001 /* JToolTip.java --
002 Copyright (C) 2002, 2004 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;
040
041 import java.awt.AWTEvent;
042 import java.beans.PropertyChangeEvent;
043
044 import javax.accessibility.Accessible;
045 import javax.accessibility.AccessibleContext;
046 import javax.accessibility.AccessibleRole;
047 import javax.swing.plaf.ToolTipUI;
048
049 /**
050 * This class is used to display ToolTips. ToolTips are small floating windows
051 * that display text when the mouse comes to rest over a Component. ToolTips
052 * are set for JComponents using JComponent.setToolTipText(String).
053 */
054 public class JToolTip extends JComponent implements Accessible
055 {
056
057 private static final long serialVersionUID = -1138929898906751643L;
058
059 /**
060 * Provides the accessibility features for the <code>JToolTip</code>
061 * component.
062 */
063 protected class AccessibleJToolTip extends AccessibleJComponent
064 {
065 private static final long serialVersionUID = -6222548177795408476L;
066
067 /**
068 * Creates a new AccessibleJToolTip object.
069 */
070 protected AccessibleJToolTip()
071 {
072 // Nothing to do here.
073 }
074
075 /**
076 * Returns a description for the accessible component.
077 *
078 * @return A description for the accessible component.
079 */
080 public String getAccessibleDescription()
081 {
082 String result = super.getAccessibleDescription();
083 if (result == null)
084 result = text;
085 return result;
086 }
087
088 /**
089 * Returns the accessible role for the <code>JToolTip</code> component.
090 *
091 * @return {@link AccessibleRole#TOOL_TIP}.
092 */
093 public AccessibleRole getAccessibleRole()
094 {
095 return AccessibleRole.TOOL_TIP;
096 }
097 }
098
099 /** The text to display in the JToolTip. */
100 String text;
101
102 /** The component that the tool tip is associated with. */
103 JComponent component;
104
105 /**
106 * Creates a new <code>JToolTip</code> instance.
107 */
108 public JToolTip()
109 {
110 disableEvents(AWTEvent.MOUSE_EVENT_MASK);
111 updateUI();
112 }
113
114 /**
115 * Returns the text displayed by the tool tip.
116 *
117 * @return The text (possibly <code>null</code>).
118 *
119 * @see #setTipText(String)
120 */
121 public String getTipText()
122 {
123 return text;
124 }
125
126 /**
127 * Returns the object that provides accessibility features for this
128 * <code>JToolTip</code> component.
129 *
130 * @return The accessible context (an instance of {@link AccessibleJToolTip}).
131 */
132 public AccessibleContext getAccessibleContext()
133 {
134 if (accessibleContext == null)
135 accessibleContext = new AccessibleJToolTip();
136 return accessibleContext;
137 }
138
139 /**
140 * Returns the component that the tool tip is associated with.
141 *
142 * @return The component (possibly <code>null</code>).
143 *
144 * @see #setComponent(JComponent)
145 */
146 public JComponent getComponent()
147 {
148 return component;
149 }
150
151 /**
152 * Returns the current UI delegate for this component.
153 *
154 * @return The UI delegate.
155 */
156 public ToolTipUI getUI()
157 {
158 return (ToolTipUI) ui;
159 }
160
161 /**
162 * Returns the string suffix used to identify the UI class, in this case
163 * <code>"ToolTipUI"</code>.
164 *
165 * @return <code>"ToolTipUI"</code>.
166 */
167 public String getUIClassID()
168 {
169 return "ToolTipUI";
170 }
171
172 /**
173 * Returns a string describing the attributes for the <code>JToolTip</code>
174 * component, for use in debugging. The return value is guaranteed to be
175 * non-<code>null</code>, but the format of the string may vary between
176 * implementations.
177 *
178 * @return A string describing the attributes of the <code>JToolTip</code>.
179 */
180 protected String paramString()
181 {
182 StringBuffer sb = new StringBuffer(super.paramString());
183 sb.append(",tiptext=");
184 if (text != null)
185 sb.append(text);
186 return sb.toString();
187 }
188
189 /**
190 * Sets the component that the tool tip is associated with and sends a
191 * {@link PropertyChangeEvent} (with the property name 'component') to all
192 * registered listeners.
193 *
194 * @param c the component (<code>null</code> permitted).
195 *
196 * @see #getComponent()
197 */
198 public void setComponent(JComponent c)
199 {
200 JComponent oldValue = component;
201 component = c;
202 firePropertyChange("component", oldValue, c);
203 }
204
205 /**
206 * Sets the text to be displayed by the tool tip and sends a
207 * {@link PropertyChangeEvent} (with the property name 'tiptext') to all
208 * registered listeners.
209 *
210 * @param tipText the text (<code>null</code> permitted).
211 *
212 * @see #getTipText()
213 */
214 public void setTipText(String tipText)
215 {
216 String oldValue = text;
217 text = tipText;
218 firePropertyChange("tiptext", oldValue, tipText);
219 }
220
221 /**
222 * This method resets the UI used to the Look and Feel default.
223 */
224 public void updateUI()
225 {
226 setUI((ToolTipUI) UIManager.getUI(this));
227 }
228
229 /**
230 * Returns <code>true</code> if the component is guaranteed to be painted
231 * on top of others. This returns false by default and is overridden by
232 * components like JMenuItem, JPopupMenu and JToolTip to return true for
233 * added efficiency.
234 *
235 * @return <code>true</code> if the component is guaranteed to be painted
236 * on top of others
237 */
238 boolean onTop()
239 {
240 return true;
241 }
242 }