java - AddActionListener 在我的 JButton 上不起作用

Question

JButton我正在尝试在我认为的名为 btnNew上放置一个动作侦听器：

看法：

public class MyWindow6 extends JFrame
{
    private JButton btnNew;

    private static final long serialVersionUID = 6579944958990616196L;

    public static void main(String[] args) throws UnsupportedLookAndFeelException
    {
        UIManager.setLookAndFeel(new NimbusLookAndFeel());
        MyWindow6 myWindow = new MyWindow6();
        myWindow.setVisible( true );

        public MyWindow6()
        {
            super( "JMenu sample" );

            btnNew = new JButton( new ImageIcon( "icons/save.png"));
            this.setSize(1200,800);
            this.setLocationRelativeTo( null );
            this.setDefaultCloseOperation( DISPOSE_ON_CLOSE );

            JPanel contentPane = (JPanel) this.getContentPane();

            JScrollPane leftScrollPane = new JScrollPane( new JTree());
            leftScrollPane.setPreferredSize( new Dimension(200, 0));
            contentPane.add( leftScrollPane, BorderLayout.WEST);

            JTable t = new JTable(DaoClef.createModel());
            JScrollPane scrollPane = new JScrollPane(t);
            t.setFillsViewportHeight(true);

            add(scrollPane, BorderLayout.CENTER);

            // toolbar
            JToolBar jtb = new JToolBar();
            btnNew.setToolTipText("Ajouter clef (CTRL + N");
            jtb.add(btnNew);
            contentPane.add(jtb, BorderLayout.NORTH);
        }
        
        public JButton getBtnNew() {
            return btnNew;
        }
        public void setBtnNew(JButton btnNew) {
            this.btnNew = btnNew;
        }
    }
} 

控制器 ：

public class Controller2 {

    private DaoClef dao;
    private MyWindow6 view;

    public Controller2(DaoClef d, MyWindow6 v) {
        dao = d;
        view = v;
    }

    public void initController() {

        view.getBtnNew().addActionListener(e -> delete());
    }

    private void delete() {
        System.out.println("hello");
    }
}

我没有错误，只是println根本不工作。

你知道为什么这不起作用吗？控制器和视图似乎没有连接。

如果你有任何关于在 Swing 中使用 MVC 的建议，我会有点困惑，因为我不知道把我的听众放在哪里。

标签： javaswingmodel-view-controlleractionlistener

Answer 1

像下面这样发布 mcve，使问题和解决方案易于理解和重现：

import java.awt.BorderLayout;
import javax.swing.JButton;
import javax.swing.JFrame;

public class MyWindow6 extends JFrame
{
    private final JButton btnNew;
    public static void main(String[] args){
        new Controller2(new MyWindow6());
    }
    public MyWindow6()      {

        btnNew = new JButton( "Delete");
        this.setSize(120,80);
        this.setDefaultCloseOperation( DISPOSE_ON_CLOSE );
        add(btnNew, BorderLayout.PAGE_START);
        setVisible(true);
    }

    public JButton getBtnNew() {
        return btnNew;
    }
}

class Controller2 {

    private final MyWindow6 view;

    public Controller2(MyWindow6 v) {

        view = v;
        view.getBtnNew().addActionListener(e -> delete());
    }

    private void delete() {
        System.out.println("delete btn clicked");
    }
}