scrollform.java

在eclipse的环境下

import javax.microedition.lcdui.Command;
import javax.microedition.lcdui.CommandListener;
import javax.microedition.lcdui.Display;
import javax.microedition.lcdui.Displayable;
import javax.microedition.lcdui.Form;
import javax.microedition.lcdui.StringItem;
import javax.microedition.midlet.MIDlet;
import javax.microedition.midlet.MIDletStateChangeException;

public class ScrollForm extends MIDlet  implements CommandListener{
    private Display display;
    
    private Form form;
    
    //定义使用的命令按钮
    private Command cmdExit;	//退出系统
    private Command cmdAdd;	//用于添加条目
    
	public ScrollForm() {
        cmdExit = new Command("退出", Command.EXIT, 0);
        cmdAdd = new Command("添加", Command.ITEM, 0);
        form = new Form("Form中条目的滚动演示");
        //添加一些条目
        for(int i=0;i<20;i++) {
        	form.append("条目" + String.valueOf(i)+"\n");
        }
        form.addCommand(cmdExit);
        form.addCommand(cmdAdd);
        form.setCommandListener((CommandListener) this);
		
	}

	protected void startApp() throws MIDletStateChangeException {
		// TODO Auto-generated method stub
        display = Display.getDisplay(this);
        display.setCurrent(form);
	}

	protected void pauseApp() {
		// TODO Auto-generated method stub
	}

	protected void destroyApp(boolean arg0)
        throws MIDletStateChangeException {
		// TODO Auto-generated method stub
	}
	
    /**
     * 处理命令按钮事件
     */
    public void commandAction(Command cmd, Displayable d) {
        if (cmd == cmdExit) {
        	notifyDestroyed();
        } else if(cmd == cmdAdd) {
        	StringItem item = new StringItem("添加的新条目" + 
        			String.valueOf(form.size()), null);
        	form.append(item);
        	display.setCurrentItem(item);
        }
    }
}