    001/**
    002 * ========================================
    003 * JCommon : a free Java report library
    004 * ========================================
    005 *
    006 * Project Info:  http://www.jfree.org/jcommon/
    007 * Project Lead:  Thomas Morgner;
    008 *
    009 * (C) Copyright 2000-2006, by Object Refinery Limited and Contributors.
    010 *
    011 * This library is free software; you can redistribute it and/or modify it under the terms
    012 * of the GNU Lesser General Public License as published by the Free Software Foundation;
    013 * either version 2.1 of the License, or (at your option) any later version.
    014 *
    015 * This library is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY;
    016 * without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
    017 * See the GNU Lesser General Public License for more details.
    018 *
    019 * You should have received a copy of the GNU Lesser General Public License along with this
    020 * library; if not, write to the Free Software Foundation, Inc., 59 Temple Place, Suite 330,
    021 * Boston, MA 02111-1307, USA.
    022 *
    023 * [Java is a trademark or registered trademark of Sun Microsystems, Inc.
    024 * in the United States and other countries.]
    025 *
    026 * ------------
    027 * DrawablePanel.java
    028 * ------------
    029 * (C) Copyright 2002-2006, by Object Refinery Limited.
    030 *
    031 * Original Author:  Thomas Morgner;
    032 * Contributor(s):   -;
    033 *
    034 * $Id: DrawablePanel.java,v 1.4 2008/09/10 09:25:09 mungady Exp $
    035 *
    036 * Changes
    037 * -------
    038 *
    039 *
    040 */
    041package org.jfree.ui;
    042
    043import java.awt.Dimension;
    044import java.awt.Graphics;
    045import java.awt.Graphics2D;
    046import java.awt.geom.Rectangle2D;
    047import javax.swing.JPanel;
    048
    049/**
    050 * A component, that accepts a drawable and which draws that drawable.
    051 *
    052 * @author Thomas Morgner
    053 */
    054public class DrawablePanel extends JPanel
    055{
    056  private Drawable drawable;
    057
    058  /**
    059   * Creates a new instance.
    060   */
    061  public DrawablePanel()
    062  {
    063    setOpaque(false);
    064  }
    065
    066  /**
    067   * Returns the drawable item.
    068   *
    069   * @return The drawable item.
    070   */
    071  public Drawable getDrawable()
    072  {
    073    return this.drawable;
    074  }
    075
    076  /**
    077   * Sets the drawable item.
    078   *
    079   * @param drawable  the drawable item.
    080   */
    081  public void setDrawable(final Drawable drawable)
    082  {
    083    this.drawable = drawable;
    084    revalidate();
    085    repaint();
    086  }
    087
    088  /**
    089   * If the <code>preferredSize</code> has been set to a non-<code>null</code>
    090   * value just returns it. If the UI delegate's <code>getPreferredSize</code>
    091   * method returns a non <code>null</code> value then return that; otherwise
    092   * defer to the component's layout manager.
    093   *
    094   * @return the value of the <code>preferredSize</code> property
    095   * @see #setPreferredSize
    096   * @see javax.swing.plaf.ComponentUI
    097   */
    098  public Dimension getPreferredSize()
    099  {
    100    if (this.drawable instanceof ExtendedDrawable)
    101    {
    102      final ExtendedDrawable ed = (ExtendedDrawable) this.drawable;
    103      return ed.getPreferredSize();
    104    }
    105    return super.getPreferredSize();
    106  }
    107
    108  /**
    109   * If the minimum size has been set to a non-<code>null</code> value just
    110   * returns it.  If the UI delegate's <code>getMinimumSize</code> method
    111   * returns a non-<code>null</code> value then return that; otherwise defer to
    112   * the component's layout manager.
    113   *
    114   * @return the value of the <code>minimumSize</code> property
    115   * @see #setMinimumSize
    116   * @see javax.swing.plaf.ComponentUI
    117   */
    118  public Dimension getMinimumSize()
    119  {
    120    if (this.drawable instanceof ExtendedDrawable)
    121    {
    122      final ExtendedDrawable ed = (ExtendedDrawable) this.drawable;
    123      return ed.getPreferredSize();
    124    }
    125    return super.getMinimumSize();
    126  }
    127
    128  /**
    129   * Returns true if this component is completely opaque.
    130   * <p/>
    131   * An opaque component paints every pixel within its rectangular bounds. A
    132   * non-opaque component paints only a subset of its pixels or none at all,
    133   * allowing the pixels underneath it to "show through".  Therefore, a
    134   * component that does not fully paint its pixels provides a degree of
    135   * transparency.
    136   * <p/>
    137   * Subclasses that guarantee to always completely paint their contents should
    138   * override this method and return true.
    139   *
    140   * @return true if this component is completely opaque
    141   * @see #setOpaque
    142   */
    143  public boolean isOpaque()
    144  {
    145    if (this.drawable == null)
    146    {
    147      return false;
    148    }
    149    return super.isOpaque();
    150  }
    151
    152  /**
    153   * Calls the UI delegate's paint method, if the UI delegate is
    154   * non-<code>null</code>.  We pass the delegate a copy of the
    155   * <code>Graphics</code> object to protect the rest of the paint code from
    156   * irrevocable changes (for example, <code>Graphics.translate</code>).
    157   * <p/>
    158   * If you override this in a subclass you should not make permanent changes to
    159   * the passed in <code>Graphics</code>. For example, you should not alter the
    160   * clip <code>Rectangle</code> or modify the transform. If you need to do
    161   * these operations you may find it easier to create a new
    162   * <code>Graphics</code> from the passed in <code>Graphics</code> and
    163   * manipulate it. Further, if you do not invoker super's implementation you
    164   * must honor the opaque property, that is if this component is opaque, you
    165   * must completely fill in the background in a non-opaque color. If you do not
    166   * honor the opaque property you will likely see visual artifacts.
    167   * <p/>
    168   * The passed in <code>Graphics</code> object might have a transform other
    169   * than the identify transform installed on it.  In this case, you might get
    170   * unexpected results if you cumulatively apply another transform.
    171   *
    172   * @param g the <code>Graphics</code> object to protect
    173   * @see #paint
    174   * @see javax.swing.plaf.ComponentUI
    175   */
    176  protected void paintComponent(Graphics g)
    177  {
    178    super.paintComponent(g);
    179    if (this.drawable == null)
    180    {
    181      return;
    182    }
    183
    184    final Graphics2D g2 = (Graphics2D) g.create
    185            (0, 0, getWidth(), getHeight());
    186
    187    this.drawable.draw(g2, new Rectangle2D.Double(0, 0, getWidth(), getHeight()));
    188    g2.dispose();
    189  }
    190
    191}