如何在Swing中创建延迟

Question

我做了一个二十一点游戏，我想让AI播放器在两张牌之间暂停一下。我尝试仅使用Thread.sleep（x）进行尝试，但这会使冻结，直到AI播放器拿走了他所有的卡。我知道Swing不是线程安全的，所以我看了Timers，但是我不明白如何使用它。这是我当前的代码：

while (JB.total < 21) {

          try {
            Thread.sleep(1000);
          } catch (InterruptedException ex) {
            System.out.println("Oh noes!");
          }

          switch (getJBTable(JB.total, JB.aces > 0)) {
            case 0:
              JB.hit();
              break;
            case 1:
              break done;
            case 2:
              JB.hit();
              JB.bet *= 2;
              break done;
          }
        }

BTW，hit（）; 方法更新GUI。

Answer 1

好吧，下面的代码显示了一个带有JTextArea和JButton的JFrame。单击按钮后，计时器将事件重复发送（事件之间有第二个延迟）到与按钮相关的actionListener，后者在当前时间后追加一行。

import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.util.Calendar;

import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JTextArea;
import javax.swing.Timer;


public class TimerTest extends JFrame implements ActionListener{

    private static final long serialVersionUID = 7416567620110237028L;
    JTextArea area;
    Timer timer;
    int count; // Counts the number of sendings done by the timer
    boolean running; // Indicates if the timer is started (true) or stopped (false)

    public TimerTest() {
        super("Test");
        setBounds(30,30,500,500);
        setDefaultCloseOperation(EXIT_ON_CLOSE);
        setLayout(null);

        area = new JTextArea();
        area.setBounds(0, 0, 500, 400);
        add(area);

        JButton button = new JButton("Click Me!");
        button.addActionListener(this);
        button.setBounds(200, 400, 100, 40);
        add(button);

        // Initialization of the timer. 1 second delay and this class as ActionListener
        timer = new Timer(1000, this);
        timer.setRepeats(true); // Send events until someone stops it
        count = 0; // in the beginning, 0 events sended by timer
        running = false;
        System.out.println(timer.isRepeats());
        setVisible(true); // Shows the frame
    }

    public void actionPerformed(ActionEvent e) {
        if (! running) {
            timer.start();
            running = true;
        }
        // Writing the current time and increasing the cont times
        area.append(Calendar.getInstance().getTime().toString()+"\n");
        count++;
        if (count == 10) {
            timer.stop();
            count = 0;
            running = false;
        }
    }

    public static void main(String[] args) {
        // Executing the frame with its Timer
        new TimerTest();
    }
}

好的，此代码是如何使用javax.swig.Timer对象的示例。关于问题的具体情况。停止计时器的if语句必须更改，并且显然必须更改actionPerformed的操作。以下片段是解决方案actionPerformed的框架：

public void actionPerformed(ActionEvent e) {
    if (e.getComponent() == myDealerComponent()) {
    // I do this if statement because the actionPerformed can treat more components
        if (! running) {
            timer.start();
            runnig = true;
        }
        // Hit a card if it must be hitted
        switch (getJBTable(JB.total, JB.aces > 0)) {
          case 0:
              JB.hit();
              break;
          case 1:
              break done;
          case 2:
              JB.hit();
              JB.bet *= 2;
              break done;
        }
        if (JB.total >= 21) { // In this case we don't need count the number of times, only check the JB.total 21 reached
            timer.stop()
            running = false;
        }

    }
}

恕我直言，这可以解决问题，现在@ user920769必须考虑将actionListener和启动/停止条件放在哪里…

@kleopatra：感谢您向我展示这个计时器类的存在，对此我一无所知，这真是太神奇了，它可以将很多任务分配到一个swing应用程序中：）