Source for org.jfree.ui.ArrowPanel

   1: /* ========================================================================
   2:  * JCommon : a free general purpose class library for the Java(tm) platform
   3:  * ========================================================================
   4:  *
   5:  * (C) Copyright 2000-2005, by Object Refinery Limited and Contributors.
   6:  * 
   7:  * Project Info:  http://www.jfree.org/jcommon/index.html
   8:  *
   9:  * This library is free software; you can redistribute it and/or modify it 
  10:  * under the terms of the GNU Lesser General Public License as published by 
  11:  * the Free Software Foundation; either version 2.1 of the License, or 
  12:  * (at your option) any later version.
  13:  *
  14:  * This library is distributed in the hope that it will be useful, but 
  15:  * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY 
  16:  * or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public 
  17:  * License for more details.
  18:  *
  19:  * You should have received a copy of the GNU Lesser General Public
  20:  * License along with this library; if not, write to the Free Software
  21:  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, 
  22:  * USA.  
  23:  *
  24:  * [Java is a trademark or registered trademark of Sun Microsystems, Inc. 
  25:  * in the United States and other countries.]
  26:  * 
  27:  * ---------------
  28:  * ArrowPanel.java
  29:  * ---------------
  30:  * (C) Copyright 2002-2004, by Object Refinery Limited.
  31:  *
  32:  * Original Author:  David Gilbert (for Object Refinery Limited);
  33:  * Contributor(s):   -;
  34:  *
  35:  * $Id: ArrowPanel.java,v 1.5 2005/11/16 15:58:41 taqua Exp $
  36:  *
  37:  * Changes
  38:  * -------
  39:  * 25-Sep-2002 : Version 1 (DG);
  40:  * 13-Oct-2002 : Added Javadocs (DG);
  41:  *
  42:  */
  43: 
  44: package org.jfree.ui;
  45: 
  46: import java.awt.Dimension;
  47: import java.awt.Graphics;
  48: import java.awt.Graphics2D;
  49: import java.awt.Insets;
  50: import java.awt.Polygon;
  51: import java.awt.Shape;
  52: import java.awt.geom.Rectangle2D;
  53: 
  54: import javax.swing.JPanel;
  55: 
  56: /**
  57:  * A basic panel that displays a small up or down arrow.
  58:  *
  59:  * @author David Gilbert
  60:  */
  61: public class ArrowPanel extends JPanel {
  62: 
  63:     /** A constant for the up arrow. */
  64:     public static final int UP = 0;
  65: 
  66:     /** A constant for the down arrow. */
  67:     public static final int DOWN = 1;
  68: 
  69:     /** The arrow type. */
  70:     private int type = UP;
  71: 
  72:     /** The available area. */
  73:     private Rectangle2D available = new Rectangle2D.Float();
  74: 
  75:     /**
  76:      * Creates a new arrow panel.
  77:      *
  78:      * @param type  the arrow type.
  79:      */
  80:     public ArrowPanel(final int type) {
  81:         this.type = type;
  82:         setPreferredSize(new Dimension(14, 9));
  83:     }
  84: 
  85:     /**
  86:      * Paints the arrow panel.
  87:      *
  88:      * @param g  the graphics device for drawing on.
  89:      */
  90:     public void paintComponent(final Graphics g) {
  91: 
  92:         super.paintComponent(g);
  93:         final Graphics2D g2 = (Graphics2D) g;
  94: 
  95:         // first determine the size of the drawing area...
  96:         final Dimension size = getSize();
  97:         final Insets insets = getInsets();
  98:         this.available.setRect(insets.left, insets.top,
  99:                                size.getWidth() - insets.left - insets.right,
 100:                                size.getHeight() - insets.top - insets.bottom);
 101:         g2.translate(insets.left, insets.top);
 102:         g2.fill(getArrow(this.type));
 103: 
 104:     }
 105: 
 106:     /**
 107:      * Returns a shape for the arrow.
 108:      *
 109:      * @param t  the arrow type.
 110:      *
 111:      * @return the arrow shape.
 112:      */
 113:     private Shape getArrow(final int t) {
 114:         switch (t) {
 115:             case UP : return getUpArrow();
 116:             case DOWN : return getDownArrow();
 117:             default : return getUpArrow();
 118:         }
 119:     }
 120: 
 121:     /**
 122:      * Returns an up arrow.
 123:      *
 124:      * @return an up arrow.
 125:      */
 126:     private Shape getUpArrow() {
 127:         final Polygon result = new Polygon();
 128:         result.addPoint(7, 2);
 129:         result.addPoint(2, 7);
 130:         result.addPoint(12, 7);
 131:         return result;
 132:     }
 133: 
 134:     /**
 135:      * Returns a down arrow.
 136:      *
 137:      * @return a down arrow.
 138:      */
 139:     private Shape getDownArrow() {
 140:         final Polygon result = new Polygon();
 141:         result.addPoint(7, 7);
 142:         result.addPoint(2, 2);
 143:         result.addPoint(12, 2);
 144:         return result;
 145:     }
 146: 
 147: }