001/*
002 * $Id: DefaultListRenderer.java 3779 2010-09-07 18:01:55Z kschaefe $
003 *
004 * Copyright 2006 Sun Microsystems, Inc., 4150 Network Circle,
005 * Santa Clara, California 95054, U.S.A. All rights reserved.
006 *
007 * This library is free software; you can redistribute it and/or
008 * modify it under the terms of the GNU Lesser General Public
009 * License as published by the Free Software Foundation; either
010 * version 2.1 of the License, or (at your option) any later version.
011 * 
012 * This library is distributed in the hope that it will be useful,
013 * but WITHOUT ANY WARRANTY; without even the implied warranty of
014 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
015 * Lesser General Public License for more details.
016 * 
017 * You should have received a copy of the GNU Lesser General Public
018 * License along with this library; if not, write to the Free Software
019 * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
020 */
021package org.jdesktop.swingx.renderer;
022
023import java.awt.Component;
024
025import javax.swing.JList;
026import javax.swing.ListCellRenderer;
027
028/**
029 * Adapter to glue SwingX renderer support to core API. It has convenience
030 * constructors to create a LabelProvider, optionally configured with a
031 * StringValue and horizontal alignment. Typically, client code does not
032 * interact with this class except at instantiation time.
033 * <p>
034 * 
035 * Note: core DefaultListCellRenderer shows either an icon or the element's
036 * toString representation, depending on whether or not the given value 
037 * is of type icon or implementors. This renderer's empty/null provider 
038 * constructor takes care of configuring the default provider with a converter
039 * which mimics that behaviour. When instantiating this renderer with
040 * any of the constructors which have converters as parameters,
041 * it's up to the client code to supply the appropriate converter, if needed:
042 * 
043 * 
044 * <pre><code>
045 * StringValue sv = new StringValue() {
046 * 
047 *     public String getString(Object value) {
048 *         if (value instanceof Icon) {
049 *             return &quot;&quot;;
050 *         }
051 *         return StringValue.TO_STRING.getString(value);
052 *     }
053 * 
054 * };
055 * StringValue lv = new MappedValue(sv, IconValue.ICON);
056 * listRenderer = new DefaultListRenderer(lv, alignment);
057 * 
058 * </code></pre>
059 * 
060 * <p>
061 * 
062 * 
063 * @author Jeanette Winzenburg
064 * 
065 * @see ComponentProvider
066 * @see StringValue
067 * @see IconValue
068 * @see MappedValue
069 * 
070 * 
071 */
072public class DefaultListRenderer extends AbstractRenderer
073    implements ListCellRenderer {
074
075    protected ListCellContext cellContext;
076
077    /**
078     * Instantiates a default list renderer with the default component
079     * provider.
080     *
081     */
082    public DefaultListRenderer() {
083        this((ComponentProvider<?>) null);
084    }
085
086    /**
087     * Instantiates a ListCellRenderer with the given ComponentProvider.
088     * If the provider is null, creates and uses a default. The default
089     * provider is of type <code>LabelProvider</code><p>
090     * 
091     * Note: the default provider is configured with a custom StringValue
092     * which behaves exactly as core DefaultListCellRenderer: depending on 
093     * whether or not given value is of type icon or implementors, it shows 
094     * either the icon or the element's toString.  
095     * 
096     * @param componentProvider the provider of the configured component to
097     *   use for cell rendering
098     */
099    public DefaultListRenderer(ComponentProvider<?> componentProvider) {
100        super(componentProvider);
101        this.cellContext = new ListCellContext();
102    }
103
104    /**
105     * Instantiates a default table renderer with a default component controller
106     * using the given converter.<p>
107     * 
108     * PENDING JW: how to guarantee core consistent icon handling? Leave to 
109     * client code?
110     * 
111     * @param converter the converter to use for mapping the content value to a
112     *        String representation.
113     * 
114     */
115    public DefaultListRenderer(StringValue converter) {
116        this(new LabelProvider(converter));
117    }
118
119    /**
120     * Instantiates a default list renderer with a default component
121     * controller using the given converter and horizontal 
122     * alignment. 
123     * 
124     * PENDING JW: how to guarantee core consistent icon handling? Leave to
125     * client code?
126     * 
127     * 
128     * @param converter the converter to use for mapping the
129     *   content value to a String representation.
130     * @param alignment the horizontal alignment.
131     */
132    public DefaultListRenderer(StringValue converter, int alignment) {
133        this(new LabelProvider(converter, alignment));
134    }
135
136    
137    /**
138     * Instantiates a default list renderer with default component provider
139     * using both converters.
140     * 
141     * @param stringValue the converter to use for the string representation
142     * @param iconValue the converter to use for the icon representation
143     */
144    public DefaultListRenderer(StringValue stringValue, IconValue iconValue) {
145        this(new MappedValue(stringValue, iconValue));
146    }
147
148    /**
149     * Instantiates a default list renderer with default component provider
150     * using both converters and the given alignment.
151     * 
152     * @param stringValue the converter to use for the string representation
153     * @param iconValue the converter to use for the icon representation
154     * @param alignment the rendering component's horizontal alignment
155     */
156    public DefaultListRenderer(StringValue stringValue, IconValue iconValue,
157            int alignment) {
158        this(new MappedValue(stringValue, iconValue), alignment);
159    }
160
161    // -------------- implements javax.swing.table.ListCellRenderer
162    /**
163     * 
164     * Returns a configured component, appropriate to render the given
165     * list cell.  <p>
166     * 
167     * Note: The component's name is set to "List.cellRenderer" for the sake
168     * of Synth-based LAFs.
169     * 
170     * @param list the <code>JList</code> to render on
171     * @param value the value to assign to the cell 
172     * @param isSelected true if cell is selected
173     * @param cellHasFocus true if cell has focus
174     * @param index the row index (in view coordinates) of the cell to render
175     * @return a component to render the given list cell.
176     */
177    @Override
178    public Component getListCellRendererComponent(JList list, Object value,
179            int index, boolean isSelected, boolean cellHasFocus) {
180        cellContext.installContext(list, value, index, 0, isSelected,
181                cellHasFocus, true, true);
182        Component comp = componentController.getRendererComponent(cellContext);
183        // fix issue #1040-swingx: memory leak if value not released
184        cellContext.replaceValue(null);
185        return comp;
186    }
187
188    /**
189     * {@inheritDoc}
190     */ 
191    @Override
192    protected ComponentProvider<?> createDefaultComponentProvider() {
193        return new LabelProvider(createDefaultStringValue());
194    }
195
196    /**
197     * Creates and returns the default StringValue for a JList.<p>
198     * This is added to keep consistent with core list rendering which
199     * shows either the Icon (for Icon value types) or the default 
200     * to-string for non-icon types.
201     * 
202     * @return the StringValue to use by default.
203     */
204    private StringValue createDefaultStringValue() {
205        return MappedValues.STRING_OR_ICON_ONLY;
206    }
207}