    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     */
    041    package org.jfree.ui;
    042
    043    import java.awt.Dimension;
    044    import java.awt.Graphics;
    045    import java.awt.Graphics2D;
    046    import java.awt.geom.Rectangle2D;
    047    import javax.swing.JPanel;
    048
    049    /**
    050     * A component, that accepts a drawable and which draws that drawable.
    051     *
    052     * @author Thomas Morgner
    053     */
    054    public 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    }