ColorComboBoxEditor.java Source code

Introduction

Here is the source code for ColorComboBoxEditor.java

Source

import java.awt.BorderLayout;
import java.awt.Color;
import java.awt.Component;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;

import javax.swing.ComboBoxEditor;
import javax.swing.JButton;
import javax.swing.JColorChooser;
import javax.swing.JComboBox;
import javax.swing.JFrame;
import javax.swing.event.EventListenerList;

class ColorComboBoxEditor implements ComboBoxEditor {
    final protected JButton editor;

    protected EventListenerList listenerList = new EventListenerList();

    public ColorComboBoxEditor(Color initialColor) {
        editor = new JButton("");
        editor.setBackground(initialColor);
        ActionListener actionListener = new ActionListener() {
            public void actionPerformed(ActionEvent e) {
                Color currentBackground = editor.getBackground();
                Color color = JColorChooser.showDialog(editor, "Color Chooser", currentBackground);
                if ((color != null) && (currentBackground != color)) {
                    editor.setBackground(color);
                    fireActionEvent(color);
                }
            }
        };
        editor.addActionListener(actionListener);
    }

    public void addActionListener(ActionListener l) {
        listenerList.add(ActionListener.class, l);
    }

    public Component getEditorComponent() {
        return editor;
    }

    public Object getItem() {
        return editor.getBackground();
    }

    public void removeActionListener(ActionListener l) {
        listenerList.remove(ActionListener.class, l);
    }

    public void selectAll() {
        // Ignore
    }

    public void setItem(Object newValue) {
        if (newValue instanceof Color) {
            Color color = (Color) newValue;
            editor.setBackground(color);
        } else {
            try {
                Color color = Color.decode(newValue.toString());
                editor.setBackground(color);
            } catch (NumberFormatException e) {
            }
        }
    }

    protected void fireActionEvent(Color color) {
        Object listeners[] = listenerList.getListenerList();
        for (int i = listeners.length - 2; i >= 0; i -= 2) {
            if (listeners[i] == ActionListener.class) {
                ActionEvent actionEvent = new ActionEvent(editor, ActionEvent.ACTION_PERFORMED, color.toString());
                ((ActionListener) listeners[i + 1]).actionPerformed(actionEvent);
            }
        }
    }
}

public class Main {
    public static void main(String args[]) {
        Color colors[] = { Color.RED, Color.BLUE, Color.BLACK, Color.WHITE };
        JFrame frame = new JFrame("Editable JComboBox");
        frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);

        final JComboBox comboBox = new JComboBox(colors);
        comboBox.setEditable(true);
        comboBox.setEditor(new ColorComboBoxEditor(Color.RED));
        frame.add(comboBox, BorderLayout.NORTH);

        frame.setSize(300, 200);
        frame.setVisible(true);
    }
}