001 /* ListUI.java --
002 Copyright (C) 2002, 2003, 2004, 2005 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;
040
041 import java.awt.Point;
042 import java.awt.Rectangle;
043
044 import javax.swing.JList;
045
046 /**
047 * An abstract base class for delegates that implement the pluggable
048 * look and feel for a <code>JList</code>.
049 *
050 * @author Sascha Brawer (brawer@dandelis.ch)
051 */
052 public abstract class ListUI extends ComponentUI
053 {
054 /**
055 * Constructs a new <code>ListUI</code>.
056 */
057 public ListUI()
058 {
059 // Nothing to do here.
060 }
061
062
063 /**
064 * Determines the cell index which is the closest to the specified
065 * location. The find out whether the returned cell actually
066 * contains the location, the caller should also use {@link
067 * #getCellBounds}.
068 *
069 * @param list the <code>JList</code> for which this delegate object
070 * provides the pluggable user interface.
071 *
072 * @param location a point in the <code>JList</code> coordinate
073 * system.
074 *
075 * @return the index of the closest cell, or -1 if the list model
076 * is empty.
077 */
078 public abstract int locationToIndex(JList list, Point location);
079
080
081 /**
082 * Determines the location of the specified cell.
083 *
084 * @param list the <code>JList</code> for which this delegate object
085 * provides the pluggable user interface.
086 *
087 * @param index the zero-based index of the cell whose location shall be
088 * determined.
089 *
090 * @return the position of the top left corner of the cell in the
091 * <code>JList</code> coordinate system, or <code>null</code>
092 * if <code>cell</code> does not designate a valid cell.
093 */
094 public abstract Point indexToLocation(JList list, int index);
095
096
097 /**
098 * Determines the bounding box of the rectangle spanned by
099 * two list indices.
100 *
101 * @param list the <code>JList</code> for which this delegate object
102 * provides the pluggable user interface.
103 *
104 * @param index1 the zero-based index of the first cell.
105 *
106 * @param index2 the zero-based index of the second cell.
107 *
108 * @return the spanned rectangle, or <code>null</code> if either
109 * <code>index1</code> or <code>index2</code> does not
110 * designate a valid cell.
111 */
112 public abstract Rectangle getCellBounds(JList list,
113 int index1, int index2);
114 }