java - 抽象动作实现

Question

由于错误，它不会让我运行程序：类型BingoHelper必须实现继承的抽象方法ActionListener.actionPerformed(ActionEvent)

public class BingoHelper extends JFrame implements WindowListener, ActionListener{
JButton b = new JButton(new AbstractAction("Enter"){

                public void actionPerformed (ActionEvent e){

Answer 1

该actionPerformed方法不是 的成员BingoHelper。您应该创建该类的方法BingoHelper并实现它。

public class BingoHelper extends JFrame implements WindowListener, ActionListener{
  public void actionPerformed (ActionEvent e){}

Answer 2

BingoHelper 类没有实现actionPerformed. 您扩展的匿名类AbstractAction确实实现了它，但它不是一回事。

Answer 3

从 中删除匿名侦听器JButton并实现actionPerformed内部BingoHelper并向其注册按钮操作侦听器

public class BingoHelper extends JFrame implements WindowListener, ActionListener {
    JButton b = new JButton("Enter");

    //...

    b.addActionListener(this);

    //...

    public void actionPerformed(ActionEvent evt) {...}

或从中删除ActionListener接口并BingoHelper实现actionPerformedAbstractAction

 public class BingoHelper extends JFrame implements WindowListener {
    JButton b = new JButton(new AbstractAction("Enter"){
        public void actionPerformed (ActionEvent e){...}
    };