001    /* ========================================================================
002     * JCommon : a free general purpose class library for the Java(tm) platform
003     * ========================================================================
004     *
005     * (C) Copyright 2000-2005, by Object Refinery Limited and Contributors.
006     * 
007     * Project Info:  http://www.jfree.org/jcommon/index.html
008     *
009     * This library is free software; you can redistribute it and/or modify it 
010     * under the terms of the GNU Lesser General Public License as published by 
011     * the Free Software Foundation; either version 2.1 of the License, or 
012     * (at your option) any later version.
013     *
014     * This library is distributed in the hope that it will be useful, but 
015     * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY 
016     * or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public 
017     * License for more details.
018     *
019     * You should have received a copy of the GNU Lesser General Public
020     * License along with this library; if not, write to the Free Software
021     * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, 
022     * USA.  
023     *
024     * [Java is a trademark or registered trademark of Sun Microsystems, Inc. 
025     * in the United States and other countries.]
026     * 
027     * ---------------
028     * ArrowPanel.java
029     * ---------------
030     * (C) Copyright 2002-2004, by Object Refinery Limited.
031     *
032     * Original Author:  David Gilbert (for Object Refinery Limited);
033     * Contributor(s):   -;
034     *
035     * $Id: ArrowPanel.java,v 1.5 2005/11/16 15:58:41 taqua Exp $
036     *
037     * Changes
038     * -------
039     * 25-Sep-2002 : Version 1 (DG);
040     * 13-Oct-2002 : Added Javadocs (DG);
041     *
042     */
043    
044    package org.jfree.ui;
045    
046    import java.awt.Dimension;
047    import java.awt.Graphics;
048    import java.awt.Graphics2D;
049    import java.awt.Insets;
050    import java.awt.Polygon;
051    import java.awt.Shape;
052    import java.awt.geom.Rectangle2D;
053    
054    import javax.swing.JPanel;
055    
056    /**
057     * A basic panel that displays a small up or down arrow.
058     *
059     * @author David Gilbert
060     */
061    public class ArrowPanel extends JPanel {
062    
063        /** A constant for the up arrow. */
064        public static final int UP = 0;
065    
066        /** A constant for the down arrow. */
067        public static final int DOWN = 1;
068    
069        /** The arrow type. */
070        private int type = UP;
071    
072        /** The available area. */
073        private Rectangle2D available = new Rectangle2D.Float();
074    
075        /**
076         * Creates a new arrow panel.
077         *
078         * @param type  the arrow type.
079         */
080        public ArrowPanel(final int type) {
081            this.type = type;
082            setPreferredSize(new Dimension(14, 9));
083        }
084    
085        /**
086         * Paints the arrow panel.
087         *
088         * @param g  the graphics device for drawing on.
089         */
090        public void paintComponent(final Graphics g) {
091    
092            super.paintComponent(g);
093            final Graphics2D g2 = (Graphics2D) g;
094    
095            // first determine the size of the drawing area...
096            final Dimension size = getSize();
097            final Insets insets = getInsets();
098            this.available.setRect(insets.left, insets.top,
099                                   size.getWidth() - insets.left - insets.right,
100                                   size.getHeight() - insets.top - insets.bottom);
101            g2.translate(insets.left, insets.top);
102            g2.fill(getArrow(this.type));
103    
104        }
105    
106        /**
107         * Returns a shape for the arrow.
108         *
109         * @param t  the arrow type.
110         *
111         * @return the arrow shape.
112         */
113        private Shape getArrow(final int t) {
114            switch (t) {
115                case UP : return getUpArrow();
116                case DOWN : return getDownArrow();
117                default : return getUpArrow();
118            }
119        }
120    
121        /**
122         * Returns an up arrow.
123         *
124         * @return an up arrow.
125         */
126        private Shape getUpArrow() {
127            final Polygon result = new Polygon();
128            result.addPoint(7, 2);
129            result.addPoint(2, 7);
130            result.addPoint(12, 7);
131            return result;
132        }
133    
134        /**
135         * Returns a down arrow.
136         *
137         * @return a down arrow.
138         */
139        private Shape getDownArrow() {
140            final Polygon result = new Polygon();
141            result.addPoint(7, 7);
142            result.addPoint(2, 2);
143            result.addPoint(12, 2);
144            return result;
145        }
146    
147    }