大家看看啥问题？

照着教程上做了个程序可是运行时屏幕上啥也没有而且模拟器会自动退出！


import javax.microedition.lcdui.Display;
import javax.microedition.lcdui.Form;
import javax.microedition.midlet.MIDlet;
import javax.microedition.midlet.MIDletStateChangeException;
public class 测试 extends MIDlet {
private Form frm=new Form ("第一个程序");
private Display dis;


protected void startApp() throws MIDletStateChangeException
{
dis=Display.getDisplay(this);
dis.setCurrent(frm);

}

protected void pauseApp()
{

}


protected void destroyApp(boolean arg0) throws MIDletStateChangeException {
}
}