雪佛兰小跑车多少钱:这段程序的setlayout哪里出错了？？？希望指导

package phonebook;

import java.io.*;
import javax.microedition.io.*;
import javax.microedition.lcdui.*;
import javax.microedition.midlet.*;
import javax.microedition.rms.RecordEnumeration;
import javax.microedition.rms.RecordFilter;
import javax.microedition.rms.RecordStore;

public class FindRecord extends Form implements CommandListener {

private Displayable dis;

private MIDlet mid;

private RecordStore rs = null;

private RecordEnumeration re = null;

private static final Command findCommand = new Command("查找", Command.OK, 1);

private static final Command backCommand = new Command("返回", Command.BACK,
2);

private TextField tf;

public FindRecord(Displayable dis,MIDlet mid,RecordStore rs) {
super("查询记录");

tf = new TextField("输入名字",null, 120,TextField.ANY);
//设置控件的布局
tf.setLayout(Item.LAYOUT_NEWLINE_AFTER);

this.append(tf);

this.dis = dis;
this.mid = mid;
this.rs = rs;

this.addCommand(backCommand);
this.addCommand(findCommand);
this.setCommandListener(this);
}

public void commandAction(Command c, Displayable d) {
if (c == backCommand) {
Display.getDisplay(mid).setCurrent(dis);
}
if (c == findCommand) {

RecordFilter rf = new FindFilter(tf.getString());
RecordEnumeration re = null;
try {
re = rs.enumerateRecords(rf, null, false);
} catch (Exception e) {
}
//查找成功
if (re.numRecords() > 0) {
BookAccount account = null;
int recordID;
try {
byte[] rec;
recordID = re.nextRecordId();
rec = rs.getRecord(recordID);
account = BookAccount.deserialize(rec);
StringItem name = new StringItem("姓名：",account.getUserName());
StringItem mobilePhone = new StringItem("移动电话：",account.getMobilePhone());
StringItem phone = new StringItem("家庭电话：",account.getPhone());
StringItem email = new StringItem("电子邮件：",account.getEmail());

name.setLayout(Item.LAYOUT_NEWLINE_AFTER);
mobilePhone.setLayout(Item.LAYOUT_NEWLINE_AFTER);
phone.setLayout(Item.LAYOUT_NEWLINE_AFTER);
email.setLayout(Item.LAYOUT_NEWLINE_AFTER);

this.append(name);
this.append(mobilePhone);
this.append(phone);
this.append(email);
account = null;
re.destroy();

} catch (Exception e) {
account = null;
System.out.println("deserialize error");
}
}
}
}

}