imagerenderfunction.java

swing编写的库存管理程序。毕业设计类

/**
 * ========================================
 * JFreeReport : a free Java report library
 * ========================================
 *
 * Project Info:  http://www.jfree.org/jfreereport/index.html
 * Project Lead:  Thomas Morgner;
 *
 * (C) Copyright 2000-2002, by Simba Management Limited and Contributors.
 *
 * This library is free software; you can redistribute it and/or modify it under the terms
 * of the GNU Lesser General Public License as published by the Free Software Foundation;
 * either version 2.1 of the License, or (at your option) any later version.
 *
 * This library is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY;
 * without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
 * See the GNU Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public License along with this
 * library; if not, write to the Free Software Foundation, Inc., 59 Temple Place, Suite 330,
 * Boston, MA 02111-1307, USA.
 *
 * -----------------------
 * ImageRenderFunction.java
 * -----------------------
 * (C)opyright 2000-2002, by Simba Management Limited.
 *
 * $Id: ImageRenderFunction.java,v 1.3 2003/08/25 14:29:28 taqua Exp $
 *
 * ChangeLog
 * ---------
 * 14-Aug-2002 : Initial version
 * 22-Aug-2002 : Removed System.out statements
 * 28-Aug-2002 : Documentation
 */
package org.jfree.report.demo.helper;

import java.awt.Color;
import java.awt.Font;
import java.awt.Graphics2D;
import java.awt.geom.AffineTransform;
import java.awt.image.BufferedImage;
import java.io.Serializable;
import javax.swing.JButton;
import javax.swing.JRadioButton;

import org.jfree.report.ImageReference;
import org.jfree.report.event.PageEventListener;
import org.jfree.report.event.ReportEvent;
import org.jfree.report.function.AbstractFunction;

/**
 * The ImageRenderFunction creates a simple Image using a BufferedImage within a function to show
 * the use of the ImageFunctionElement. The image is created whenever a new page is started.
 *
 * @author Thomas Morgner
 */
public class ImageRenderFunction extends AbstractFunction
    implements Serializable, PageEventListener
{
  /** The function value. */
  private transient ImageReference functionValue;

  /**
   * Create a image according to the current state, simple and silly ...
   *
   * @param event  the report event.
   */
  public void pageStarted(final ReportEvent event)
  {
    final BufferedImage image = new BufferedImage(150, 50, BufferedImage.TYPE_INT_ARGB);
    final Graphics2D g2 = image.createGraphics();
    final JButton bt = new JButton("A Button");
    bt.setSize(90, 20);
    final JRadioButton radio = new JRadioButton("A radio button");
    radio.setSize(100, 20);

    g2.setColor(Color.darkGray);
    bt.paint(g2);
    g2.setColor(Color.blue);
    g2.setTransform(AffineTransform.getTranslateInstance(20, 20));
    radio.paint(g2);
    g2.setTransform(AffineTransform.getTranslateInstance(0, 0));
    g2.setPaint(Color.green);
    g2.setFont(new Font("Serif", Font.PLAIN, 10));
    g2.drawString("You are viewing a graphics of JFreeReport on index "
        + event.getState().getCurrentDisplayItem(), 10, 10);

    functionValue = new ImageReference(image);
  }

  /**
   * Receives notification that a page is completed.
   *
   * @param event The event.
   */
  public void pageFinished(final ReportEvent event)
  {
  }

  /**
   * Return the last generated Image.
   *
   * @return the function value.
   */
  public Object getValue()
  {
    return functionValue;
  }


  /**
   * Receives notification that a page was canceled by the ReportProcessor.
   * This method is called, when a page was removed from the report after
   * it was generated.
   *
   * @param event The event.
   */
  public void pageCanceled(final ReportEvent event)
  {
    functionValue = null;
  }

}