JTextField resizing behaviour.

Question

I would like to know how to consistently configure a JTextField to have a fixed size no matter the container's layout, the look and feel, and the field content.
Here is an example :
import javax.swing.*;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
public class DemoDateField2 {
    private static int currentLookAndFeelId;
    public static void main(String[] args) {
        final JTextField fixedColumnsField = new JTextField("It has 10 columns", 10);
        final JTextField notFixedColumnsField = new JTextField("It has no fixed columns");
        JComboBox comboBox = new JComboBox();
        comboBox.setPrototypeDisplayValue("01 Jan 1970");
        comboBox.setEditable(true);
        comboBox.setModel(new DefaultComboBoxModel(new String[]{"01 Jan 1970", "02 Jan 1970", "03 Jan 1970"}));
        JButton clearFixedButton = new JButton("Clear Fixed");
        JButton clearNotFixedButton = new JButton("Clear NotFixed");
        JButton lafButton = new JButton("Look and feel");
        JPanel panel = new JPanel();
        panel.add(fixedColumnsField);
        panel.add(notFixedColumnsField);
        panel.add(comboBox);
        panel.add(clearFixedButton);
        panel.add(clearNotFixedButton);
        panel.add(lafButton);
        final JFrame frame = new JFrame();
        frame.getContentPane().add(panel);
        frame.setSize(640, 480);
        frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        frame.pack();
        frame.setVisible(true);
        clearFixedButton.addActionListener(new ActionListener() {
            public void actionPerformed(ActionEvent e) {
                fixedColumnsField.setText("");
        clearNotFixedButton.addActionListener(new ActionListener() {
            public void actionPerformed(ActionEvent e) {
                notFixedColumnsField.setText("");
        lafButton.addActionListener(new ActionListener() {
            public void actionPerformed(ActionEvent e) {
                UIManager.LookAndFeelInfo[] infos = UIManager.getInstalledLookAndFeels();
                if (currentLookAndFeelId == infos.length - 1) {
                    currentLookAndFeelId = 0;
                else {
                    currentLookAndFeelId++;
                try {
                    UIManager.setLookAndFeel(infos[currentLookAndFeelId].getClassName());
                catch (Exception e1) {
                SwingUtilities.updateComponentTreeUI(frame);
}In this example, the first text field (the fixed column one) has a bad behaviour when switching LAF (the text is clipped in Windows LAF).
The second field is ok when switching LAF, but if you clear it and resize the frame, its widht is near zero.
The combo box behaves perfectly in both situations : LAF and clear&resize...
To sum it up : is it possible to have the same behaviour with a JTextField as with a JComboBox and its prototype method ?

Answer 1

Hello Phil,
yes, there are always side effects when changing the L&F. I have no perfect solution, but when you add a
import java.awt.*;
notFixedColumnsField.setPreferredSize(new Dimension (140,20));at least the shrinking doesn't happen any more when the field is empty.
You may also declare the field's dimension in dependence of another field such as
notFixedColumnsField.setPreferredSize(fixedColumnsField.getPreferredSize());hth
J�rg