001    /* BasicSeparatorUI.java --
002       Copyright (C) 2004 Free Software Foundation, Inc.
003    
004    This file is part of GNU Classpath.
005    
006    GNU Classpath is free software; you can redistribute it and/or modify
007    it under the terms of the GNU General Public License as published by
008    the Free Software Foundation; either version 2, or (at your option)
009    any later version.
010    
011    GNU Classpath is distributed in the hope that it will be useful, but
012    WITHOUT ANY WARRANTY; without even the implied warranty of
013    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
014    General Public License for more details.
015    
016    You should have received a copy of the GNU General Public License
017    along with GNU Classpath; see the file COPYING.  If not, write to the
018    Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
019    02110-1301 USA.
020    
021    Linking this library statically or dynamically with other modules is
022    making a combined work based on this library.  Thus, the terms and
023    conditions of the GNU General Public License cover the whole
024    combination.
025    
026    As a special exception, the copyright holders of this library give you
027    permission to link this library with independent modules to produce an
028    executable, regardless of the license terms of these independent
029    modules, and to copy and distribute the resulting executable under
030    terms of your choice, provided that you also meet, for each linked
031    independent module, the terms and conditions of the license of that
032    module.  An independent module is a module which is not derived from
033    or based on this library.  If you modify this library, you may extend
034    this exception to your version of the library, but you are not
035    obligated to do so.  If you do not wish to do so, delete this
036    exception statement from your version. */
037    
038    
039    package javax.swing.plaf.basic;
040    
041    import java.awt.Color;
042    import java.awt.Dimension;
043    import java.awt.Graphics;
044    import java.awt.Rectangle;
045    
046    import javax.swing.JComponent;
047    import javax.swing.JSeparator;
048    import javax.swing.SwingUtilities;
049    import javax.swing.UIManager;
050    import javax.swing.plaf.ComponentUI;
051    import javax.swing.plaf.SeparatorUI;
052    
053    /**
054     * The Basic Look and Feel UI delegate for JSeparator.
055     */
056    public class BasicSeparatorUI extends SeparatorUI
057    {
058      /** The shadow color. */
059      protected Color shadow;
060    
061      /** The highlight color. */
062      protected Color highlight;
063    
064      /**
065       * Creates a new UI delegate for the given JComponent.
066       *
067       * @param c The JComponent to create a delegate for.
068       *
069       * @return A new BasicSeparatorUI.
070       */
071      public static ComponentUI createUI(JComponent c)
072      {
073        return new BasicSeparatorUI();
074      }
075    
076      /**
077       * This method installs the UI for the given JComponent.
078       * This can include installing defaults, listeners, and
079       * initializing any instance data.
080       *
081       * @param c The JComponent that is having this UI installed.
082       */
083      public void installUI(JComponent c)
084      {
085        super.installUI(c);
086    
087        if (c instanceof JSeparator)
088          {
089            JSeparator s = (JSeparator) c;
090    
091            installDefaults(s);
092            installListeners(s);
093          }
094      }
095    
096      /**
097       * Uninstalls the UI for the given JComponent. This
098       * method reverses what was done when installing
099       * the UI on the JComponent.
100       *
101       * @param c The JComponent that is having this UI uninstalled.
102       */
103      public void uninstallUI(JComponent c)
104      {
105        if (c instanceof JSeparator)
106          {
107            JSeparator s = (JSeparator) c;
108    
109            uninstallListeners(s);
110            uninstallDefaults(s);
111          }
112      }
113    
114      /**
115       * This method installs the defaults that are given by
116       * the Basic Look and Feel.
117       *
118       * @param s The JSeparator that is being installed.
119       */
120      protected void installDefaults(JSeparator s)
121      {
122        shadow = UIManager.getColor("Separator.shadow");
123        highlight = UIManager.getColor("Separator.highlight");
124        s.setOpaque(false);
125      }
126    
127      /**
128       * This method removes the defaults that were given
129       * by the Basic Look and Feel.
130       *
131       * @param s The JSeparator that is being uninstalled.
132       */
133      protected void uninstallDefaults(JSeparator s)
134      {
135        shadow = null;
136        highlight = null;
137      }
138    
139      /**
140       * This method installs any listeners that need
141       * to be attached to the JSeparator or any of its 
142       * components.
143       *
144       * @param s The JSeparator that is being installed.
145       */
146      protected void installListeners(JSeparator s)
147      {
148        // Separators don't receive events.
149      }
150    
151      /**
152       * This method uninstalls any listeners that
153       * were installed during the install UI process.
154       *
155       * @param s The JSeparator that is being uninstalled.
156       */
157      protected void uninstallListeners(JSeparator s)
158      {
159        // Separators don't receive events.  
160      }
161    
162      /**
163       * The separator is made of two lines. The top line will be 
164       * the shadow color (or left line if it's vertical). The bottom 
165       * or right line will be the highlight color. The two lines will 
166       * be centered inside the bounds box. If the separator is horizontal, 
167       * then it will be vertically centered, or if it's vertical, it will 
168       * be horizontally centered.
169       *
170       * @param g The Graphics object to paint with
171       * @param c The JComponent to paint.
172       */
173      public void paint(Graphics g, JComponent c)
174      {
175        Rectangle r = new Rectangle();
176        SwingUtilities.calculateInnerArea(c, r);
177        Color saved = g.getColor();
178        
179        JSeparator s;
180        if (c instanceof JSeparator)
181          s = (JSeparator) c;
182        else
183          return;
184          
185        if (s.getOrientation() == JSeparator.HORIZONTAL)
186          {    
187            int midAB = r.height / 2;
188            g.setColor(shadow);
189            g.drawLine(r.x, r.y + midAB - 1, r.x + r.width, r.y + midAB - 1);
190    
191            g.setColor(highlight);
192            g.fillRect(r.x, r.y + midAB, r.x + r.width, r.y + midAB);
193          }
194          else
195          {
196            int midAD = r.height / 2 + r.y;
197            g.setColor(shadow);
198            g.drawLine(r.x, r.y, r.x, r.y + r.height);
199    
200            g.setColor(highlight);
201            g.fillRect(r.x + midAD, r.y + r.height, r.x + midAD, r.y + r.height);
202          }
203        g.setColor(saved);
204      }
205    
206      /**
207       * This method returns the preferred size of the 
208       * JComponent.
209       *
210       * @param c The JComponent to measure.
211       *
212       * @return The preferred size.
213       */
214      public Dimension getPreferredSize(JComponent c)
215      {
216        Dimension pref = new Dimension(2, 0);
217        if (c instanceof JSeparator)
218          {
219            JSeparator s = (JSeparator) c;
220            if (s.getOrientation() == JSeparator.HORIZONTAL)
221              pref = new Dimension(0, 2);
222          }
223        return pref;
224      }
225    
226      /**
227       * This method returns the minimum size of the
228       * JComponent.
229       *
230       * @param c The JComponent to measure.
231       *
232       * @return The minimum size.
233       */
234      public Dimension getMinimumSize(JComponent c)
235      {
236        return new Dimension(0, 0);
237      }
238    
239      /**
240       * This method returns the maximum size of the
241       * JComponent.
242       *
243       * @param c The JComponent to measure.
244       *
245       * @return The maximum size.
246       */
247      public Dimension getMaximumSize(JComponent c)
248      {
249        return new Dimension(Short.MAX_VALUE,
250                             Short.MAX_VALUE);
251      }
252    }