Source for javax.swing.text.IconView

   1: /* IconView.java -- A view to render icons
   2:    Copyright (C) 2005  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., 51 Franklin Street, Fifth Floor, Boston, MA
  19: 02110-1301 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.text;
  40: 
  41: import java.awt.Graphics;
  42: import java.awt.Rectangle;
  43: import java.awt.Shape;
  44: 
  45: import javax.swing.Icon;
  46: import javax.swing.JTextPane;
  47: 
  48: /**
  49:  * A View that can render an icon. This view is created by the
  50:  * {@link StyledEditorKit}'s view factory for all elements that have name
  51:  * {@link StyleConstants#IconElementName}. This is usually created by
  52:  * inserting an icon into <code>JTextPane</code> using
  53:  * {@link JTextPane#insertIcon(Icon)}
  54:  *
  55:  * The icon is determined using the attribute
  56:  * {@link StyleConstants#IconAttribute}, which's value must be an {@link Icon}.
  57:  *
  58:  * @author Roman Kennke (kennke@aicas.com)
  59:  */
  60: public class IconView
  61:   extends View
  62: {
  63: 
  64:   /**
  65:    * Creates a new <code>IconView</code> for the given <code>Element</code>.
  66:    *
  67:    * @param element the element that is rendered by this IconView
  68:    */
  69:   public IconView(Element element)
  70:   {
  71:     super(element);
  72:   }
  73: 
  74:   /**
  75:    * Renders the <code>Element</code> that is associated with this
  76:    * <code>View</code>.
  77:    *
  78:    * @param g the <code>Graphics</code> context to render to
  79:    * @param a the allocated region for the <code>Element</code>
  80:    */
  81:   public void paint(Graphics g, Shape a)
  82:   {
  83:     Icon icon = StyleConstants.getIcon(getElement().getAttributes());
  84:     Rectangle b = a.getBounds();
  85:     icon.paintIcon(getContainer(), g, b.x, b.y);
  86:   }
  87: 
  88:   /**
  89:    * Returns the preferred span of the content managed by this
  90:    * <code>View</code> along the specified <code>axis</code>.
  91:    *
  92:    * @param axis the axis
  93:    *
  94:    * @return the preferred span of this <code>View</code>.
  95:    */
  96:   public float getPreferredSpan(int axis)
  97:   {
  98:     Icon icon = StyleConstants.getIcon(getElement().getAttributes());
  99:     float span;
 100:     if (axis == X_AXIS)
 101:       span = icon.getIconWidth();
 102:     else if (axis == Y_AXIS)
 103:       span = icon.getIconHeight();
 104:     else
 105:       throw new IllegalArgumentException();
 106:     return span;
 107:   }
 108: 
 109:   /**
 110:    * Maps a position in the document into the coordinate space of the View.
 111:    * The output rectangle usually reflects the font height but has a width
 112:    * of zero.
 113:    *
 114:    * @param pos the position of the character in the model
 115:    * @param a the area that is occupied by the view
 116:    * @param b either {@link Position.Bias#Forward} or
 117:    *        {@link Position.Bias#Backward} depending on the preferred
 118:    *        direction bias. If <code>null</code> this defaults to
 119:    *        <code>Position.Bias.Forward</code>
 120:    *
 121:    * @return a rectangle that gives the location of the document position
 122:    *         inside the view coordinate space
 123:    *
 124:    * @throws BadLocationException if <code>pos</code> is invalid
 125:    * @throws IllegalArgumentException if b is not one of the above listed
 126:    *         valid values
 127:    */
 128:   public Shape modelToView(int pos, Shape a, Position.Bias b)
 129:     throws BadLocationException
 130:   {
 131:     Element el = getElement();
 132:     Rectangle r = a.getBounds();
 133:     Icon icon = StyleConstants.getIcon(el.getAttributes());
 134:     return new Rectangle(r.x, r.y, icon.getIconWidth(), icon.getIconHeight());
 135:   }
 136: 
 137:   /**
 138:    * Maps coordinates from the <code>View</code>'s space into a position
 139:    * in the document model.
 140:    *
 141:    * @param x the x coordinate in the view space
 142:    * @param y the y coordinate in the view space
 143:    * @param a the allocation of this <code>View</code>
 144:    * @param b the bias to use
 145:    *
 146:    * @return the position in the document that corresponds to the screen
 147:    *         coordinates <code>x, y</code>
 148:    */
 149:   public int viewToModel(float x, float y, Shape a, Position.Bias[] b)
 150:   {
 151:     // The element should only have one character position and it is clear
 152:     // that this position is the position that best matches the given screen
 153:     // coordinates, simply because this view has only this one position.
 154:     Element el = getElement();
 155:     return el.getStartOffset();
 156:   }
 157: 
 158:   /**
 159:    * Returns the alignment for this view. This will be 1.0 for the Y_AXIS,
 160:    * and the super behaviour for the X_AXIS.
 161:    *
 162:    * @param axis the axis for which to calculate the alignment
 163:    *
 164:    * @return the alignment
 165:    */
 166:   public float getAlignment(int axis)
 167:   {
 168:     float align;
 169:     if (axis == Y_AXIS)
 170:       align = 1.0F;
 171:     else
 172:       align = super.getAlignment(axis);
 173:     return align;
 174:   }
 175: }