Java JTextField with input hint

Question

I would like to add a hint value to my JTextField. It should look like Firefox rendering of <input type="text" title="bla">. This creates a edit field with the text 'bla' in the background. If the textbox has focus the title-text disappeares and just reappears if the user leaves the editbox without text.

Is there a (free) swing component that does something like this?

Answer 1

For any Swing component (that is, anything that extends JComponent), you can call the setToolTipText(String) method.

For more information, reference the following links:

• API Documentation for setToolTipText
• "How to Use Tool Tips" tutorial

Answer 2

Take a look at this one: http://code.google.com/p/xswingx/

It is not very difficult to implement it by yourself, btw. A couple of listeners and custom renderer and voila.

Answer 3

You could create your own:

import java.awt.BorderLayout;
import java.awt.event.FocusEvent;
import java.awt.event.FocusListener;
import javax.swing.*;

public class Main {   
    public static void main(String[] args) {
        JFrame frame = new JFrame();
        frame.setLayout(new BorderLayout());
        frame.add(new HintTextField("A hint here..."), BorderLayout.NORTH);
        frame.add(new HintTextField("Another hint here..."), BorderLayout.SOUTH);
        frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        frame.setVisible(true);
        frame.pack();
    }
}

class HintTextField extends JTextField implements FocusListener {

    private final String hint;

    public HintTextField(final String hint) {
        super(hint);
        this.hint = hint;
        super.addFocusListener(this);
    }

    @Override
    public void focusGained(FocusEvent e) {
        if(this.getText().isEmpty()) {
            super.setText("");
        }
    }
    @Override
    public void focusLost(FocusEvent e) {
        if(this.getText().isEmpty()) {
            super.setText(hint);
        }
    }

    @Override
    public String getText() {
        String typed = super.getText();
        return typed.equals(hint) ? "" : typed;
    }
}

If you're still on Java 1.5, replace the this.getText().isEmpty() with this.getText().length() == 0.