Java - 关闭JFrame窗口时的消息

3 回答

• 0

  基本上，你几乎是正确的 . 有些事情没有正确拼凑而成 .

  首先删除你的 WindowClosing 方法（它是 window ，而不是 Window ）然后用下面的代码替换你的 addWindowListener(new WindowAdapter());

  addWindowListener(new WindowAdapter() {
    public void windowClosing(WindowEvent e) {
      int confirmed = JOptionPane.showConfirmDialog(null, 
          "Are you sure you want to exit the program?", "Exit Program Message Box",
          JOptionPane.YES_NO_OPTION);
  
      if (confirmed == JOptionPane.YES_OPTION) {
        dispose();
      }
    }
  });
  

  回复于 2024-04-19T13:19:16+08:00
• 14

  我在两分钟内得到了这个......

  首先在Exit_on_close中设置j帧默认关闭事件 . 其次创建一个名为“Window Closing Event Handler”的类，然后在i nit阶段调用它 .

  private void WindowClosingEventHandler(){ addWindowListener(new WindowAdapter() { @Override public void windowClosing(WindowEvent e) { int confirmed = JOptionPane.showConfirmDialog(null, "Are you sure you want to exit this application?", "Exit Program Message Box",JOptionPane.YES_NO_OPTION);
  
      if (confirmed == JOptionPane.YES_OPTION) {
          try{
              String login=txtuserid.getText();
              Connection conn = (Connection) DriverManager.getConnection("jdbc:mysql://localhost:3306/repair", "root", "");
              Statement st = conn.createStatement();
              String update = "UPDATE user set User_Status=0 where UserID='"+ login +"'";
              st.executeUpdate(update);  
              dispose();
              Login2 dialog = new Login2(new javax.swing.JFrame(), true);
              dialog.setVisible(true);
          }catch(SQLException | HeadlessException q){
              JOptionPane.showMessageDialog(null, q);
          }
          System.exit(0);
      }
      else{
          setDefaultCloseOperation(javax.swing.WindowConstants.DO_NOTHING_ON_CLOSE);
      }
  }
  });
  }
  

  回复于 2024-04-19T13:19:16+08:00
• 2

  好的再试一次 .

  您无法创建新的WindowAdapter，因为WindowAdapter是抽象的 . 抽象类无法实例化 . 您需要创建WindowAdapter的子类并将其抽象方法实现为public .

  http://docs.oracle.com/javase/7/docs/api/java/awt/event/WindowAdapter.html

  回复于 2024-04-19T13:19:16+08:00