001    /* TextUI.java --
002       Copyright (C) 2002, 2003, 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.plaf;
040    
041    import java.awt.Point;
042    import java.awt.Rectangle;
043    import java.awt.Shape;
044    
045    import javax.swing.text.BadLocationException;
046    import javax.swing.text.EditorKit;
047    import javax.swing.text.JTextComponent;
048    import javax.swing.text.Position;
049    import javax.swing.text.View;
050    
051    /**
052     * An abstract base class for delegates that provide the user
053     * interface for text editors.
054     *
055     * @see javax.swing.text.JTextComponent
056     *
057     * @author Ronald Veldema (rveldema@cs.vu.nl)
058     * @author Sascha Brawer (brawer@dandelis.ch)
059     */
060    public abstract class TextUI extends ComponentUI
061    {
062      /**
063       * Constructs a new <code>TextUI</code>.
064       */  
065      public TextUI()
066      {
067        // Nothing to do here.
068      }
069    
070    
071      /**
072       * Calculates the geometric extent of the character at the
073       * given offset.
074       *
075       * @param tc the <code>JTextComponent</code> for which this
076       *        delegate object provides the user interface.
077       *
078       * @param pos the zero-based index of the character into the
079       *        document model.
080       *
081       * @return the bounding box of the character at index
082       *         <code>pos</code>, in view coordinates.
083       *
084       * @throws BadLocationException if <code>pos</code> does not
085       *         designate a valid position in the document model.
086       *
087       * @see javax.swing.text.ComponentView#modelToView(int, Shape, Position.Bias)
088       */
089      public abstract Rectangle modelToView(JTextComponent tc, int pos)
090        throws BadLocationException;
091    
092    
093      /**
094       * Calculates the geometric extent of the character at the
095       * given offset.
096       *
097       * @param tc the <code>JTextComponent</code> for which this
098       *        delegate object provides the user interface.
099       *
100       * @param pos the zero-based index of the character into the
101       *        document model.
102       *
103       * @param bias whether to take the character before or after the
104       *        caret position indicated by <code>pos</code>.  The value
105       *        must be either {@link
106       *        javax.swing.text.Position.Bias#Backward} or {@link
107       *        javax.swing.text.Position.Bias#Forward}.
108       *
109       * @return the bounding box of the character at index
110       *         <code>pos</code>, in view coordinates.
111       *
112       * @throws BadLocationException if <code>pos</code> does not
113       *         designate a valid position in the document model.
114       *
115       * @see javax.swing.text.ComponentView#modelToView(int, Shape, Position.Bias)
116       */
117      public abstract Rectangle modelToView(JTextComponent tc, int pos,
118                                            Position.Bias bias)
119        throws BadLocationException;
120    
121    
122      /**
123       * Finds the caret position which is closest to the specified visual
124       * location.
125       *
126       * @param t the <code>JTextComponent</code> for which this
127       *        delegate object provides the user interface.
128       *
129       * @param pt the position in view coordinates.
130       *
131       * @return the caret position which is closest to <code>loc</code>.
132       *
133       * @see #viewToModel(JTextComponent, Point, Position.Bias[])
134       */
135      public abstract int viewToModel(JTextComponent t, Point pt);
136    
137    
138      /**
139       * Finds the caret position which is closest to the specified visual
140       * location.
141       *
142       * @param tc the <code>JTextComponent</code> for which this
143       *        delegate object provides the user interface.
144       *
145       * @param loc the position in view coordinates.
146       *
147       * @param outBias an array whose size must be at least one.
148       *        After the call, <code>outBias[0]</code> will indicate
149       *        whether <code>loc</code> is in the glyph before
150       *        (<code>Position.Bias.Backward</code>) or after
151       *        (<code>Position.Bias.Forward</code>) the returned
152       *        caret position.
153       *
154       * @return the caret position which is closest to <code>loc</code>.
155       */
156      public abstract int viewToModel(JTextComponent tc, Point loc,
157                                      Position.Bias[] outBias);
158     
159    
160    
161      /**
162       * Calculates the caret position that is visually next to the given
163       * position. This is useful to determine where to move the caret
164       * after the user has pressed an arrow key.
165       *
166       * @param tc the <code>JTextComponent</code> for which this
167       *        delegate object provides the user interface.
168       *
169       * @param pos the current caret position, a zero-based index
170       *        into the document model.
171       *
172       * @param bias whether to take the character before or after the
173       *        caret position indicated by <code>pos</code>.  The value
174       *        must be either {@link
175       *        javax.swing.text.Position.Bias#Backward} or {@link
176       *        javax.swing.text.Position.Bias#Forward}.
177       *
178       * @param direction the visual direction. Pass
179       *        {@link javax.swing.SwingConstants#WEST} for the left
180       *        arrow key, {@link javax.swing.SwingConstants#EAST}
181       *        for the right arrow key, {@link
182       *        javax.swing.SwingConstants#NORTH} for the up arrow
183       *        key, or {@link javax.swing.SwingConstants#SOUTH}
184       *        for the down arrow key.
185       *
186       * @throws BadLocationException if <code>pos</code> does not
187       *         designate a valid position in the document model.
188       *
189       * @throws IllegalArgumentException if <code>direction</code>
190       *         is not one of <code>Position.Bias.Forward</code>
191       *         or <code>Position.Bias.Backward</code>.
192       */
193      public abstract int getNextVisualPositionFrom(JTextComponent tc,
194                                                    int pos,
195                                                    Position.Bias bias,
196                                                    int direction,
197                                                    Position.Bias[] outBias)
198        throws BadLocationException;
199    
200    
201      /**
202       * Repaints a range of characters.
203       *
204       * @param tc the <code>JTextComponent</code> for which this
205       *        delegate object provides the user interface.
206       *
207       * @param start the first character in the range that needs
208       *        painting, indicated as an index into the document model.
209       *
210       * @param end the last character in the range that needs
211       *        painting, indicated as an index into the document model.
212       *        <code>end</code> must be greater than or equal to
213       *        <code>start</code>.
214       */
215      public abstract void damageRange(JTextComponent tc, int start, int end);
216    
217    
218      /**
219       * Repaints a range of characters, also specifying the bias for the
220       * start and end of the range.
221       *
222       * @param tc the <code>JTextComponent</code> for which this
223       *        delegate object provides the user interface.
224       *
225       * @param start the first character in the range that needs
226       *        painting, indicated as an index into the document model.
227       *
228       * @param end the last character in the range that needs
229       *        painting, indicated as an index into the document model.
230       *        <code>end</code> must be greater than or equal to
231       *        <code>start</code>.
232       */
233      public abstract void damageRange(JTextComponent tc,
234                                       int start, int end,
235                                       Position.Bias startBias,
236                                       Position.Bias endBias);
237    
238      
239      /**
240       * Retrieves the <code>EditorKit</code> managing policies and
241       * persistent state.
242       *
243       * @param tc the <code>JTextComponent</code> for which this
244       *        delegate object provides the user interface.
245       *
246       * @return the <code>EditorKit</code> used by <code>tc</code>.
247       */
248      public abstract EditorKit getEditorKit(JTextComponent tc);
249      
250      
251      /**
252       * Retrieves the root of the view tree that visually presents
253       * the text.
254       *
255       * @param tc the <code>JTextComponent</code> for which this
256       *        delegate object provides the user interface.
257       *
258       * @return the root <code>View</code> used by <code>tc</code>.
259       */
260      public abstract View getRootView(JTextComponent tc);
261    
262    
263      /**
264       * Returns a String for presenting a tool tip at the specified
265       * location.
266       *
267       * @param tc the <code>JTextComponent</code> for which this
268       *        delegate object provides the user interface.
269       *
270       * @param loc the location for which the tool tip is requested.
271       *
272       * @return the text for the tool tip, or <code>null</code> to
273       *         display no tool tip.
274       *
275       * @since 1.4
276       */
277      public String getToolTipText(JTextComponent tc, Point loc)
278      {
279        return null;
280      }
281    }