001    /* ========================================================================
002     * JCommon : a free general purpose class library for the Java(tm) platform
003     * ========================================================================
004     *
005     * (C) Copyright 2000-2009, 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     * StrokeSample.java
029     * -----------------
030     * (C) Copyright 2000-2009, by Object Refinery Limited.
031     *
032     * Original Author:  David Gilbert (for Object Refinery Limited);
033     * Contributor(s):   -;
034     *
035     * $Id: StrokeSample.java,v 1.5 2009/02/27 13:58:41 mungady Exp $
036     *
037     * Changes (from 26-Oct-2001)
038     * --------------------------
039     * 26-Oct-2001 : Changed package to com.jrefinery.ui.*;
040     * 14-Oct-2002 : Fixed errors reported by Checkstyle (DG);
041     * 21-Mar-2003 : Fixed null pointer exception, bug 705126 (DG);
042     *
043     */
044    
045    package org.jfree.ui;
046    
047    import java.awt.Component;
048    import java.awt.Dimension;
049    import java.awt.Graphics;
050    import java.awt.Graphics2D;
051    import java.awt.Insets;
052    import java.awt.RenderingHints;
053    import java.awt.Stroke;
054    import java.awt.geom.Ellipse2D;
055    import java.awt.geom.Line2D;
056    import java.awt.geom.Point2D;
057    import javax.swing.JComponent;
058    import javax.swing.JList;
059    import javax.swing.ListCellRenderer;
060    
061    /**
062     * A panel that displays a stroke sample.
063     *
064     * @author David Gilbert
065     */
066    public class StrokeSample extends JComponent implements ListCellRenderer {
067    
068        /** The stroke being displayed (may be null). */
069        private Stroke stroke;
070    
071        /** The preferred size of the component. */
072        private Dimension preferredSize;
073    
074        /**
075         * Creates a StrokeSample for the specified stroke.
076         *
077         * @param stroke  the sample stroke (<code>null</code> permitted).
078         */
079        public StrokeSample(final Stroke stroke) {
080            this.stroke = stroke;
081            this.preferredSize = new Dimension(80, 18);
082            setPreferredSize(this.preferredSize);
083        }
084    
085        /**
086         * Returns the current Stroke object being displayed.
087         *
088         * @return The stroke (possibly <code>null</code>).
089         */
090        public Stroke getStroke() {
091            return this.stroke;
092        }
093    
094        /**
095         * Sets the stroke object being displayed and repaints the component.
096         *
097         * @param stroke  the stroke (<code>null</code> permitted).
098         */
099        public void setStroke(final Stroke stroke) {
100            this.stroke = stroke;
101            repaint();
102        }
103    
104        /**
105         * Returns the preferred size of the component.
106         *
107         * @return the preferred size of the component.
108         */
109        public Dimension getPreferredSize() {
110            return this.preferredSize;
111        }
112    
113        /**
114         * Draws a line using the sample stroke.
115         *
116         * @param g  the graphics device.
117         */
118        public void paintComponent(final Graphics g) {
119    
120            final Graphics2D g2 = (Graphics2D) g;
121            g2.setRenderingHint(RenderingHints.KEY_ANTIALIASING,
122                    RenderingHints.VALUE_ANTIALIAS_ON);
123            final Dimension size = getSize();
124            final Insets insets = getInsets();
125            final double xx = insets.left;
126            final double yy = insets.top;
127            final double ww = size.getWidth() - insets.left - insets.right;
128            final double hh = size.getHeight() - insets.top - insets.bottom;
129    
130            // calculate point one
131            final Point2D one =  new Point2D.Double(xx + 6, yy + hh / 2);
132            // calculate point two
133            final Point2D two =  new Point2D.Double(xx + ww - 6, yy + hh / 2);
134            // draw a circle at point one
135            final Ellipse2D circle1 = new Ellipse2D.Double(one.getX() - 5,
136                    one.getY() - 5, 10, 10);
137            final Ellipse2D circle2 = new Ellipse2D.Double(two.getX() - 6,
138                    two.getY() - 5, 10, 10);
139    
140            // draw a circle at point two
141            g2.draw(circle1);
142            g2.fill(circle1);
143            g2.draw(circle2);
144            g2.fill(circle2);
145    
146            // draw a line connecting the points
147            final Line2D line = new Line2D.Double(one, two);
148            if (this.stroke != null) {
149                g2.setStroke(this.stroke);
150                g2.draw(line);
151            }
152    
153        }
154    
155        /**
156         * Returns a list cell renderer for the stroke, so the sample can be
157         * displayed in a list or combo.
158         *
159         * @param list  the list.
160         * @param value  the value.
161         * @param index  the index.
162         * @param isSelected  selected?
163         * @param cellHasFocus  focussed?
164         *
165         * @return the component for rendering.
166         */
167        public Component getListCellRendererComponent(JList list, Object value,
168                int index, boolean isSelected, boolean cellHasFocus) {
169            if (value instanceof Stroke) {
170                setStroke((Stroke) value);
171            }
172            else {
173                setStroke(null);
174            }
175            return this;
176        }
177    
178    }