两个相互关联的组合框[重复]

Question

我有两个组合框...第一个显示酒店的城市，第二个显示基于在第一个组合框中选择的城市的酒店名称。第一个组合框工作正常。第二个节目仅适用于第一个选定的城市。在第一个组合框中更改城市后，它不会对自身进行更改！为了能够通过更改第一个组合框来查看第二个组合框的更改，我必须在此代码中添加什么。

    try
    {

        Class.forName("com.mysql.jdbc.Driver");

        Connection con = DriverManager.getConnection("jdbc:mysql://localhost:3306/JEREN","root","");
        Statement stat = con.createStatement();

        String City_Selected = jComboBox1.getSelectedItem().toString();           
        String select_HN = "select name from tbl_Hotel where city = '"+City_Selected+"';";

        ResultSet rs = stat.executeQuery(select_HN);



        while (rs.next())
        {              
            String hotel_name = rs.getString("name");
           // jLabel3.setText(hotel_name);
            jComboBox2.addItem(hotel_name);

         }//end while

        rs.close();
        stat.close();
        con.close();

         } catch (Exception e) {
              e.printStackTrace();
         } 

Answer 1

像这样？

jComboBox1.addActionListener (new ActionListener () {
    public void actionPerformed(ActionEvent e) {
        jComboBox2.removeAllItems();
        fillComboBoxes();
    }
});

private void fillComboBoxes(){

 try
    {

        Class.forName("com.mysql.jdbc.Driver");

        Connection con = DriverManager.getConnection("jdbc:mysql://localhost:3306/JEREN","root","");
        Statement stat = con.createStatement();

        String City_Selected = jComboBox1.getSelectedItem().toString();           
        String select_HN = "select name from tbl_Hotel where city = '"+City_Selected+"';";

        ResultSet rs = stat.executeQuery(select_HN);



        while (rs.next())
        {              
            String hotel_name = rs.getString("name");
           // jLabel3.setText(hotel_name);
            jComboBox2.addItem(hotel_name);

         }//end while

        rs.close();
        stat.close();
        con.close();

         } catch (Exception e) {
              e.printStackTrace();
         } 

}