Tab keyboard to move from one textarea to another textarea ?

[Lando Chan]

Hello, as the subject states, it is about how to make the tab in our keyboard take the focus from one textarea to the next textarea.
I have found some code across the Internet, although it does not work because there is no clsTabOrder class in my function.
This is the code

Vector vector=new Vector(3);
vector.Add(textBox1);
vector.Add(textBox2);
vector.Add(textBox3);
clsTabOrder newPolicy=new clsTabOrder(vector);
setFocusTraversalPolicy(newPolicy);
textBox1.requestFocus();

Maybe somebody could tell me what is this clsTabOrder, or have another alternative for this problem.
Thank You.

[Campbell Ritchie]

Moving to the GUIs forum.

Please write yourself an SSCCE, so you can simply try out focus with the tab key. I shall try one for myself; please watch this space.

[Lando Chan]

I dont quite understand why you give me sscce. I guess my description is unclear so let me describe it one more.

It is not exactly a problem.
Just imagine you want to login your facebook account, first you insert the email textfield and press tab button to move to the password textfield. I want to know if I can apply that to my program.

For your information, I have two JTextArea and I want that when I press tab it moves to the next JTextArea

Thanks

[Campbell Ritchie]

Please go to the Java™ Tutorials and use ctrl‑;f‑Éc;focus”. I got two hits, which I think will be useful to you.

I couildn't get my SSCCE to work; I am sure somebody else will know more than me.

[Lando Chan]

I found out a useful site which explains about this focus
From reading this "Tab shifts the focus in the forward direction. Shift-Tab moves the focus in the backward direction. For example, in FocusConceptsDemo, the first button has the initial focus. Tabbing moves the focus through the buttons into the text area. Additional tabbing moves the cursor within the text area but not out of the text area because, inside a text area, Tab is not a focus traversal key. However, Control-Tab moves the focus out of the text area and into the first text field. Likewise, Control-Shift-Tab moves the focus out of the text area and into the previous component. The Control key is used by convention to move the focus out of any component that treats Tab in a special way, such as JTable."

I got the feeling that it is not possible to solve my problem

[Rob Camick]

Here are 4 approaches:

/*
    This is my understanding of how tabbing works. The focus manager
    recognizes the following default KeyStrokes for tabbing:

    forwards:  TAB or Ctrl-TAB
    backwards: Shift-TAB or Ctrl-Shift-TAB

    In the case of JTextArea, TAB and Shift-TAB have been removed from
    the defaults which means the KeyStroke is passed to the text area.
    The TAB KeyStroke inserts a tab into the Document. Shift-TAB seems
    to be ignored.

    This example shows different approaches for tabbing out of a JTextArea
*/
import java.awt.*;
import java.util.*;
import java.awt.event.*;
import javax.swing.*;

public class TextAreaTab extends JPanel
{
    public TextAreaTab()
    {
        setLayout(new BoxLayout(this, BoxLayout.Y_AXIS));

        add( nullTraversalKeys() );
        add( writeYourOwnAction() );
        add( useKeyListener() );
        add( addTraversalKeys() );
    }

    //  Reset the text area to use the default tab keys.
    //  This is probably the best solution.

    private JComponent nullTraversalKeys()
    {
        JTextArea textArea = new JTextArea(3, 30);

        textArea.setText("Null Traversal Keys\n2\n3\n4\n5\n6\n7\n8\n9");
        JScrollPane scrollPane = new JScrollPane( textArea );

        textArea.setFocusTraversalKeys(KeyboardFocusManager.FORWARD_TRAVERSAL_KEYS, null);
        textArea.setFocusTraversalKeys(KeyboardFocusManager.BACKWARD_TRAVERSAL_KEYS, null);

        return scrollPane;
    }

    //  Replace the Tab Actions. A little more complicated but this shows
    //  how to create a custom Action so you have full control.

    private JComponent writeYourOwnAction()
    {
        JTextArea textArea = new JTextArea(3, 30);
        textArea.setText("Write Your Own Tab Actions\n2\n3\n4\n5\n6\n7\n8\n9");
        JScrollPane scrollPane = new JScrollPane( textArea );

        InputMap im = textArea.getInputMap();
        KeyStroke tab = KeyStroke.getKeyStroke("TAB");
        textArea.getActionMap().put(im.get(tab), new TabAction(true));
        KeyStroke shiftTab = KeyStroke.getKeyStroke("shift TAB");
        im.put(shiftTab, shiftTab);
        textArea.getActionMap().put(im.get(shiftTab), new TabAction(false));

        return scrollPane;
    }

    //  Use a KeyListener
    //  (not recommended, since Swing provides newer and better API's)

    private JComponent useKeyListener()
    {
        JTextArea textArea = new JTextArea(3, 30);
        textArea.setText("Use Key Listener\n2\n3\n4\n5\n6\n7\n8\n9");
        JScrollPane scrollPane = new JScrollPane( textArea );

        textArea.addKeyListener(new KeyAdapter()
        {
            public void keyPressed(KeyEvent e)
            {
                if (e.getKeyCode() == KeyEvent.VK_TAB)
                {
                    e.consume();
                    KeyboardFocusManager.getCurrentKeyboardFocusManager().focusNextComponent();
                }

                if (e.getKeyCode() == KeyEvent.VK_TAB
                &&  e.isShiftDown())
                {
                    e.consume();
                    KeyboardFocusManager.getCurrentKeyboardFocusManager().focusPreviousComponent();
                }
            }
        });

        return scrollPane;
    }

    //  Add Tab and Shift-Tab KeyStrokes back as focus traversal keys.
    //  Seems more complicated then just using null, but at least
    //  it shows how to add a KeyStroke as a focus traversal key.

    private JComponent addTraversalKeys()
    {
        JTextArea textArea = new JTextArea(3, 30);
        textArea.setText("Add Traversal Keys\n2\n3\n4\n5\n6\n7\n8\n9");
        JScrollPane scrollPane = new JScrollPane( textArea );

        Set set = new HashSet( textArea.getFocusTraversalKeys(
            KeyboardFocusManager.FORWARD_TRAVERSAL_KEYS ) );
        set.add( KeyStroke.getKeyStroke( "TAB" ) );
        textArea.setFocusTraversalKeys(
            KeyboardFocusManager.FORWARD_TRAVERSAL_KEYS, set );

        set = new HashSet( textArea.getFocusTraversalKeys(
            KeyboardFocusManager.BACKWARD_TRAVERSAL_KEYS ) );
        set.add( KeyStroke.getKeyStroke( "shift TAB" ) );
        textArea.setFocusTraversalKeys(
            KeyboardFocusManager.BACKWARD_TRAVERSAL_KEYS, set );

        return scrollPane;
    }

    class TabAction extends AbstractAction
    {
        private boolean forward;

        public TabAction(boolean forward)
        {
            this.forward = forward;
        }

        public void actionPerformed(ActionEvent e)
        {
            if (forward)
                tabForward();
            else
                tabBackward();
        }

        private void tabForward()
        {
            KeyboardFocusManager manager = KeyboardFocusManager.getCurrentKeyboardFocusManager();
            manager.focusNextComponent();
        }

        private void tabBackward()
        {
            KeyboardFocusManager manager = KeyboardFocusManager.getCurrentKeyboardFocusManager();
            manager.focusPreviousComponent();
        }
    }

	private static void createAndShowGUI()
	{
		JFrame frame = new JFrame("Textare Tabbing");
		frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
		frame.add(new TextAreaTab());
		frame.pack();
		frame.setLocationByPlatform( true );
		frame.setVisible( true );
	}

	public static void main(String[] args) throws Exception
	{
		EventQueue.invokeLater( () -> createAndShowGUI() );
/*
		EventQueue.invokeLater(new Runnable()
		{
			public void run()
			{
				createAndShowGUI();
			}
		});
*/
	}
}

[Lando Chan]

Thanks a lot, it is a great explanation.