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Java > Open Source Codes > org > jfree > layout > RadialLayout


1 /* ========================================================================
2  * JCommon : a free general purpose class library for the Java(tm) platform
3  * ========================================================================
4  *
5  * (C) Copyright 2000-2005, by Object Refinery Limited and Contributors.
6  *
7  * Project Info: http://www.jfree.org/jcommon/index.html
8  *
9  * This library is free software; you can redistribute it and/or modify it
10  * under the terms of the GNU Lesser General Public License as published by
11  * the Free Software Foundation; either version 2.1 of the License, or
12  * (at your option) any later version.
13  *
14  * This library is distributed in the hope that it will be useful, but
15  * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
16  * or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public
17  * License for more details.
18  *
19  * You should have received a copy of the GNU Lesser General Public
20  * License along with this library; if not, write to the Free Software
21  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301,
22  * USA.
23  *
24  * [Java is a trademark or registered trademark of Sun Microsystems, Inc.
25  * in the United States and other countries.]
26  *
27  * -----------------
28  * RadialLayout.java
29  * -----------------
30  * (C) Copyright 2003, 2004, by Bryan Scott (for Australian Antarctic Division).
31  *
32  * Original Author: Bryan Scott (for Australian Antarctic Division);
33  * Contributor(s): David Gilbert (for Object Refinery Limited);
34  *
35  *
36  * Changes:
37  * --------
38  * 30-Jun-2003 : Version 1 (BS);
39  * 24-Jul-2003 : Completed missing Javadocs (DG);
40  *
41  */
42
43 package org.jfree.layout;
44
45 import java.awt.Checkbox JavaDoc;
46 import java.awt.Component JavaDoc;
47 import java.awt.Container JavaDoc;
48 import java.awt.Dimension JavaDoc;
49 import java.awt.Frame JavaDoc;
50 import java.awt.Insets JavaDoc;
51 import java.awt.LayoutManager JavaDoc;
52 import java.awt.Panel JavaDoc;
53 import java.io.Serializable JavaDoc;
54
55 /**
56  * RadialLayout is a component layout manager. Compents are laid out in a
57  * circle. If only one component is contained in the layout it is positioned
58  * centrally, otherwise components are evenly spaced around the centre with
59  * the first component placed to the North.
60  *<P>
61  * This code was developed to display CTD rosette firing control
62  *
63  * WARNING: Not thoughly tested, use at own risk.
64  *
65  * @author Bryan Scott (for Australian Antarctic Division)
66  */
67
68 public class RadialLayout implements LayoutManager JavaDoc, Serializable JavaDoc {
69     
70     /** For serialization. */
71     private static final long serialVersionUID = -7582156799248315534L;
72     
73     /** The minimum width. */
74     private int minWidth = 0;
75     
76     /** The minimum height. */
77     private int minHeight = 0;
78     
79     /** The maximum component width. */
80     private int maxCompWidth = 0;
81     
82     /** The maximum component height. */
83     private int maxCompHeight = 0;
84     
85     /** The preferred width. */
86     private int preferredWidth = 0;
87     
88     /** The preferred height. */
89     private int preferredHeight = 0;
90     
91     /** Size unknown flag. */
92     private boolean sizeUnknown = true;
93
94     /**
95      * Constructs this layout manager with default properties.
96      */
97     public RadialLayout() {
98         super();
99     }
100
101     /**
102      * Not used.
103      *
104      * @param comp the component.
105      */
106     public void addLayoutComponent(final Component JavaDoc comp) {
107         // not used
108 }
109
110     /**
111      * Not used.
112      *
113      * @param comp the component.
114      */
115     public void removeLayoutComponent(final Component JavaDoc comp) {
116         // not used
117 }
118
119     /**
120      * Not used.
121      *
122      * @param name the component name.
123      * @param comp the component.
124      */
125     public void addLayoutComponent(final String JavaDoc name, final Component JavaDoc comp) {
126         // not used
127 }
128
129     /**
130      * Not used.
131      *
132      * @param name the component name.
133      * @param comp the component.
134      */
135     public void removeLayoutComponent(final String JavaDoc name, final Component JavaDoc comp) {
136         // not used
137 }
138
139     /**
140      * Sets the sizes attribute of the RadialLayout object.
141      *
142      * @param parent the parent.
143      *
144      * @see LayoutManager
145      */
146     private void setSizes(final Container JavaDoc parent) {
147         final int nComps = parent.getComponentCount();
148         //Reset preferred/minimum width and height.
149 this.preferredWidth = 0;
150         this.preferredHeight = 0;
151         this.minWidth = 0;
152         this.minHeight = 0;
153         for (int i = 0; i < nComps; i++) {
154             final Component JavaDoc c = parent.getComponent(i);
155             if (c.isVisible()) {
156                 final Dimension JavaDoc d = c.getPreferredSize();
157                 if (this.maxCompWidth < d.width) {
158                     this.maxCompWidth = d.width;
159                 }
160                 if (this.maxCompHeight < d.height) {
161                     this.maxCompHeight = d.height;
162                 }
163                 this.preferredWidth += d.width;
164                 this.preferredHeight += d.height;
165             }
166         }
167         this.preferredWidth = this.preferredWidth / 2;
168         this.preferredHeight = this.preferredHeight / 2;
169         this.minWidth = this.preferredWidth;
170         this.minHeight = this.preferredHeight;
171     }
172
173     /**
174      * Returns the preferred size.
175      *
176      * @param parent the parent.
177      *
178      * @return The preferred size.
179      * @see LayoutManager
180      */
181     public Dimension JavaDoc preferredLayoutSize(final Container JavaDoc parent) {
182         final Dimension JavaDoc dim = new Dimension JavaDoc(0, 0);
183         setSizes(parent);
184
185         //Always add the container's insets!
186 final Insets JavaDoc insets = parent.getInsets();
187         dim.width = this.preferredWidth + insets.left + insets.right;
188         dim.height = this.preferredHeight + insets.top + insets.bottom;
189
190         this.sizeUnknown = false;
191         return dim;
192     }
193
194     /**
195      * Returns the minimum size.
196      *
197      * @param parent the parent.
198      *
199      * @return The minimum size.
200      * @see LayoutManager
201      */
202     public Dimension JavaDoc minimumLayoutSize(final Container JavaDoc parent) {
203         final Dimension JavaDoc dim = new Dimension JavaDoc(0, 0);
204
205         //Always add the container's insets!
206 final Insets JavaDoc insets = parent.getInsets();
207         dim.width = this.minWidth + insets.left + insets.right;
208         dim.height = this.minHeight + insets.top + insets.bottom;
209
210         this.sizeUnknown = false;
211         return dim;
212     }
213
214    /**
215     * This is called when the panel is first displayed, and every time its size
216     * changes.
217     * Note: You CAN'T assume preferredLayoutSize or minimumLayoutSize will be
218     * called -- in the case of applets, at least, they probably won't be.
219     *
220     * @param parent the parent.
221     * @see LayoutManager
222     */
223     public void layoutContainer(final Container JavaDoc parent) {
224         final Insets JavaDoc insets = parent.getInsets();
225         final int maxWidth = parent.getSize().width
226             - (insets.left + insets.right);
227         final int maxHeight = parent.getSize().height
228             - (insets.top + insets.bottom);
229         final int nComps = parent.getComponentCount();
230         int x = 0;
231         int y = 0;
232
233         // Go through the components' sizes, if neither preferredLayoutSize nor
234 // minimumLayoutSize has been called.
235 if (this.sizeUnknown) {
236             setSizes(parent);
237         }
238
239         if (nComps < 2) {
240             final Component JavaDoc c = parent.getComponent(0);
241             if (c.isVisible()) {
242                 final Dimension JavaDoc d = c.getPreferredSize();
243                 c.setBounds(x, y, d.width, d.height);
244             }
245         }
246         else {
247             double radialCurrent = Math.toRadians(90);
248             final double radialIncrement = 2 * Math.PI / nComps;
249             final int midX = maxWidth / 2;
250             final int midY = maxHeight / 2;
251             final int a = midX - this.maxCompWidth;
252             final int b = midY - this.maxCompHeight;
253             for (int i = 0; i < nComps; i++) {
254                 final Component JavaDoc c = parent.getComponent(i);
255                 if (c.isVisible()) {
256                     final Dimension JavaDoc d = c.getPreferredSize();
257                     x = (int) (midX
258                                - (a * Math.cos(radialCurrent))
259                                - (d.getWidth() / 2)
260                                + insets.left);
261                     y = (int) (midY
262                                - (b * Math.sin(radialCurrent))
263                                - (d.getHeight() / 2)
264                                + insets.top);
265
266                     // Set the component's size and position.
267 c.setBounds(x, y, d.width, d.height);
268                 }
269                 radialCurrent += radialIncrement;
270             }
271         }
272     }
273
274     /**
275      * Returns the class name.
276      *
277      * @return The class name.
278      */
279     public String JavaDoc toString() {
280         return getClass().getName();
281     }
282
283     /**
284      * Run a demonstration.
285      *
286      * @param args ignored.
287      *
288      * @throws Exception when an error occurs.
289      */
290     public static void main(final String JavaDoc[] args) throws Exception JavaDoc {
291         final Frame JavaDoc frame = new Frame JavaDoc();
292         final Panel JavaDoc panel = new Panel JavaDoc();
293         panel.setLayout(new RadialLayout());
294
295         panel.add(new Checkbox JavaDoc("One"));
296         panel.add(new Checkbox JavaDoc("Two"));
297         panel.add(new Checkbox JavaDoc("Three"));
298         panel.add(new Checkbox JavaDoc("Four"));
299         panel.add(new Checkbox JavaDoc("Five"));
300         panel.add(new Checkbox JavaDoc("One"));
301         panel.add(new Checkbox JavaDoc("Two"));
302         panel.add(new Checkbox JavaDoc("Three"));
303         panel.add(new Checkbox JavaDoc("Four"));
304         panel.add(new Checkbox JavaDoc("Five"));
305
306         frame.add(panel);
307         frame.setSize(300, 500);
308         frame.setVisible(true);
309     }
310
311 }
312
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