我正在尝试制作一个直播电视应用程序，但当我播放.mp4链接时，mediacontroller播放/暂停按钮工作，但当我尝试播放.m3u8链接时，播放/暂停按钮不工作。我是 java 新手。。。这是密码。

private void playVideo() {
    try {
        getWindow().setFormat(PixelFormat.TRANSLUCENT);
        MediaController mediaController = new MediaController(this);
        mediaController.setAnchorView(videoView);
        videoView.setMediaController(mediaController);
        String videoUrl = "http://My_HLS_Link.m3u8";
        Uri videoUri = Uri.parse(videoUrl);
        videoView.setVideoURI(videoUri);
        videoView.requestFocus();
        videoView.setOnPreparedListener(new MediaPlayer.OnPreparedListener() {
            @Override
            public void onPrepared(MediaPlayer mediaPlayer) {
                mediaPlayer.start();
                mediaController.show(0);
                pd.dismiss();
                videoView.start();

            }
        });
    }
    catch (Exception e) {
        pd.dismiss();
        Toast.makeText(this, "Time Out! Please Try Again"+e.getMessage(), Toast.LENGTH_SHORT).show();
    }
}

`