listdemo.java

J2ME常用控件使用的例子 Eclipse写的 练手用的

package list;

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

public class ListDemo extends MIDlet implements CommandListener {

    Display display;
    private List mailList;
    private Command cmdRead = new Command("读邮件",Command.SCREEN,1);
    private Command cmdReply = new Command("回复",Command.SCREEN,1);
    private Command cmdDelete = new Command("删除邮件",Command.SCREEN,1);
    private Command cmdExit = new Command("退出",Command.SCREEN,1);
    private Image mailIcon, mailRead;
    private Alert alert;
    
    public ListDemo() {
        System.out.println("调用构造函数");
        try{
        	mailIcon = Image.createImage("/res/MailIcon.png");
        	mailRead = Image.createImage("/res/MailRead.png");
        }catch(java.io.IOException e){
        	System.out.println("载入图标时出现错误！");
        	System.out.println("错误如下：");
        	System.out.println(e);
        }
        display = Display.getDisplay(this);
        alert = new Alert("读取邮件", "", mailRead, AlertType.INFO);
        //alert = new Alert("读取邮件", "", null, AlertType.INFO);
        alert.setTimeout(Alert.FOREVER);
        mailList = new List("邮件列表", List.IMPLICIT);
        mailList.append("邮件1", mailIcon);
        mailList.append("邮件2", mailIcon);
        mailList.append("邮件3", mailIcon);
        mailList.append("邮件4", mailIcon);
        /*mailList.append("邮件1", null);
        mailList.append("邮件2", null);
        mailList.append("邮件3", null);
        mailList.append("邮件4", null);*/
        mailList.addCommand(cmdRead);
        mailList.addCommand(cmdReply);
        mailList.addCommand(cmdDelete);
        mailList.addCommand(cmdExit);
        mailList.setCommandListener(this);
    }

    public void startApp() {
        System.out.println("程序运行");
        display.setCurrent(mailList);
    }

    public void pauseApp() {
        System.out.println("程序暂停");
    }

    public void destroyApp(boolean unconditional) {
        System.out.println("程序退出:" + unconditional);
    }

    public void commandAction(Command c, Displayable d){
    	if(c == cmdRead || c == List.SELECT_COMMAND){
    		alert.setString("邮件:\n" + mailList.getString(mailList.getSelectedIndex()));
    		display.setCurrent(alert,display.getCurrent());
    	}else if(c == cmdDelete){
    		mailList.delete(mailList.getSelectedIndex());
    	}else if(c == cmdExit){
    		this.destroyApp(false);
    		notifyDestroyed();
    	}
    }

}