如何在java中的组合框之间使用过滤器? [英] How can I use filter between comboboxes in java?
问题描述
我在我的数据库中有两个表作为学期表和课程表。在学期表中有semesterId,courseId,courseName和Sdepartment(部门名称)。课表具有courseId和courseName。
我有两个组合框我的jframe.First一个是选择一个部门。第二个是选择课程。我想选择课程选定的部门。
当我选择一个部门时,我如何在组合框中调用课程名称?
我的代码;
I have two tables in my database as semester table and course table.There are semesterId,courseId,courseName and Sdepartment(department name)in semester table.Course table has courseId and courseName. I have two comboboxes my jframe.First one is for select a department.Second one is select course.I want to select course as to selected department. How can i call course name in combobox when i select a department? Here my code;
public void coursename(){
Session session = HibernateUtil.getSessionFactory().getCurrentSession();
session.beginTransaction();
//Query query= session.createQuery("select a.courseName,e.semesterId from Semester e inner join e.course as a");
Query query= session.createQuery("FROM Senior.entity.Semester S ");
//for (Iterator it = query.iterate(); it.hasNext();) {
//Object row[] = (Object[]) it.next();
//combocourse.addItem(new CourseItem((String)row[0], (int)row[1]));
//}
List <Semester>re= query.list();
if (re.size() > 0){
Iterator iterate= re.iterator();
final Semester resultAccount= (Semester)iterate.next();
combocourse.removeAllItems();
for(Semester inv:re){
combocourse.addItem(new CourseItem(inv.getSemesterId(),inv.getSCourse()));
}
}
session.close();
}
public void depart(){
Session session = HibernateUtil.getSessionFactory().getCurrentSession();
session.beginTransaction();
Query query= session.createQuery("FROM Senior.entity.Semester f ");
List <Semester>results= query.list();
if (results.size() > 0){
Iterator iterate= results.iterator();
final Semester resultAccount= (Semester)iterate.next();
combodepart.removeAllItems();
for(Semester inv:results){
combodepart.addItem(new DepartItem(inv.getSemesterId(),inv.getSDepartment()));
// combodepart.addActionListener(combocourse);
/*
@Override
public void actionPerformed(ActionEvent e) {
JComboBox combocourse;
combocourse = (JComboBox) e.getSource();
// Object selected = combocourse.getSelectedItem();
Session session = HibernateUtil.getSessionFactory().getCurrentSession();
session.beginTransaction();
Query query= session.createQuery("FROM Senior.entity.Semester f ");
List <Semester>results= query.list();
if (results.size() > 0){
Iterator iterate= results.iterator();
final Semester resultAccount= (Semester)iterate.next();
combodepart.removeAllItems();
for(Semester inv:results){
combodepart.addItem(new DepartItem(inv.getSemesterId(),inv.getSDepartment()));
}
});
*/
}
}
session.close();
}
推荐答案
类似于:
import java.awt.*;
import java.awt.event.*;
import java.util.*;
import javax.swing.*;
public class ComboBoxTwo extends JPanel implements ActionListener
{
private JComboBox<String> mainComboBox;
private JComboBox<String> subComboBox;
private Hashtable<String, String[]> subItems = new Hashtable<String, String[]>();
public ComboBoxTwo()
{
String[] items = { "Select Item", "Color", "Shape", "Fruit" };
mainComboBox = new JComboBox<String>( items );
mainComboBox.addActionListener( this );
// prevent action events from being fired when the up/down arrow keys are used
mainComboBox.putClientProperty("JComboBox.isTableCellEditor", Boolean.TRUE);
add( mainComboBox );
// Create sub combo box with multiple models
subComboBox = new JComboBox<String>();
subComboBox.setPrototypeDisplayValue("XXXXXXXXXX"); // JDK1.4
add( subComboBox );
String[] subItems1 = { "Select Color", "Red", "Blue", "Green" };
subItems.put(items[1], subItems1);
String[] subItems2 = { "Select Shape", "Circle", "Square", "Triangle" };
subItems.put(items[2], subItems2);
String[] subItems3 = { "Select Fruit", "Apple", "Orange", "Banana" };
subItems.put(items[3], subItems3);
}
public void actionPerformed(ActionEvent e)
{
String item = (String)mainComboBox.getSelectedItem();
Object o = subItems.get( item );
if (o == null)
{
subComboBox.setModel( new DefaultComboBoxModel() );
}
else
{
subComboBox.setModel( new DefaultComboBoxModel( (String[])o ) );
}
}
private static void createAndShowUI()
{
JFrame frame = new JFrame("SSCCE");
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.add( new ComboBoxTwo() );
frame.setLocationByPlatform( true );
frame.pack();
frame.setVisible( true );
}
public static void main(String[] args)
{
EventQueue.invokeLater(new Runnable()
{
public void run()
{
createAndShowUI();
}
});
}
}
如何转换示例到数据库?
How to convert this example to database?
在ActionListener中,查询数据库以获取所选部门的课程,然后创建模型。
In the ActionListener you query the database to get the courses for the selected department and then you create the model.
这篇关于如何在java中的组合框之间使用过滤器?的文章就介绍到这了,希望我们推荐的答案对大家有所帮助,也希望大家多多支持IT屋!