Question

我正在使用计时器循环在我的Java应用程序上实现动画。目前我正在使用与动画相关的静态变量（开始时间，元素的起点和起始位置）。有更简单的方法吗？我可以在启动计时器时将这些变量作为参数发送吗？

...
import javax.swing.Timer;

public class SlidePuzz2 extends Applet implements MouseMotionListener, MouseListener {
...

    static Element animating;
    static PieceLoc blank;
    static int delta;
    static int orig_x;
    static int orig_y;
    static long timeStart;

    Timer aniTimer;

...
    public void init() {
...        
        aniTimer = new Timer(20, new ActionListener() {
            public void actionPerformed(ActionEvent evt) {
                    int dx = (blank.x*piece-orig_x);
                    int dy = (blank.y*piece-orig_y);
                    int t = 200;
                    delta = (int)(System.currentTimeMillis()-timeStart);
                    if (delta>t) delta=t;
                    animating.x = orig_x + dx*delta/t;
                    animating.y = orig_y + dy*delta/t;
                    repaint();
                    if (delta==t) {
                        animating.updateCA();
                        board.checkCompleted();
                        aniTimer.stop();
                    }
               }
        });
...
            setCursor(Cursor.getPredefinedCursor(Cursor.DEFAULT_CURSOR));

            blank = board.getBlankPl();
            animating = e;
            timeStart = System.currentTimeMillis();
            orig_x = animating.x;
            orig_y = animating.y;

            aniTimer.start();
...

Answer 1

感谢@Max的评论，我找到了解决自己问题的方法，在我的主Applet类中创建了一个扩展ActionListener的内部类。

public class AniTimer implements ActionListener {
    Element animating;
    PieceLoc blank;
    int orig_x;
    int orig_y;
    long timeStart;
    int delta;

    public AniTimer(Element e, PieceLoc pl) {
        animating = e;
        blank = pl;
        orig_x = animating.x;
        orig_y = animating.y;
        timeStart = System.currentTimeMillis();
    }

        public void actionPerformed(ActionEvent evt) {
        int dx = (blank.x*piece-orig_x);
        int dy = (blank.y*piece-orig_y);
        int t = 200;
        delta = (int)(System.currentTimeMillis()-timeStart);
        if (delta>t) delta=t;
        animating.x = orig_x + dx*delta/t;
        animating.y = orig_y + dy*delta/t;
        repaint();
        if (delta==t) {
            aniTimer.stop();
            animating.updateCA();
            board.checkCompleted();
        }
    }
}

然后，当我想要开始动画时，我所做的就是创建一个新的Timer，将我的ActionListener类的新实例作为第二个参数，我可以将与此特定动画限制相关的所有重要参数传递给构造函数

aniTimer = new Timer(20, new AniTimer(e, board.getBlankPl()));
aniTimer.start();

谢谢Max，我现在开始喜欢Java了！

如何在Java中使用swing Timer更好地实现动画

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