praktikum-holons/src/ui/view/component/ButtonTabComponent.java

package ui.view.component;

/*
 * Copyright (c) 1995, 2008, Oracle and/or its affiliates. All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 *   - Redistributions of source code must retain the above copyright
 *     notice, this list of conditions and the following disclaimer.
 *
 *   - Redistributions in binary form must reproduce the above copyright
 *     notice, this list of conditions and the following disclaimer in the
 *     documentation and/or other materials provided with the distribution.
 *
 *   - Neither the name of Oracle or the names of its
 *     contributors may be used to endorse or promote products derived
 *     from this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS
 * IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
 * THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
 * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE COPYRIGHT OWNER OR
 * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
 * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
 * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
 * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
 * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */

import javax.swing.*;
import javax.swing.plaf.basic.BasicButtonUI;
import java.awt.*;
import java.awt.event.*;

/**
 * Component to be used as tabComponent; Contains a JLabel to show the text and
 * a JButton to close the tab it belongs to
 */
public class ButtonTabComponent extends JPanel {
	private final JTabbedPane pane;

	public ButtonTabComponent(final JTabbedPane pane) {
		// unset default FlowLayout' gaps
		super(new FlowLayout(FlowLayout.LEFT, 0, 0));
		if (pane == null) {
			throw new NullPointerException("TabbedPane is null");
		}
		this.pane = pane;
		setOpaque(false);

		// make JLabel read titles from JTabbedPane
		JLabel label = new JLabel() {
			public String getText() {
				int i = pane.indexOfTabComponent(ButtonTabComponent.this);
				if (i != -1) {
					return pane.getTitleAt(i);
				}
				return null;
			}
		};

		add(label);
		// add more space between the label and the button
		label.setBorder(BorderFactory.createEmptyBorder(0, 0, 0, 5));
		// tab button
		JButton button = new TabButton();
		add(button);
		// add more space to the top of the component
		setBorder(BorderFactory.createEmptyBorder(2, 0, 0, 0));
	}

	private class TabButton extends JButton implements ActionListener {
		public TabButton() {
			int size = 17;
			setPreferredSize(new Dimension(size, size));
			setToolTipText("close this tab");
			// Make the button looks the same for all Laf's
			setUI(new BasicButtonUI());
			// Make it transparent
			setContentAreaFilled(false);
			// No need to be focusable
			setFocusable(false);
			setBorder(BorderFactory.createEtchedBorder());
			setBorderPainted(false);
			// Making nice rollover effect
			// we use the same listener for all buttons
			addMouseListener(buttonMouseListener);
			setRolloverEnabled(true);
			// Close the proper tab by clicking the button
			addActionListener(this);
		}

		public void actionPerformed(ActionEvent e) {
			removeTabs();
		}

		// we don't want to update UI for this button
		public void updateUI() {
		}

		// paint the cross
		protected void paintComponent(Graphics g) {
			super.paintComponent(g);
			Graphics2D g2 = (Graphics2D) g.create();
			// shift the image for pressed buttons
			if (getModel().isPressed()) {
				g2.translate(1, 1);
			}
			g2.setStroke(new BasicStroke(2));
			g2.setColor(Color.BLACK);
			if (getModel().isRollover()) {
				g2.setColor(Color.MAGENTA);
			}
			int delta = 6;
			g2.drawLine(delta, delta, getWidth() - delta - 1, getHeight() - delta - 1);
			g2.drawLine(getWidth() - delta - 1, delta, delta, getHeight() - delta - 1);
			g2.dispose();
		}
	}

	private final static MouseListener buttonMouseListener = new MouseAdapter() {
		public void mouseEntered(MouseEvent e) {
			Component component = e.getComponent();
			if (component instanceof AbstractButton button) {
				button.setBorderPainted(true);
			}
		}

		public void mouseExited(MouseEvent e) {
			Component component = e.getComponent();
			if (component instanceof AbstractButton button) {
				button.setBorderPainted(false);
			}
		}
	};
	
	/**
	 * removes both Tabs 
	 */
	public void removeTabs() {
		int i = pane.indexOfTabComponent(ButtonTabComponent.this);
		if (i != -1) {
			pane.remove(i);
		}
	}
}