J. Duke | 319a3b9 | 2007-12-01 00:00:00 +0000 | [diff] [blame^] | 1 | /* |
| 2 | * Copyright 1997-2006 Sun Microsystems, Inc. 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. Sun designates this |
| 8 | * particular file as subject to the "Classpath" exception as provided |
| 9 | * by Sun 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 Sun Microsystems, Inc., 4150 Network Circle, Santa Clara, |
| 22 | * CA 95054 USA or visit www.sun.com if you need additional information or |
| 23 | * have any questions. |
| 24 | */ |
| 25 | |
| 26 | |
| 27 | package javax.swing; |
| 28 | import javax.swing.plaf.*; |
| 29 | import javax.accessibility.*; |
| 30 | |
| 31 | import java.io.ObjectOutputStream; |
| 32 | import java.io.ObjectInputStream; |
| 33 | import java.io.IOException; |
| 34 | |
| 35 | |
| 36 | /** |
| 37 | * Used to display a "Tip" for a Component. Typically components provide api |
| 38 | * to automate the process of using <code>ToolTip</code>s. |
| 39 | * For example, any Swing component can use the <code>JComponent</code> |
| 40 | * <code>setToolTipText</code> method to specify the text |
| 41 | * for a standard tooltip. A component that wants to create a custom |
| 42 | * <code>ToolTip</code> |
| 43 | * display can override <code>JComponent</code>'s <code>createToolTip</code> |
| 44 | * method and use a subclass of this class. |
| 45 | * <p> |
| 46 | * See <a href="http://java.sun.com/docs/books/tutorial/uiswing/components/tooltip.html">How to Use Tool Tips</a> |
| 47 | * in <em>The Java Tutorial</em> |
| 48 | * for further documentation. |
| 49 | * <p> |
| 50 | * <strong>Warning:</strong> Swing is not thread safe. For more |
| 51 | * information see <a |
| 52 | * href="package-summary.html#threading">Swing's Threading |
| 53 | * Policy</a>. |
| 54 | * <p> |
| 55 | * <strong>Warning:</strong> |
| 56 | * Serialized objects of this class will not be compatible with |
| 57 | * future Swing releases. The current serialization support is |
| 58 | * appropriate for short term storage or RMI between applications running |
| 59 | * the same version of Swing. As of 1.4, support for long term storage |
| 60 | * of all JavaBeans<sup><font size="-2">TM</font></sup> |
| 61 | * has been added to the <code>java.beans</code> package. |
| 62 | * Please see {@link java.beans.XMLEncoder}. |
| 63 | * |
| 64 | * @see JComponent#setToolTipText |
| 65 | * @see JComponent#createToolTip |
| 66 | * @author Dave Moore |
| 67 | * @author Rich Shiavi |
| 68 | */ |
| 69 | public class JToolTip extends JComponent implements Accessible { |
| 70 | /** |
| 71 | * @see #getUIClassID |
| 72 | * @see #readObject |
| 73 | */ |
| 74 | private static final String uiClassID = "ToolTipUI"; |
| 75 | |
| 76 | String tipText; |
| 77 | JComponent component; |
| 78 | |
| 79 | /** Creates a tool tip. */ |
| 80 | public JToolTip() { |
| 81 | setOpaque(true); |
| 82 | updateUI(); |
| 83 | } |
| 84 | |
| 85 | /** |
| 86 | * Returns the L&F object that renders this component. |
| 87 | * |
| 88 | * @return the <code>ToolTipUI</code> object that renders this component |
| 89 | */ |
| 90 | public ToolTipUI getUI() { |
| 91 | return (ToolTipUI)ui; |
| 92 | } |
| 93 | |
| 94 | /** |
| 95 | * Resets the UI property to a value from the current look and feel. |
| 96 | * |
| 97 | * @see JComponent#updateUI |
| 98 | */ |
| 99 | public void updateUI() { |
| 100 | setUI((ToolTipUI)UIManager.getUI(this)); |
| 101 | } |
| 102 | |
| 103 | |
| 104 | /** |
| 105 | * Returns the name of the L&F class that renders this component. |
| 106 | * |
| 107 | * @return the string "ToolTipUI" |
| 108 | * @see JComponent#getUIClassID |
| 109 | * @see UIDefaults#getUI |
| 110 | */ |
| 111 | public String getUIClassID() { |
| 112 | return uiClassID; |
| 113 | } |
| 114 | |
| 115 | |
| 116 | /** |
| 117 | * Sets the text to show when the tool tip is displayed. |
| 118 | * The string <code>tipText</code> may be <code>null</code>. |
| 119 | * |
| 120 | * @param tipText the <code>String</code> to display |
| 121 | * @beaninfo |
| 122 | * preferred: true |
| 123 | * bound: true |
| 124 | * description: Sets the text of the tooltip |
| 125 | */ |
| 126 | public void setTipText(String tipText) { |
| 127 | String oldValue = this.tipText; |
| 128 | this.tipText = tipText; |
| 129 | firePropertyChange("tiptext", oldValue, tipText); |
| 130 | } |
| 131 | |
| 132 | /** |
| 133 | * Returns the text that is shown when the tool tip is displayed. |
| 134 | * The returned value may be <code>null</code>. |
| 135 | * |
| 136 | * @return the <code>String</code> that is displayed |
| 137 | */ |
| 138 | public String getTipText() { |
| 139 | return tipText; |
| 140 | } |
| 141 | |
| 142 | /** |
| 143 | * Specifies the component that the tooltip describes. |
| 144 | * The component <code>c</code> may be <code>null</code> |
| 145 | * and will have no effect. |
| 146 | * <p> |
| 147 | * This is a bound property. |
| 148 | * |
| 149 | * @param c the <code>JComponent</code> being described |
| 150 | * @see JComponent#createToolTip |
| 151 | * @beaninfo |
| 152 | * bound: true |
| 153 | * description: Sets the component that the tooltip describes. |
| 154 | */ |
| 155 | public void setComponent(JComponent c) { |
| 156 | JComponent oldValue = this.component; |
| 157 | |
| 158 | component = c; |
| 159 | firePropertyChange("component", oldValue, c); |
| 160 | } |
| 161 | |
| 162 | /** |
| 163 | * Returns the component the tooltip applies to. |
| 164 | * The returned value may be <code>null</code>. |
| 165 | * |
| 166 | * @return the component that the tooltip describes |
| 167 | * |
| 168 | * @see JComponent#createToolTip |
| 169 | */ |
| 170 | public JComponent getComponent() { |
| 171 | return component; |
| 172 | } |
| 173 | |
| 174 | /** |
| 175 | * Always returns true since tooltips, by definition, |
| 176 | * should always be on top of all other windows. |
| 177 | */ |
| 178 | // package private |
| 179 | boolean alwaysOnTop() { |
| 180 | return true; |
| 181 | } |
| 182 | |
| 183 | |
| 184 | /** |
| 185 | * See <code>readObject</code> and <code>writeObject</code> |
| 186 | * in <code>JComponent</code> for more |
| 187 | * information about serialization in Swing. |
| 188 | */ |
| 189 | private void writeObject(ObjectOutputStream s) throws IOException { |
| 190 | s.defaultWriteObject(); |
| 191 | if (getUIClassID().equals(uiClassID)) { |
| 192 | byte count = JComponent.getWriteObjCounter(this); |
| 193 | JComponent.setWriteObjCounter(this, --count); |
| 194 | if (count == 0 && ui != null) { |
| 195 | ui.installUI(this); |
| 196 | } |
| 197 | } |
| 198 | } |
| 199 | |
| 200 | |
| 201 | /** |
| 202 | * Returns a string representation of this <code>JToolTip</code>. |
| 203 | * This method |
| 204 | * is intended to be used only for debugging purposes, and the |
| 205 | * content and format of the returned string may vary between |
| 206 | * implementations. The returned string may be empty but may not |
| 207 | * be <code>null</code>. |
| 208 | * |
| 209 | * @return a string representation of this <code>JToolTip</code> |
| 210 | */ |
| 211 | protected String paramString() { |
| 212 | String tipTextString = (tipText != null ? |
| 213 | tipText : ""); |
| 214 | |
| 215 | return super.paramString() + |
| 216 | ",tipText=" + tipTextString; |
| 217 | } |
| 218 | |
| 219 | |
| 220 | ///////////////// |
| 221 | // Accessibility support |
| 222 | //////////////// |
| 223 | |
| 224 | /** |
| 225 | * Gets the AccessibleContext associated with this JToolTip. |
| 226 | * For tool tips, the AccessibleContext takes the form of an |
| 227 | * AccessibleJToolTip. |
| 228 | * A new AccessibleJToolTip instance is created if necessary. |
| 229 | * |
| 230 | * @return an AccessibleJToolTip that serves as the |
| 231 | * AccessibleContext of this JToolTip |
| 232 | */ |
| 233 | public AccessibleContext getAccessibleContext() { |
| 234 | if (accessibleContext == null) { |
| 235 | accessibleContext = new AccessibleJToolTip(); |
| 236 | } |
| 237 | return accessibleContext; |
| 238 | } |
| 239 | |
| 240 | /** |
| 241 | * This class implements accessibility support for the |
| 242 | * <code>JToolTip</code> class. It provides an implementation of the |
| 243 | * Java Accessibility API appropriate to tool tip user-interface elements. |
| 244 | * <p> |
| 245 | * <strong>Warning:</strong> |
| 246 | * Serialized objects of this class will not be compatible with |
| 247 | * future Swing releases. The current serialization support is |
| 248 | * appropriate for short term storage or RMI between applications running |
| 249 | * the same version of Swing. As of 1.4, support for long term storage |
| 250 | * of all JavaBeans<sup><font size="-2">TM</font></sup> |
| 251 | * has been added to the <code>java.beans</code> package. |
| 252 | * Please see {@link java.beans.XMLEncoder}. |
| 253 | */ |
| 254 | protected class AccessibleJToolTip extends AccessibleJComponent { |
| 255 | |
| 256 | /** |
| 257 | * Get the accessible description of this object. |
| 258 | * |
| 259 | * @return a localized String describing this object. |
| 260 | */ |
| 261 | public String getAccessibleDescription() { |
| 262 | String description = accessibleDescription; |
| 263 | |
| 264 | // fallback to client property |
| 265 | if (description == null) { |
| 266 | description = (String)getClientProperty(AccessibleContext.ACCESSIBLE_DESCRIPTION_PROPERTY); |
| 267 | } |
| 268 | if (description == null) { |
| 269 | description = getTipText(); |
| 270 | } |
| 271 | return description; |
| 272 | } |
| 273 | |
| 274 | /** |
| 275 | * Get the role of this object. |
| 276 | * |
| 277 | * @return an instance of AccessibleRole describing the role of the |
| 278 | * object |
| 279 | */ |
| 280 | public AccessibleRole getAccessibleRole() { |
| 281 | return AccessibleRole.TOOL_TIP; |
| 282 | } |
| 283 | } |
| 284 | } |