001 /* IconView.java -- A view to render icons
002 Copyright (C) 2005 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.text;
040
041 import java.awt.Graphics;
042 import java.awt.Rectangle;
043 import java.awt.Shape;
044
045 import javax.swing.Icon;
046 import javax.swing.JTextPane;
047
048 /**
049 * A View that can render an icon. This view is created by the
050 * {@link StyledEditorKit}'s view factory for all elements that have name
051 * {@link StyleConstants#IconElementName}. This is usually created by
052 * inserting an icon into <code>JTextPane</code> using
053 * {@link JTextPane#insertIcon(Icon)}
054 *
055 * The icon is determined using the attribute
056 * {@link StyleConstants#IconAttribute}, which's value must be an {@link Icon}.
057 *
058 * @author Roman Kennke (kennke@aicas.com)
059 */
060 public class IconView
061 extends View
062 {
063
064 /**
065 * Creates a new <code>IconView</code> for the given <code>Element</code>.
066 *
067 * @param element the element that is rendered by this IconView
068 */
069 public IconView(Element element)
070 {
071 super(element);
072 }
073
074 /**
075 * Renders the <code>Element</code> that is associated with this
076 * <code>View</code>.
077 *
078 * @param g the <code>Graphics</code> context to render to
079 * @param a the allocated region for the <code>Element</code>
080 */
081 public void paint(Graphics g, Shape a)
082 {
083 Icon icon = StyleConstants.getIcon(getElement().getAttributes());
084 Rectangle b = a.getBounds();
085 icon.paintIcon(getContainer(), g, b.x, b.y);
086 }
087
088 /**
089 * Returns the preferred span of the content managed by this
090 * <code>View</code> along the specified <code>axis</code>.
091 *
092 * @param axis the axis
093 *
094 * @return the preferred span of this <code>View</code>.
095 */
096 public float getPreferredSpan(int axis)
097 {
098 Icon icon = StyleConstants.getIcon(getElement().getAttributes());
099 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 }