Question

java jcheckbox无法选中

选中运动后，会同时跳出选中和取消的窗口，关闭之后，勾子还是没打上。import java.awt.*;import java.awt.event.*;import javax.swing.*;public class Ex3344 extends JFrame{ JComboBox s; JCheckBox t1,t2,t3; Ex3344(String stitle){ super(stitle); JPanel panel1=new JPanel(); panel1.setLayout(new FlowLayout()); panel1.add(new JLabel(" 出生地：")); String stu[]={"杭州","北京","东莞","梅州"}; s=new JComboBox(stu); panel1.add(s); JPanel panel2=new JPanel(); panel2.setLayout(new GridLayout(3,1,5,5));//卡片布局，3行1列 t1=new JCheckBox("运动");t2=new JCheckBox("旅游");t3=new JCheckBox("上网"); panel2.add(t1); t1.setSelected(true); panel2.add(t2); panel2.add(t3); JPanel panel4=new JPanel(); panel4.setLayout(new BorderLayout()); panel4.add(new JLabel(" 业余爱好："),"West"); panel4.add(panel2,"Center"); JPanel panel3=new JPanel(); panel3.setLayout(new BorderLayout()); panel3.add(panel1,"North"); panel3.add(panel4,"South"); setContentPane(panel3); s.addItemListener(new ItemListener(){ public void itemStateChanged(ItemEvent e){ if(s.getSelectedItem()==e.getItem()){ JOptionPane.showMessageDialog(null, "你选择的选项是"+e.getItem(), "提示", JOptionPane.INFORMATION_MESSAGE); } } }); t1.addItemListener(new ItemListener(){ public void itemStateChanged(ItemEvent e){ if(e.getStateChange() == e.SELECTED){ JOptionPane.showMessageDialog(null, "你选择了爱好："+t1.getText(), "提示", JOptionPane.INFORMATION_MESSAGE); } else JOptionPane.showMessageDialog(null, "你取消了爱好："+t1.getText(), "提示", JOptionPane.INFORMATION_MESSAGE); } }); } public static void main(String[] args) { // TODO Auto-generated method stub Ex3344 frm=new Ex3344("测试ItemListener!"); frm.setVisible(true); }}

Answer 1

不要在该事件中使用 JOptionPane.showMessageDialog
换成System.out.来输出
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追问

可以解释下为什么吗？

追答

事件、消息问题

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