1 /* PopupFactory.java -- 2 Copyright (C) 2003 Free Software Foundation, Inc. 3 4 This file is part of GNU Classpath. 5 6 GNU Classpath is free software; you can redistribute it and/or modify 7 it under the terms of the GNU General Public License as published by 8 the Free Software Foundation; either version 2, or (at your option) 9 any later version. 10 11 GNU Classpath is distributed in the hope that it will be useful, but 12 WITHOUT ANY WARRANTY; without even the implied warranty of 13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 14 General Public License for more details. 15 16 You should have received a copy of the GNU General Public License 17 along with GNU Classpath; see the file COPYING. If not, write to the 18 Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 19 02110-1301 USA. 20 21 Linking this library statically or dynamically with other modules is 22 making a combined work based on this library. Thus, the terms and 23 conditions of the GNU General Public License cover the whole 24 combination. 25 26 As a special exception, the copyright holders of this library give you 27 permission to link this library with independent modules to produce an 28 executable, regardless of the license terms of these independent 29 modules, and to copy and distribute the resulting executable under 30 terms of your choice, provided that you also meet, for each linked 31 independent module, the terms and conditions of the license of that 32 module. An independent module is a module which is not derived from 33 or based on this library. If you modify this library, you may extend 34 this exception to your version of the library, but you are not 35 obligated to do so. If you do not wish to do so, delete this 36 exception statement from your version. */ 37 38 39 package javax.swing; 40 41 import java.awt.Component; 42 import java.awt.Dimension; 43 import java.awt.Point; 44 45 46 /** 47 * A factory for <code>Popup</code> objects. These are used to 48 * managed little windows that float over everything else, 49 * typically containing a popup menu. 50 * 51 * @since 1.4 52 * 53 * @author Sascha Brawer (brawer@dandelis.ch) 54 */ 55 public class PopupFactory 56 { 57 /** 58 * The shared factory object. 59 * 60 * @see #getSharedInstance 61 * @see #setSharedInstance 62 */ 63 private static PopupFactory sharedFactory; 64 65 66 /** 67 * Constructs a new <code>PopupFactory</code>. Usually, a single 68 * <code>PopupFactory</code> is shared among multiple consumers 69 * of <code>Popup</code>. Use {@link #getSharedInstance} to retrieve 70 * the current factory. 71 */ PopupFactory()72 public PopupFactory() 73 { 74 // Nothing to do here. 75 } 76 77 78 /** 79 * Sets the shared factory. 80 * 81 * @param factory the PopupFactory that future invocations of 82 * {@link #getSharedInstance} will return. 83 * 84 * @throws IllegalArgumentException if <code>factory</code> 85 * is <code>null</code>. 86 */ setSharedInstance(PopupFactory factory)87 public static void setSharedInstance(PopupFactory factory) 88 { 89 if (factory == null) 90 throw new IllegalArgumentException(); 91 92 /* Swing is not designed to be thread-safe, so there is no 93 * need to synchronize the access to the global variable. 94 */ 95 sharedFactory = factory; 96 } 97 98 99 /** 100 * Retrieves the shared factory, creating a new factory if 101 * necessary. 102 * 103 * @return a <code>PopupFactory</code> that can be used 104 * to create <code>Popup</code> objects. 105 */ getSharedInstance()106 public static PopupFactory getSharedInstance() 107 { 108 /* Swing is not designed to be thread-safe, so there is no 109 * need to synchronize the access to the global variable. 110 */ 111 if (sharedFactory == null) 112 sharedFactory = new PopupFactory(); 113 114 return sharedFactory; 115 } 116 117 118 /** 119 * Creates a new <code>Popup</code> given its owner, 120 * contents and the screen position where the popup 121 * will appear. 122 * 123 * @param owner the Component to which <code>x</code> and 124 * <code>y</code> are relative, or <code>null</code> for 125 * placing the popup relative to the origin of the screen. 126 * 127 * @param contents the contents that will be displayed inside 128 * the <code>Popup</code>. 129 * 130 * @param x the horizontal position where the Popup will appear. 131 * 132 * @param y the vertical position where the Popup will appear. 133 * 134 * @throws IllegalArgumentException if <code>contents</code> 135 * is <code>null</code>. 136 */ getPopup(Component owner, Component contents, int x, int y)137 public Popup getPopup(Component owner, Component contents, 138 int x, int y) 139 { 140 Popup popup = null; 141 // By default we enable lightweight popups since they are more efficient 142 // than heavyweight popups. 143 boolean lightweightEnabled = true; 144 // Special case JPopupMenu here, since it supports a lightweightEnabled 145 // flag that we must respect. 146 if (contents instanceof JPopupMenu) 147 { 148 JPopupMenu menu = (JPopupMenu) contents; 149 lightweightEnabled = menu.isLightWeightPopupEnabled(); 150 } 151 152 // If we have a root pane and the contents fits within the root pane and 153 // lightweight popups are enabled, than we can use a lightweight popup. 154 JRootPane root = SwingUtilities.getRootPane(owner); 155 if (root != null) 156 { 157 Point rootLoc = root.getLocationOnScreen(); 158 Dimension contentsSize = contents.getSize(); 159 Dimension rootSize = root.getSize(); 160 if (x >= rootLoc.x && y > rootLoc.y 161 && (x - rootLoc.x) + contentsSize.width < rootSize.width 162 && (y - rootLoc.y) + contentsSize.height < rootSize.height) 163 popup = new Popup.LightweightPopup(owner, contents, x, y); 164 else 165 popup = new Popup.JWindowPopup(owner, contents, x, y); 166 } 167 else 168 popup = new Popup.JWindowPopup(owner, contents, x, y); 169 return popup; 170 } 171 } 172