Question

The method addItem(String) is undefined for the type JComboBox 开发环境eclipse3.6+jdk1.6

程序：
import java.awt.BorderLayout;
import java.awt.event.*;
import java.awt.*;
import javax.swing.*;

public class ComboBoxDemo extends JApplet implements ItemListener{
JPanel panel = new JPanel();
JComboBox os = new JComboBox(),
browser = new JComboBox();
JTextArea ta=new JTextArea(4,20);
JScrollPane jsp=new JScrollPane(ta);
public void init(){
os.addItem("windows"); //
os.addItem("linux");//
os.addItem("android");//
os.addItem("mac ox");//

browser.addItem("IE");//
browser.addItem("HF");//
browser.addItem("SE");//

panel.add(os);
panel.add(browser);
add(panel,BorderLayout.NORTH);
add(jsp,BorderLayout.CENTER);

os.addItemListener(this);//
browser.addItemListener(this);//

}

public void itemStateChanged(ItemEvent e) {
String s1 ="操作系统：",
s2 ="浏览器：";

s1 = s1+os.getSelectedItem()+"\n";//
s2 = s1+browser.getSelectedItem()+"\n";//

}

}

//是报错的地方

Answer 1

JComboBox os = new JComboBox(),
browser = new JComboBox();
改成：
JComboBox os, browser;
os = new JComboBox(),
browser = new JComboBox();
或者：
JComboBox os = new JComboBox();
JComboBox browser = new JComboBox();