JavaFX：在与线程​​循环时冻结MediaPlayer

Question

我正在制作一个屏幕保护程序，该屏幕保护程序使用Java FX循环显示随机视频剪辑。

我的应用程序显示一个时钟，该时钟显示当前时间，向后显示一个影片剪辑。

通常它可以正常工作。但是当我打开它几分钟后，MediaPlayer冻结了。时钟一直在响，但是只有MediaPlayer没有响。

我做了两个主题。一个负责更新时钟，另一个负责更改MediaPlayer。我怀疑更改MediaPlayer的线程处理是否有问题。但是我不知道这是什么。

这是我的代码。

public void start() {
    showIntro();
    mediaV.setMediaPlayer(mediaPlayer);
    if (thread == null) {
        thread = new Thread(this);
        thread.start();
    }
    if (changer_thread == null) {
        changer_thread = new Thread(new Changer());
        changer_thread.start();
    }
}

@Override
public void run() {
    while (true) {
        showCurrentTime();
        try {
            Thread.sleep(1000);
        } catch (InterruptedException e) {
            e.printStackTrace();
        }
    }
}

public class Changer implements Runnable {
    private int interval;

    public Changer(int interval) {
        this.interval = interval;
    }

    public Changer() {
        this.interval = 10000;
    }

    @Override
    public void run() {
        try {
            while (true) {
                Thread.sleep(interval);
                showClip();
                Thread.sleep(interval);
                showIntro();
            }
        } catch (InterruptedException e) {
            e.printStackTrace();
        }
    }
}

public void showIntro() {

    int interval = 5850;

    /* I skipped the code handling about clipInd and groupInd  */

    main.setBg("white");
    timeLabel.setStyle("-fx-opacity: 1.0");
    Media media = new Media(
            this.getClass().getResource("view/Intro_" + IntroString[groupInd] + ".mp4").toExternalForm());

    if (mediaPlayer != null)
        mediaPlayer.dispose();

    mediaPlayer = new MediaPlayer(media);
    mediaPlayer.setAutoPlay(true);

    bg_thread = new Thread(new BgHandler(interval));
    bg_thread.start(); //bg_thread changes main pane's bg color

    mediaV.setMediaPlayer(mediaPlayer); //type of mediaV is MediaView
}

public void showClip() {

    main.setBg("white");
    Media media = new Media(
            this.getClass().getResource("view/Clip_" + IntroString[groupInd] + ".mp4").toExternalForm());

    if (mediaPlayer != null)
        mediaPlayer.dispose();

    mediaPlayer = new MediaPlayer(media);
    double millis = 10000*clipInd;
    mediaPlayer.setStartTime(Duration.millis(millis + 200));
    mediaPlayer.setStopTime(Duration.millis(millis + 10000));

    mediaPlayer.setAutoPlay(true);

    mediaV.setMediaPlayer(mediaPlayer);

}