imageitemdemo.java

人民邮电出版社的《J2ME手机开发入门》全部源代码

/*
 * ImageItemDemo.java
 *
 * Created on 2005年4月4日, 下午2:43
 */

import javax.microedition.midlet.*;
import javax.microedition.lcdui.*;
import javax.microedition.io.*;
import java.io.*;
/**
 *
 * @author  Liu Bin
 * @version
 */
public class ImageItemDemo extends MIDlet implements ItemCommandListener {
    private Display display;
    private Form form;
    
    private Command cmdSelect;
    //退出命令按钮
    private Command cmdExit;
    
    //第一个ImageItem对象
    private ImageItem imgItem1;
    //第二个ImageItem对象
    private ImageItem imgItem2;
    
    public ImageItemDemo() {
        try {
            nbInit();
        } catch(Exception e) {
            e.printStackTrace();
        }
    }
    
    private void nbInit() throws Exception {
        form = new Form("ImageItem演示");
        
        Image img1 = Image.createImage("/robin.jpg");
        imgItem1 = new ImageItem("请单击下面的图像", img1,
                Item.LAYOUT_CENTER + Item.LAYOUT_EXPAND +
                Item.LAYOUT_NEWLINE_AFTER,
                null, Item.BUTTON);
        cmdSelect = new Command("选择", Command.ITEM, 1);
        imgItem1.setDefaultCommand(cmdSelect);
        imgItem1.setItemCommandListener(this);
        form.append(imgItem1);
        
        Image img2 = Image.createImage("/exit.PNG");
        imgItem2 = new ImageItem("单击退出", img2,
                Item.LAYOUT_CENTER + Item.LAYOUT_EXPAND +
                Item.LAYOUT_NEWLINE_AFTER,
                null, Item.BUTTON);
        cmdExit = new Command("退出", Command.ITEM, 1);
        imgItem2.setDefaultCommand(cmdExit);
        imgItem2.setItemCommandListener(this);
        form.append(imgItem2);
    }
    
    public void startApp() {
        display = Display.getDisplay(this);
        display.setCurrent(form);
    }
    
    
    public void pauseApp() {
    }
    
    
    public void destroyApp(boolean unconditional) {
        notifyDestroyed();
    }
    
    /**
     * 处理命令按钮事件
     */
    public void commandAction(Command cmd, Item i) {
        if (cmd == cmdSelect) {
            form.append("请爱护动物，保护环境\n");
        }
        
        if (cmd == cmdExit) {
            destroyApp(false);
        }
    }
}