CloseableTabs.java

package org.ggp.base.util.ui;

import java.awt.Color;
import java.awt.Graphics;
import java.awt.GridBagConstraints;
import java.awt.GridBagLayout;
import java.awt.Insets;
import java.awt.image.BufferedImage;

import javax.swing.AbstractAction;
import javax.swing.ImageIcon;
import javax.swing.JButton;
import javax.swing.JComponent;
import javax.swing.JLabel;
import javax.swing.JPanel;
import javax.swing.JTabbedPane;

public class CloseableTabs {
    private static final int CLOSE_ICON_SIZE = 8;

    public static void addClosableTab(JTabbedPane tabPane, JComponent tabContent, String tabName, AbstractAction closeAction) {
        JPanel tabTopPanel = new JPanel(new GridBagLayout());
        tabTopPanel.setOpaque(false);

        JButton btnClose = new JButton();
        BufferedImage img = new BufferedImage(CLOSE_ICON_SIZE, CLOSE_ICON_SIZE, BufferedImage.TYPE_4BYTE_ABGR);
        Graphics g = img.getGraphics();
        g.setColor(Color.BLACK);
        g.drawLine(0, CLOSE_ICON_SIZE-1, CLOSE_ICON_SIZE-1, 0);
        g.drawLine(0, 0, CLOSE_ICON_SIZE-1, CLOSE_ICON_SIZE-1);
        btnClose.setIcon(new ImageIcon(img));
        btnClose.addActionListener(closeAction);

        tabTopPanel.add(new JLabel(tabName), new GridBagConstraints(0, 0, 1, 1, 1.0, 1.0, GridBagConstraints.CENTER, GridBagConstraints.BOTH, new Insets(0, 0, 0, 0), 0, 0));
        tabTopPanel.add(btnClose, new GridBagConstraints(1, 0, 1, 1, 1.0, 1.0, GridBagConstraints.CENTER, GridBagConstraints.BOTH, new Insets(0, 4, 0, 0), 0, 0));

        tabPane.addTab(tabName, tabContent);
        tabPane.setTabComponentAt(tabPane.getTabCount()-1, tabTopPanel);
    }
}