imagecanvas.java

值得一看的J2ME_J2EE结合使用经典例程

/*
 * Copyright 1999-2002 Sun Microsystems, Inc. ALL RIGHTS RESERVED
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 * - Redistributions of source code must retain the above copyright
 *   notice, this list of conditions and the following disclaimer.
 *
 * - Redistribution in binary form must reproduce the above copyright
 *   notice, this list of conditions and the following disclaimer in
 *   the documentation and/or other materials provided with the
 *   distribution.
 *
 * Neither the name of Sun Microsystems, Inc. or the names of
 * contributors may be used to endorse or promote products derived
 * from this software without specific prior written permission.
 *
 * This software is provided "AS IS," without a warranty of any
 * kind. ALL EXPRESS OR IMPLIED CONDITIONS, REPRESENTATIONS AND
 * WARRANTIES, INCLUDING ANY IMPLIED WARRANTY OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE OR NON-INFRINGEMENT, ARE HEREBY
 * EXCLUDED. SUN AND ITS LICENSORS SHALL NOT BE LIABLE FOR ANY DAMAGES
 * SUFFERED BY LICENSEE AS A RESULT OF USING, MODIFYING OR
 * DISTRIBUTING THE SOFTWARE OR ITS DERIVATIVES. IN NO EVENT WILL SUN
 * OR ITS LICENSORS BE LIABLE FOR ANY LOST REVENUE, PROFIT OR DATA, OR
 * FOR DIRECT, INDIRECT, SPECIAL, CONSEQUENTIAL, INCIDENTAL OR
 * PUNITIVE DAMAGES, HOWEVER CAUSED AND REGARDLESS OF THE THEORY OF
 * LIABILITY, ARISING OUT OF THE USE OF OR INABILITY TO USE SOFTWARE,
 * EVEN IF SUN HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH DAMAGES.
 * 
 * You acknowledge that Software is not designed, licensed or intended
 * for use in the design, construction, operation or maintenance of
 * any nuclear facility.
 */

package st;

import javax.microedition.midlet.*;
import javax.microedition.lcdui.*;
import javax.microedition.io.*;
import java.io.*;

import shared.MessageConstants;

/**
 * Displays an image.
 */
public class ImageCanvas extends Canvas {
    
    Image image;
    
    public ImageCanvas() {}
    
    public ImageCanvas(Image i) {
        image = i;
    }
    
    public void setImage(Image i) { image = i; }
    
    /* Overridden methods */
    
    public void paint(Graphics g) {
        g.setColor(0xffffff);  // Set color to white
        g.fillRect(0, 0, getWidth(), getHeight());
        if (image != null) {
            g.drawImage(image, 
			(getWidth() - image.getWidth()) / 2, 
			(getHeight() - image.getHeight()) / 2,
			Graphics.TOP | Graphics.LEFT);
        } else {
            g.drawString(SmartTicket.getMsg(MessageConstants.NO_IMAGE), 
			 0, 0, Graphics.TOP | Graphics.LEFT);
        }
    }
    
    protected void showNotify() { repaint(); }
}