java - 按下 "enter"键后添加到 JList

Question

我只是想做的是在按回车键之前不要将项目添加到 JList，因为我创建了一个类似 Google 的搜索框。我认为这是组合框没有“读取”“输入”键。

public void count(){

    try{

         String sql2 = "select count(*) from workers_info";

         stmt = conn.prepareStatement(sql2);

         rs=stmt.executeQuery();
         while(rs.next()){
         String x = rs.getString("count(*)");

         z = Integer.parseInt(x);

         }

         auto = new String[z];

     }


      catch(SQLException | NumberFormatException e){

      }

}


public void cB(){

    try{

            String sql = "Select concat(first_name, ' ',last_name) as full_name from workers_info";

            stmt = conn.prepareStatement(sql);
            rs=stmt.executeQuery();

            while(rs.next()){

              String name = rs.getString("full_name");

                auto[i] = name;  

                i++;
             }

             AutoCompleteSupport a = AutoCompleteSupport.install(comboSearch, GlazedLists.eventListOf(auto));
             a.setStrict(false);
             comboSearch.isEditable();


      }

        catch(SQLException e){

        }

    }

    //this actually is my main concern..why it cant detect when i hit "enter" key? 

private void comboSearchKeyPressed(java.awt.event.KeyEvent evt) {                                  
    String s1 = (String)comboSearch.getSelectedItem();   
    if(evt.getKeyCode()==KeyEvent.VK_ENTER){

        model.addElement(s1);

        workerList.setModel(model);

        comboSearch.setSelectedItem(null);
       }
}

Answer 1

为此，我建议您使用 Key bindings而不是 KeyListener。尝试下一个简单的例子:

import java.awt.BorderLayout;
import java.awt.event.ActionEvent;

import javax.swing.AbstractAction;
import javax.swing.DefaultListModel;
import javax.swing.JComboBox;
import javax.swing.JComponent;
import javax.swing.JFrame;
import javax.swing.JList;
import javax.swing.JScrollPane;
import javax.swing.KeyStroke;

public class Example extends JFrame{

    private JComboBox<String> comboBox;
    private JList<String> list;
    private DefaultListModel<String> model;

    Example(){
            comboBox = new JComboBox<>(new String[]{"111","222","333"});
            list = new JList<>(model = new DefaultListModel<>());
            add(comboBox,BorderLayout.SOUTH);
            add(new JScrollPane(list));

            addKeyBindings((JComponent) getContentPane());
            addKeyBindings(comboBox);

            setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
            pack();
            setVisible(true);
    }

    private void addKeyBindings(JComponent c) {
        c.getInputMap(JComboBox.WHEN_ANCESTOR_OF_FOCUSED_COMPONENT).put(KeyStroke.getKeyStroke("ENTER"), "doSomething");
        c.getActionMap().put("doSomething", new AbstractAction() {

            @Override
            public void actionPerformed(ActionEvent e) {
                Object selectedItem = comboBox.getSelectedItem();
                if(selectedItem != null){
                    model.addElement((String)selectedItem);
                }
            }
        });
    }

    public static void main(String[] args) {
         new Example();
    }

}