libjava/javax/swing/plaf/TextUI.java

   1 /* TextUI.java --
   2    Copyright (C) 2002, 2003, 2004  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., 59 Temple Place, Suite 330, Boston, MA
  19 02111-1307 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.plaf;
  40
  41 import java.awt.Point;
  42 import java.awt.Rectangle;
  43
  44 import javax.swing.text.BadLocationException;
  45 import javax.swing.text.EditorKit;
  46 import javax.swing.text.JTextComponent;
  47 import javax.swing.text.Position;
  48 import javax.swing.text.View;
  49
  50 /**
  51  * An abstract base class for delegates that provide the user
  52  * interface for text editors.
  53  *
  54  * @see javax.swing.text.JTextComponent
  55  *
  56  * @author Ronald Veldema (rveldema@cs.vu.nl)
  57  * @author Sascha Brawer (brawer@dandelis.ch)
  58  */
  59 public abstract class TextUI
  60   extends ComponentUI
  61 {
  62   /**
  63    * Constructs a new <code>TextUI</code>.
  64    */
  65   public TextUI()
  66   {
  67   }
  68
  69
  70   /**
  71    * Calculates the geometric extent of the character at the
  72    * given offset.
  73    *
  74    * @param tc the <code>JTextComponent</code> for which this
  75    *        delegate object provides the user interface.
  76    *
  77    * @param pos the zero-based index of the character into the
  78    *        document model.
  79    *
  80    * @return the bounding box of the character at index
  81    *         <code>pos</code>, in view coordinates.
  82    *
  83    * @throws BadLocationException if <code>pos</code> does not
  84    *         designate a valid position in the document model.
  85    *
  86    * @see javax.swing.text.View#modelToView(int,
  87    *      javax.swing.text.Position.Bias, int,
  88    *      javax.swing.text.position.Bias, java.awt.Shape)
  89    */
  90   public abstract Rectangle modelToView(JTextComponent tc, int pos)
  91     throws BadLocationException;
  92
  93
  94   /**
  95    * Calculates the geometric extent of the character at the
  96    * given offset.
  97    *
  98    * @param tc the <code>JTextComponent</code> for which this
  99    *        delegate object provides the user interface.
 100    *
 101    * @param pos the zero-based index of the character into the
 102    *        document model.
 103    *
 104    * @param bias whether to take the character before or after the
 105    *        caret position indicated by <code>pos</code>.  The value
 106    *        must be either {@link
 107    *        javax.swing.text.Position.Bias#Backward} or {@link
 108    *        javax.swing.text.Position.Bias#Forward}.
 109    *
 110    * @return the bounding box of the character at index
 111    *         <code>pos</code>, in view coordinates.
 112    *
 113    * @throws BadLocationException if <code>pos</code> does not
 114    *         designate a valid position in the document model.
 115    *
 116    * @see javax.swing.text.View#modelToView(int,
 117    *      javax.swing.text.Position.Bias, int,
 118    *      javax.swing.text.position.Bias, java.awt.Shape)
 119    */
 120   public abstract Rectangle modelToView(JTextComponent tc, int pos,
 121                                         Position.Bias bias)
 122     throws BadLocationException;
 123
 124
 125   /**
 126    * Finds the caret position which is closest to the specified visual
 127    * location.
 128    *
 129    * @param tc the <code>JTextComponent</code> for which this
 130    *        delegate object provides the user interface.
 131    *
 132    * @param loc the position in view coordinates.
 133    *
 134    * @return the caret position which is closest to <code>loc</code>.
 135    *
 136    * @see #viewToModel(JTextComponent, Point, Position.Bias[])
 137    */
 138   public abstract int viewToModel(JTextComponent t, Point pt);
 139
 140
 141   /**
 142    * Finds the caret position which is closest to the specified visual
 143    * location.
 144    *
 145    * @param tc the <code>JTextComponent</code> for which this
 146    *        delegate object provides the user interface.
 147    *
 148    * @param loc the position in view coordinates.
 149    *
 150    * @param outBias an array whose size must be at least one.
 151    *        After the call, <code>outBias[0]</code> will indicate
 152    *        whether <code>loc</code> is in the glyph before
 153    *        (<code>Position.Bias.Backward</code>) or after
 154    *        (<code>Position.Bias.Forward</code>) the returned
 155    *        caret position.
 156    *
 157    * @return the caret position which is closest to <code>loc</code>.
 158    */
 159   public abstract int viewToModel(JTextComponent tc, Point loc,
 160                                   Position.Bias[] outBias);
 161
 162
 163
 164   /**
 165    * Calculates the caret position that is visually next to the given
 166    * position. This is useful to determine where to move the caret
 167    * after the user has pressed an arrow key.
 168    *
 169    * @param tc the <code>JTextComponent</code> for which this
 170    *        delegate object provides the user interface.
 171    *
 172    * @param pos the current caret position, a zero-based index
 173    *        into the document model.
 174    *
 175    * @param bias whether to take the character before or after the
 176    *        caret position indicated by <code>pos</code>.  The value
 177    *        must be either {@link
 178    *        javax.swing.text.Position.Bias#Backward} or {@link
 179    *        javax.swing.text.Position.Bias#Forward}.
 180    *
 181    * @param direction the visual direction. Pass
 182    *        {@link javax.swing.SwingConstants#WEST} for the left
 183    *        arrow key, {@link javax.swing.SwingConstants#EAST}
 184    *        for the right arrow key, {@link
 185    *        javax.swing.SwingConstants#NORTH} for the up arrow
 186    *        key, or {@link javax.swing.SwingConstants#SOUTH}
 187    *        for the down arrow key.
 188    *
 189    * @throws BadLocationException if <code>pos</code> does not
 190    *         designate a valid position in the document model.
 191    *
 192    * @throws IllegalArgumentException if <code>direction</code>
 193    *         is not one of <code>Position.Bias.Forward</code>
 194    *         or <code>Position.Biad.Backward</code>.
 195    */
 196   public abstract int getNextVisualPositionFrom(JTextComponent tc,
 197                                                 int pos,
 198                                                 Position.Bias bias,
 199                                                 int direction,
 200                                                 Position.Bias[] outBias)
 201     throws BadLocationException;
 202
 203
 204   /**
 205    * Repaints a range of characters.
 206    *
 207    * @param tc the <code>JTextComponent</code> for which this
 208    *        delegate object provides the user interface.
 209    *
 210    * @param start the first character in the range that needs
 211    *        painting, indicated as an index into the document model.
 212    *
 213    * @param end the last character in the range that needs
 214    *        painting, indicated as an index into the document model.
 215    *        <code>end</code> must be greater than or equal to
 216    *        <code>start</code>.
 217    */
 218   public abstract void damageRange(JTextComponent tc, int start, int end);
 219
 220
 221   /**
 222    * Repaints a range of characters, also specifying the bias for the
 223    * start and end of the range.
 224    *
 225    * @param tc the <code>JTextComponent</code> for which this
 226    *        delegate object provides the user interface.
 227    *
 228    * @param start the first character in the range that needs
 229    *        painting, indicated as an index into the document model.
 230    *
 231    * @param end the last character in the range that needs
 232    *        painting, indicated as an index into the document model.
 233    *        <code>end</code> must be greater than or equal to
 234    *        <code>start</code>.
 235    */
 236   public abstract void damageRange(JTextComponent tc,
 237                                    int start, int end,
 238                                    Position.Bias startBias,
 239                                    Position.Bias endBias);
 240
 241
 242   /**
 243    * Retrieves the <code>EditorKit</code> managing policies and
 244    * persistent state.
 245    *
 246    * @param tc the <code>JTextComponent</code> for which this
 247    *        delegate object provides the user interface.
 248    *
 249    * @return the <code>EditorKit</code> used by <code>tc</code>.
 250    */
 251   public abstract EditorKit getEditorKit(JTextComponent tc);
 252
 253
 254   /**
 255    * Retrieves the root of the view tree that visually presents
 256    * the text.
 257    *
 258    * @param tc the <code>JTextComponent</code> for which this
 259    *        delegate object provides the user interface.
 260    *
 261    * @return the root <code>View</code> used by <code>tc</code>.
 262    */
 263   public abstract View getRootView(JTextComponent tc);
 264
 265
 266   /**
 267    * Returns a String for presenting a tool tip at the specified
 268    * location.
 269    *
 270    * @param tc the <code>JTextComponent</code> for which this
 271    *        delegate object provides the user interface.
 272    *
 273    * @param loc the location for which the tool tip is requested.
 274    *
 275    * @return the text for the tool tip, or <code>null</code> to
 276    *         display no tool tip.
 277    *
 278    * @since 1.4
 279    */
 280   public String getToolTipText(JTextComponent tc, Point loc)
 281   {
 282     return null;
 283   }
 284 }