jdk/src/share/classes/javax/swing/DefaultListCellRenderer.java
changeset 2 90ce3da70b43
child 2658 43e06bc950ec
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/jdk/src/share/classes/javax/swing/DefaultListCellRenderer.java	Sat Dec 01 00:00:00 2007 +0000
@@ -0,0 +1,325 @@
+/*
+ * Copyright 1998-2007 Sun Microsystems, Inc.  All Rights Reserved.
+ * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
+ *
+ * This code is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 only, as
+ * published by the Free Software Foundation.  Sun designates this
+ * particular file as subject to the "Classpath" exception as provided
+ * by Sun in the LICENSE file that accompanied this code.
+ *
+ * This code is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+ * version 2 for more details (a copy is included in the LICENSE file that
+ * accompanied this code).
+ *
+ * You should have received a copy of the GNU General Public License version
+ * 2 along with this work; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
+ * CA 95054 USA or visit www.sun.com if you need additional information or
+ * have any questions.
+ */
+
+package javax.swing;
+
+import javax.swing.*;
+import javax.swing.event.*;
+import javax.swing.border.*;
+
+import java.awt.Component;
+import java.awt.Color;
+import java.awt.Rectangle;
+
+import java.io.Serializable;
+
+
+/**
+ * Renders an item in a list.
+ * <p>
+ * <strong><a name="override">Implementation Note:</a></strong>
+ * This class overrides
+ * <code>invalidate</code>,
+ * <code>validate</code>,
+ * <code>revalidate</code>,
+ * <code>repaint</code>,
+ * <code>isOpaque</code>,
+ * and
+ * <code>firePropertyChange</code>
+ * solely to improve performance.
+ * If not overridden, these frequently called methods would execute code paths
+ * that are unnecessary for the default list cell renderer.
+ * If you write your own renderer,
+ * take care to weigh the benefits and
+ * drawbacks of overriding these methods.
+ *
+ * <p>
+ *
+ * <strong>Warning:</strong>
+ * Serialized objects of this class will not be compatible with
+ * future Swing releases. The current serialization support is
+ * appropriate for short term storage or RMI between applications running
+ * the same version of Swing.  As of 1.4, support for long term storage
+ * of all JavaBeans<sup><font size="-2">TM</font></sup>
+ * has been added to the <code>java.beans</code> package.
+ * Please see {@link java.beans.XMLEncoder}.
+ *
+ * @author Philip Milne
+ * @author Hans Muller
+ */
+public class DefaultListCellRenderer extends JLabel
+    implements ListCellRenderer, Serializable
+{
+
+   /**
+    * An empty <code>Border</code>. This field might not be used. To change the
+    * <code>Border</code> used by this renderer override the
+    * <code>getListCellRendererComponent</code> method and set the border
+    * of the returned component directly.
+    */
+    protected static Border noFocusBorder = new EmptyBorder(1, 1, 1, 1);
+    private static final Border SAFE_NO_FOCUS_BORDER = new EmptyBorder(1, 1, 1, 1);
+
+    /**
+     * Constructs a default renderer object for an item
+     * in a list.
+     */
+    public DefaultListCellRenderer() {
+        super();
+        setOpaque(true);
+        setBorder(getNoFocusBorder());
+    }
+
+
+    private static Border getNoFocusBorder() {
+        if (System.getSecurityManager() != null) {
+            return SAFE_NO_FOCUS_BORDER;
+        } else {
+            return UIManager.getBorder("List.noFocusBorder");
+        }
+    }
+
+    public Component getListCellRendererComponent(
+        JList list,
+        Object value,
+        int index,
+        boolean isSelected,
+        boolean cellHasFocus)
+    {
+        setComponentOrientation(list.getComponentOrientation());
+
+        Color bg = null;
+        Color fg = null;
+
+        JList.DropLocation dropLocation = list.getDropLocation();
+        if (dropLocation != null
+                && !dropLocation.isInsert()
+                && dropLocation.getIndex() == index) {
+
+            bg = UIManager.getColor("List.dropCellBackground");
+            fg = UIManager.getColor("List.dropCellForeground");
+
+            isSelected = true;
+        }
+
+        if (isSelected) {
+            setBackground(bg == null ? list.getSelectionBackground() : bg);
+            setForeground(fg == null ? list.getSelectionForeground() : fg);
+        }
+        else {
+            setBackground(list.getBackground());
+            setForeground(list.getForeground());
+        }
+
+        if (value instanceof Icon) {
+            setIcon((Icon)value);
+            setText("");
+        }
+        else {
+            setIcon(null);
+            setText((value == null) ? "" : value.toString());
+        }
+
+        setEnabled(list.isEnabled());
+        setFont(list.getFont());
+
+        Border border = null;
+        if (cellHasFocus) {
+            if (isSelected) {
+                border = UIManager.getBorder("List.focusSelectedCellHighlightBorder");
+            }
+            if (border == null) {
+                border = UIManager.getBorder("List.focusCellHighlightBorder");
+            }
+        } else {
+            border = getNoFocusBorder();
+        }
+        setBorder(border);
+
+        return this;
+    }
+
+
+    /**
+     * Overridden for performance reasons.
+     * See the <a href="#override">Implementation Note</a>
+     * for more information.
+     *
+     * @since 1.5
+     * @return <code>true</code> if the background is completely opaque
+     *         and differs from the JList's background;
+     *         <code>false</code> otherwise
+     */
+    public boolean isOpaque() {
+        Color back = getBackground();
+        Component p = getParent();
+        if (p != null) {
+            p = p.getParent();
+        }
+        // p should now be the JList.
+        boolean colorMatch = (back != null) && (p != null) &&
+            back.equals(p.getBackground()) &&
+                        p.isOpaque();
+        return !colorMatch && super.isOpaque();
+    }
+
+   /**
+    * Overridden for performance reasons.
+    * See the <a href="#override">Implementation Note</a>
+    * for more information.
+    */
+    public void validate() {}
+
+   /**
+    * Overridden for performance reasons.
+    * See the <a href="#override">Implementation Note</a>
+    * for more information.
+    *
+    * @since 1.5
+    */
+    public void invalidate() {}
+
+   /**
+    * Overridden for performance reasons.
+    * See the <a href="#override">Implementation Note</a>
+    * for more information.
+    *
+    * @since 1.5
+    */
+    public void repaint() {}
+
+   /**
+    * Overridden for performance reasons.
+    * See the <a href="#override">Implementation Note</a>
+    * for more information.
+    */
+    public void revalidate() {}
+   /**
+    * Overridden for performance reasons.
+    * See the <a href="#override">Implementation Note</a>
+    * for more information.
+    */
+    public void repaint(long tm, int x, int y, int width, int height) {}
+
+   /**
+    * Overridden for performance reasons.
+    * See the <a href="#override">Implementation Note</a>
+    * for more information.
+    */
+    public void repaint(Rectangle r) {}
+
+   /**
+    * Overridden for performance reasons.
+    * See the <a href="#override">Implementation Note</a>
+    * for more information.
+    */
+    protected void firePropertyChange(String propertyName, Object oldValue, Object newValue) {
+        // Strings get interned...
+        if (propertyName == "text"
+                || ((propertyName == "font" || propertyName == "foreground")
+                    && oldValue != newValue
+                    && getClientProperty(javax.swing.plaf.basic.BasicHTML.propertyKey) != null)) {
+
+            super.firePropertyChange(propertyName, oldValue, newValue);
+        }
+    }
+
+   /**
+    * Overridden for performance reasons.
+    * See the <a href="#override">Implementation Note</a>
+    * for more information.
+    */
+    public void firePropertyChange(String propertyName, byte oldValue, byte newValue) {}
+
+   /**
+    * Overridden for performance reasons.
+    * See the <a href="#override">Implementation Note</a>
+    * for more information.
+    */
+    public void firePropertyChange(String propertyName, char oldValue, char newValue) {}
+
+   /**
+    * Overridden for performance reasons.
+    * See the <a href="#override">Implementation Note</a>
+    * for more information.
+    */
+    public void firePropertyChange(String propertyName, short oldValue, short newValue) {}
+
+   /**
+    * Overridden for performance reasons.
+    * See the <a href="#override">Implementation Note</a>
+    * for more information.
+    */
+    public void firePropertyChange(String propertyName, int oldValue, int newValue) {}
+
+   /**
+    * Overridden for performance reasons.
+    * See the <a href="#override">Implementation Note</a>
+    * for more information.
+    */
+    public void firePropertyChange(String propertyName, long oldValue, long newValue) {}
+
+   /**
+    * Overridden for performance reasons.
+    * See the <a href="#override">Implementation Note</a>
+    * for more information.
+    */
+    public void firePropertyChange(String propertyName, float oldValue, float newValue) {}
+
+   /**
+    * Overridden for performance reasons.
+    * See the <a href="#override">Implementation Note</a>
+    * for more information.
+    */
+    public void firePropertyChange(String propertyName, double oldValue, double newValue) {}
+
+   /**
+    * Overridden for performance reasons.
+    * See the <a href="#override">Implementation Note</a>
+    * for more information.
+    */
+    public void firePropertyChange(String propertyName, boolean oldValue, boolean newValue) {}
+
+    /**
+     * A subclass of DefaultListCellRenderer that implements UIResource.
+     * DefaultListCellRenderer doesn't implement UIResource
+     * directly so that applications can safely override the
+     * cellRenderer property with DefaultListCellRenderer subclasses.
+     * <p>
+     * <strong>Warning:</strong>
+     * Serialized objects of this class will not be compatible with
+     * future Swing releases. The current serialization support is
+     * appropriate for short term storage or RMI between applications running
+     * the same version of Swing.  As of 1.4, support for long term storage
+     * of all JavaBeans<sup><font size="-2">TM</font></sup>
+     * has been added to the <code>java.beans</code> package.
+     * Please see {@link java.beans.XMLEncoder}.
+     */
+    public static class UIResource extends DefaultListCellRenderer
+        implements javax.swing.plaf.UIResource
+    {
+    }
+
+}