傳遞JFrame中組件List的ActionListener

Question

我很困惑，我見過的許多例子只涉及一個按鈕監聽器被傳遞。 我希望能夠將View類的所有組件（JFrame）傳遞給Controller類，它可以輕松訪問這些組件的偵聽器。 我怎么能這么容易做到 這是我到目前為止用JMenuItem做的，但是在JFrame中我有更多的按鈕，不想每次都在構造函數中重復。

 public class EventController implements ActionListener {
    private EventModel model;
    private EventView view;



    public EventController(){
        model = new EventModel(); 

    }


    @Override
   public void actionPerformed(ActionEvent e) {
       if (e.getActionCommand().equals("add")) {
       JOptionPane.showMessageDialog(null, "add button clicked");
   }   else if (e.getActionCommand().equals("edit")) {
       JOptionPane.showMessageDialog(null, "edit button clicked");
   }   else if (e.getActionCommand().equals("delete")) {
       JOptionPane.showMessageDialog(null, "delete button clicked");
  }


    }   

//類視圖

  public class EventView extends javax.swing.JFrame {
Connection conn = JavaConnect.ConnectDB();
PreparedStatement pst = null; 
ResultSet rs = null; 


    public EventView() {
        initComponents();
        updateEventTable();
        addEvent.addActionListener(new EventController());
        addEvent.setActionCommand("add");
        editEvent.addActionListener(new EventController());
        editEvent.setActionCommand("edit");
        deleteEvent.addActionListener(new EventController());
        deleteEvent.setActionCommand("delete");
    }
    public void updateEventTable() {
        try {
            String sql = "SELECT date as 'Date',eventName as 'Name', time as 'Start Time' FROM Event";
             pst = conn.prepareStatement(sql); 
             rs = pst.executeQuery();
             tableEvent.setModel(DbUtils.resultSetToTableModel(rs));
             tableEvent.getColumnModel().getColumn(0).setPreferredWidth(80);
             tableEvent.getColumnModel().getColumn(1).setPreferredWidth(170);
             tableEvent.getColumnModel().getColumn(2).setPreferredWidth(110);  
    }
        catch (Exception e ) {
                     JOptionPane.showMessageDialog(null, e);
        } finally {
            try {
                rs.close(); pst.close();conn.close();;
            } catch(SQLException e){}
        }


    }

Answer 1

只創建一次偵聽器實例並重用它。 像這樣

    EventController lst=new EventController();
    addEvent.addActionListener(lst);
    addEvent.setActionCommand("add");
    editEvent.addActionListener(lst);
    editEvent.setActionCommand("edit");
    deleteEvent.addActionListener(lst);
    deleteEvent.setActionCommand("delete");

Answer 2

添加如下方法：

private void setListener(AbstractButton button, ActionListener listener, String command) {
  button.addActionListener(listener);
  button.setActionCommand(command);
}

構建一個EventController實例。

EventController controller = new EventController();

然后，為每個按鈕調用它：

setListener(addEvent, controller, "add");
...