这是一个简单的程序,它应该从颜色列表中更改窗格的背景颜色。但是,
import java.awt.Color;
import java.awt.FlowLayout;
import javax.swing.JFrame;
import javax.swing.JTextField;
import java.awt.Font;
import javax.swing.ButtonGroup;
import javax.swing.JFrame;
import javax.swing.JButton;
import javax.swing.Icon;
import javax.swing.ImageIcon;
import javax.swing.JList;
import javax.swing.JOptionPane;
import javax.swing.JCheckBox;
import javax.swing.JScrollPane;
import javax.swing.ListSelectionModel;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.awt.event.ItemEvent;
import java.awt.event.ItemListener;
import javax.swing.JRadioButton;
import javax.swing.event.ListSelectionListener;
public class JL1st extends JFrame{
private JList list;
private static String[] colornames = {"black","blue","red","white"};
private static Color[] colors = {Color.BLACK, Color.BLUE, Color.RED, Color.WHITE};
public JL1st(){
super("title");
setLayout(new FlowLayout());
list = new JList(colornames);
list.setVisibleRowCount(4);
list.setSelectionMode(ListSelectionModel.SINGLE_SELECTION);
add(new JScrollPane(list));
list.ListSelectionListener(
new ListSelectionListener(){
public void valueChanged(ListSelectionEvent event){
getContentPane().setBackground(colors[list.getSeletedIndex]);
}
}
);
}
}
我在" ListSelectionListener"上一直收到错误方法ListSelectionListener(new ListSelectionListener(){})未定义类型JList 可能是我缺少导入还是只是搞砸了语法? 感谢
答案 0 :(得分:0)
问题解决了, 未导入ListSelectionListener。