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 }