Java actionPerformed 无效

Question

我正在尝试为学校制作一个带有 GUI 的小型二十一点游戏。这是代码：

import java.awt.*; 
import java.awt.event.*;
import javax.swing.*;

public class Gui extends JFrame implements ActionListener {

private JButton bBet;
private JLabel lblPointsPL;
private Blackjack bj;

public Gui() {

    Blackjack bj = new Blackjack();

    bBet = new JButton("Bet!");
    bBet.setBounds(10, 60, 200, 35);
    bBet.setForeground(Color.black);
    bBet.setBackground(Color.yellow);
    this.add(bBet);

    lblPointsPL = new JLabel("PointsPL");
    lblPointsPL.setBounds(300, 50, 200, 35);
    this.add(lblPointsPL);

    lblPointsPL.setText("test1");

}

public void actionPerformed(ActionEvent event) {

    Blackjack bj = new Blackjack();

    if (event.getSource() == bBet) {
        lblPointsPL.setText("test2");
    }

}

}

如果我按下 bBet 按钮，它应该将文本更改为 "test2"，但这不起作用。 "test1" 的第一个更改正在运行。

Answer 1

您忘记为按钮添加动作侦听器。

bBet = new JButton("Bet!");
bBet.setBounds(10, 60, 200, 35);
bBet.setForeground(Color.black);
bBet.setBackground(Color.yellow);
this.add(bBet);
bBet.addActionListener(this); // missing statement.

Java actionPerformed 无效

Java actionPerformed not working

java

swing

awt

jbutton

actionlistener