1 /* 2 * Copyright (c) 1997, 2006, Oracle and/or its affiliates. All rights reserved. 3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. 4 * 5 * This code is free software; you can redistribute it and/or modify it 6 * under the terms of the GNU General Public License version 2 only, as 7 * published by the Free Software Foundation. Oracle designates this 8 * particular file as subject to the "Classpath" exception as provided 9 * by Oracle in the LICENSE file that accompanied this code. 10 * 11 * This code is distributed in the hope that it will be useful, but WITHOUT 12 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 13 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 14 * version 2 for more details (a copy is included in the LICENSE file that 15 * accompanied this code). 16 * 17 * You should have received a copy of the GNU General Public License version 18 * 2 along with this work; if not, write to the Free Software Foundation, 19 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. 20 * 21 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA 22 * or visit www.oracle.com if you need additional information or have any 23 * questions. 24 */ 25 26 package javax.swing.plaf; 27 28 import javax.swing.JList; 29 import java.awt.Point; 30 import java.awt.Rectangle; 31 32 33 /** 34 * The {@code JList} pluggable look and feel delegate. 35 * 36 * @author Hans Muller 37 */ 38 39 public abstract class ListUI extends ComponentUI 40 { 41 /** 42 * Returns the cell index in the specified {@code JList} closest to the 43 * given location in the list's coordinate system. To determine if the 44 * cell actually contains the specified location, compare the point against 45 * the cell's bounds, as provided by {@code getCellBounds}. 46 * This method returns {@code -1} if the list's model is empty. 47 * 48 * @param list the list 49 * @param location the coordinates of the point 50 * @return the cell index closest to the given location, or {@code -1} 51 * @throws NullPointerException if {@code location} is null 52 */ 53 public abstract int locationToIndex(JList list, Point location); 54 55 56 /** 57 * Returns the origin in the given {@code JList}, of the specified item, 58 * in the list's coordinate system. 59 * Returns {@code null} if the index isn't valid. 60 * 61 * @param list the list 62 * @param index the cell index 63 * @return the origin of the cell, or {@code null} 64 */ 65 public abstract Point indexToLocation(JList list, int index); 66 67 68 /** 69 * Returns the bounding rectangle, in the given list's coordinate system, 70 * for the range of cells specified by the two indices. 71 * The indices can be supplied in any order. 72 * <p> 73 * If the smaller index is outside the list's range of cells, this method 74 * returns {@code null}. If the smaller index is valid, but the larger 75 * index is outside the list's range, the bounds of just the first index 76 * is returned. Otherwise, the bounds of the valid range is returned. 77 * 78 * @param list the list 79 * @param index1 the first index in the range 80 * @param index2 the second index in the range 81 * @return the bounding rectangle for the range of cells, or {@code null} 82 */ 83 public abstract Rectangle getCellBounds(JList list, int index1, int index2); 84 }