我在 JSplitPane 中有 2 个 DefaultListModel。JSplitPane 的左侧有 RssChannel 标题。When a RssChannel title is selected, the RssItem titles are supposed to show up on the right side of the JSplitPane.
最初选择 RssChannel 标题时,会出现正确的 RssItem 标题。但是当我在 RssChannel 标题之间来回切换时,正确的 RssItem 标题不会触发。
如何修复我的 Listener,以便始终从各自的 RssChannel 触发正确的 RssItem 标题?
感谢您的任何建议
import javax.swing.*;
import javax.swing.event.*;
import java.awt.*;
import java.awt.event.*;
import java.util.List;
import java.util.ArrayList;
import java.io.*;
public class GuiDriver extends JFrame{
JList channelTitleList, itemTitleList;
DefaultListModel cModel, iModel;
List<RssReader> feedList = new ArrayList<RssReader>();
int nextFeed=0;
public GuiDriver(){
}
public void addFeed(RssReader feed){
feedList.add(feed);
}
public JToolBar createToolBar(){
JToolBar bar = new JToolBar();
Action newToolBarButton = new AddAction("New");
Action deleteToolBarButton = new RemoveAction("Delete");
Action clearToolBarButton = new ClearAction("Clear");
bar.add(newToolBarButton);
bar.add(deleteToolBarButton);
bar.add(clearToolBarButton);
bar.setFloatable(false);
return bar;
}
public JSplitPane createJSplitPane(){
JSplitPane hSplitPane = new JSpli tPane(JSplitPane.HORIZONTAL_SPLIT,createChannelJScrollPane(), createItemJScrollPane());
hSplitPane.setDividerLocation(500);
return hSplitPane;
}
public JScrollPane createChannelJScrollPane(){
cModel = new DefaultListModel();
channelTitleList = new JList(cModel);
JScrollPane channelJScrollPane = new JScrollPane(channelTitleList);
channelTitleList.setVisibleRowCount(20);
channelTitleList.getSelectionModel.addListSelectionListener(new ChannelListListener());
return channelJScrollPane;
}
public JScrollPane createItemJScrollPane(){
iModel = new DefaultListModel();
itemTitleList = new JList(iModel);
JScrollPane itemJScrollPane = new JScrollPane(itemTitleList);
return itemJScrollPane;
}
public class AddAction extends AbstractAction{
public AddAction(String name){
super(name);
}
public void actionPerformed(ActionEvent e){
System.out.println(getValue(Action.NAME)+" selected.");
JOptionPane message = new JOptionPane();
String firstInput = message.showInputDialog(null, "Enter URL");
try{
DumpStockPage.readXml(firstInput);
File f = new File("RSSFeed.xml");
addFeed(new RssReader(f));
cModel.addElement(feedList.get(nextFeed).rssChannel.getTitle());
nextFeed++;
iModel.clear();
}
catch (IOException ee){
System.err.println(ee);
}
}
}
public class RemoveAction extends AbstractAction{
public RemoveAction(String name){
super(name);
}
public void actionPerformed(ActionEvent e){
cModel.removeElement(channelTitleList.getSelectedValue());
feedList.remove(e);
iModel.clear();
}
}
public class ClearAction extends AbstractAction{
public ClearAction(String name){
super(name);
}
public void actionPerformed(ActionEvent e){
iModel.clear();
}
}
private class ChannelListListener implements ListSelectionListener {
public void valueChanged (ListSelectionEvent e) {
boolean adjust = e.getValueIsAdjusting();
if (!adjust) {
int i = e.getLastIndex();
for (int j=0; j<feedList.get(i).rssChannel.getItems().size(); j++)
iModel.addElement(feedList.get(i).rssChannel.items.get(j).getTitle());
}
}
}
public static void main(String[] args) {
EventQueue.invokeLater(new Runnable() {
public void run() {
GuiDriver frame = new GuiDriver();
frame.setTitle("RSS Reader");
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.add(frame.createJSplitPane(), BorderLayout.NORTH);
frame.add(frame.createToolBar(), BorderLayout.SOUTH);
frame.setVisible(true);
frame.setSize(800,400);
}
});
}
}