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 gnu.java.lang.CPStringBuilder;
042
043 import java.awt.AWTEvent;
044 import java.beans.PropertyChangeEvent;
045
046 import javax.accessibility.Accessible;
047 import javax.accessibility.AccessibleContext;
048 import javax.accessibility.AccessibleRole;
049 import javax.swing.plaf.ToolTipUI;
050
051 /**
052 * This class is used to display ToolTips. ToolTips are small floating windows
053 * that display text when the mouse comes to rest over a Component. ToolTips
054 * are set for JComponents using JComponent.setToolTipText(String).
055 */
056 public class JToolTip extends JComponent implements Accessible
057 {
058
059 private static final long serialVersionUID = -1138929898906751643L;
060
061 /**
062 * Provides the accessibility features for the <code>JToolTip</code>
063 * component.
064 */
065 protected class AccessibleJToolTip extends AccessibleJComponent
066 {
067 private static final long serialVersionUID = -6222548177795408476L;
068
069 /**
070 * Creates a new AccessibleJToolTip object.
071 */
072 protected AccessibleJToolTip()
073 {
074 // Nothing to do here.
075 }
076
077 /**
078 * Returns a description for the accessible component.
079 *
080 * @return A description for the accessible component.
081 */
082 public String getAccessibleDescription()
083 {
084 String result = super.getAccessibleDescription();
085 if (result == null)
086 result = text;
087 return result;
088 }
089
090 /**
091 * Returns the accessible role for the <code>JToolTip</code> component.
092 *
093 * @return {@link AccessibleRole#TOOL_TIP}.
094 */
095 public AccessibleRole getAccessibleRole()
096 {
097 return AccessibleRole.TOOL_TIP;
098 }
099 }
100
101 /** The text to display in the JToolTip. */
102 String text;
103
104 /** The component that the tool tip is associated with. */
105 JComponent component;
106
107 /**
108 * Creates a new <code>JToolTip</code> instance.
109 */
110 public JToolTip()
111 {
112 disableEvents(AWTEvent.MOUSE_EVENT_MASK);
113 updateUI();
114 }
115
116 /**
117 * Returns the text displayed by the tool tip.
118 *
119 * @return The text (possibly <code>null</code>).
120 *
121 * @see #setTipText(String)
122 */
123 public String getTipText()
124 {
125 return text;
126 }
127
128 /**
129 * Returns the object that provides accessibility features for this
130 * <code>JToolTip</code> component.
131 *
132 * @return The accessible context (an instance of {@link AccessibleJToolTip}).
133 */
134 public AccessibleContext getAccessibleContext()
135 {
136 if (accessibleContext == null)
137 accessibleContext = new AccessibleJToolTip();
138 return accessibleContext;
139 }
140
141 /**
142 * Returns the component that the tool tip is associated with.
143 *
144 * @return The component (possibly <code>null</code>).
145 *
146 * @see #setComponent(JComponent)
147 */
148 public JComponent getComponent()
149 {
150 return component;
151 }
152
153 /**
154 * Returns the current UI delegate for this component.
155 *
156 * @return The UI delegate.
157 */
158 public ToolTipUI getUI()
159 {
160 return (ToolTipUI) ui;
161 }
162
163 /**
164 * Returns the string suffix used to identify the UI class, in this case
165 * <code>"ToolTipUI"</code>.
166 *
167 * @return <code>"ToolTipUI"</code>.
168 */
169 public String getUIClassID()
170 {
171 return "ToolTipUI";
172 }
173
174 /**
175 * Returns a string describing the attributes for the <code>JToolTip</code>
176 * component, for use in debugging. The return value is guaranteed to be
177 * non-<code>null</code>, but the format of the string may vary between
178 * implementations.
179 *
180 * @return A string describing the attributes of the <code>JToolTip</code>.
181 */
182 protected String paramString()
183 {
184 CPStringBuilder sb = new CPStringBuilder(super.paramString());
185 sb.append(",tiptext=");
186 if (text != null)
187 sb.append(text);
188 return sb.toString();
189 }
190
191 /**
192 * Sets the component that the tool tip is associated with and sends a
193 * {@link PropertyChangeEvent} (with the property name 'component') to all
194 * registered listeners.
195 *
196 * @param c the component (<code>null</code> permitted).
197 *
198 * @see #getComponent()
199 */
200 public void setComponent(JComponent c)
201 {
202 JComponent oldValue = component;
203 component = c;
204 firePropertyChange("component", oldValue, c);
205 }
206
207 /**
208 * Sets the text to be displayed by the tool tip and sends a
209 * {@link PropertyChangeEvent} (with the property name 'tiptext') to all
210 * registered listeners.
211 *
212 * @param tipText the text (<code>null</code> permitted).
213 *
214 * @see #getTipText()
215 */
216 public void setTipText(String tipText)
217 {
218 String oldValue = text;
219 text = tipText;
220 firePropertyChange("tiptext", oldValue, tipText);
221 }
222
223 /**
224 * This method resets the UI used to the Look and Feel default.
225 */
226 public void updateUI()
227 {
228 setUI((ToolTipUI) UIManager.getUI(this));
229 }
230
231 /**
232 * Returns <code>true</code> if the component is guaranteed to be painted
233 * on top of others. This returns false by default and is overridden by
234 * components like JMenuItem, JPopupMenu and JToolTip to return true for
235 * added efficiency.
236 *
237 * @return <code>true</code> if the component is guaranteed to be painted
238 * on top of others
239 */
240 boolean onTop()
241 {
242 return true;
243 }
244 }