton5);
    jbutton5.requestFocus();
}

You would need to create a method in NewJPanel1 to pass reference of jbutton5 to NewJFrame.

public JButton getDefaultButton () {
    return jButton5;
}