adding jtextfield automatically record from corresponding jtextfield value

Question

my question is when i insert the first name in jtextfield then corresponding last name of this record show automatically in another jtextfield?

it means i dont want insert same data again and again..once i insert the record in database the next time same record inserted automatically in next form

so anyone here to give me snippet? Thanks in advance

Answer 1

@MirroredFate (to comments in another answer here) never to use KeyListener, use DocumentListener, then there you can to determine all possible users inputs types inside JTextComponents

import java.awt.GridLayout;
import javax.swing.*;
import javax.swing.event.DocumentEvent;
import javax.swing.event.DocumentListener;

public class TextLabelMirror {

    private JPanel mainPanel = new JPanel();
    private JTextField field = new JTextField(20);
    private JTextField field1 = new JTextField(20);

    public TextLabelMirror() {
        field.getDocument().addDocumentListener(new DocumentListener() {

            @Override
            public void changedUpdate(DocumentEvent e) {
                updateLabel(e);
            }

            @Override
            public void insertUpdate(DocumentEvent e) {
                updateLabel(e);
            }

            @Override
            public void removeUpdate(DocumentEvent e) {
                updateLabel(e);
            }

            private void updateLabel(DocumentEvent e) {
                java.awt.EventQueue.invokeLater(new Runnable() {

                    @Override
                    public void run() {
                        field1.setText(field.getText());
                    }
                });
            }
        });

        mainPanel.setLayout(new GridLayout(1, 0, 10, 0));
        mainPanel.add(field);
        mainPanel.add(field1);
    }

    public JComponent getComponent() {
        return mainPanel;
    }

    private static void createAndShowUI() {
        JFrame frame = new JFrame("TextLabelMirror");
        frame.getContentPane().add(new TextLabelMirror().getComponent());
        frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        frame.pack();
        frame.setLocationRelativeTo(null);
        frame.setVisible(true);
    }

    public static void main(String[] args) {
        java.awt.EventQueue.invokeLater(new Runnable() {

            @Override
            public void run() {
                createAndShowUI();
            }
        });
    }
}

Answer 2

You really want to check out this documentation: http://docs.oracle.com/javase/tutorial/uiswing/events/keylistener.html

Your code will look something like this:

JTextField firstName = new JTextField();
JTextField lastName = new JTextField();
KeyListener kl = MyCustomKeyListener();
firstName.addKeyListener(kl);

In your custom KeyListener, override the keyTyped() method to find the value of firstName, look it up in the database to find the corresponding last name, then use it to set the value of lastName.

This way you can make it so that every time a key is typed this will execute, or you can check and make sure only a specific key triggers action (like pressing return).

Also, I should mention you can use an anonymous class for this. Instead of creating MyCustomKeyListener, you can say:

firstName.addKeyListener(new KeyListener(){
    void keyTyped(keyEvent e){
        //whatever you want to happen when the key is typed in here
    }
});

EDIT: As it has been pointed out, it may be better to use a DocumentListener. This is done by accessing the underlying JTextField's document and adding the listener to that, as shown in the answer here: Value Change Listener to JTextField