我的JavaFX媒体播放器无法持续显示视频。有时候第一次尝试就能正常工作，有时候需要3到4次尝试。按钮和其他事件确实发生了，只是视频没有显示/链接到MediaView。文件是通过fileChooser选择的，我认为与此相关的东西可能是实际问题。我将从我的控制器中删除相关代码：

@FXML
    private void handleOpenFile() {
        // Create a file chooser dialog and set the initial directory
        FileChooser fileChooser = new FileChooser();
        fileChooser.setInitialDirectory(new File(System.getProperty("user.home")));
        // Filter for media files
        FileChooser.ExtensionFilter filter = new FileChooser.ExtensionFilter(
                "Media Files (*.mp4, *.mp3, *.wav, *.jpg, *.png)", "*.mp4", "*.mp3", "*.wav", "*.jpg", "*.png");
        fileChooser.getExtensionFilters().add(filter);
        // Show the file chooser dialog and get the selected file
        Stage stage = (Stage) mediaView.getScene().getWindow();
        openFile(fileChooser.showOpenDialog(stage));
    }
    private void openFile(File file){
        if (file != null) {
            this.file=file;
            // Check if the selected file is a media file or an image
            String filename = file.getName();
            String extension = filename.substring(filename.lastIndexOf(".") + 1).toLowerCase();
            if (extension.equals("jpg") || extension.equals("png")) {
                // Display the selected image in the image view
                disableVideo();
                imageView.setImage(new Image(file.toURI().toString()));
            } else {
                // Create a media player and set it to the media view
                disableImage();
                Media media = new Media(file.toURI().toString());
                mediaPlayer = new MediaPlayer(media);
                mediaView.setMediaPlayer(mediaPlayer);
                // Bind the time slider to the media player's current time
                timeSlider.valueProperty().addListener((observable, oldValue, newValue) -> {
                    if (timeSlider.isValueChanging()) {mediaPlayer.seek(Duration.seconds(newValue.doubleValue()));}
                });
                mediaPlayer.currentTimeProperty().addListener((observable, oldValue, newValue) -> {
                    if (!timeSlider.isValueChanging()) {timeSlider.setValue(newValue.toSeconds());}
                });
                mediaPlayer.setOnReady(() -> timeSlider.setMax(mediaPlayer.getMedia().getDuration().toSeconds()));
            }
        }
    }
private void disableImage(){
        mediaView.setVisible(true);
        imageView.setVisible(false);
        playButton.setVisible(true);playButton.setDisable(false);
        timeSlider.setVisible(true);timeSlider.setDisable(false);
    }
    private void disableVideo(){
        pause();
        mediaView.setVisible(false);
        imageView.setVisible(true);
        playButton.setVisible(false);playButton.setDisable(true);
        timeSlider.setVisible(false);timeSlider.setDisable(true);
    }
    private void pause(){
        if (mediaPlayer != null) {
            mediaPlayer.pause();
            isPlaying = false;
            playButton.setText("Play");
        }
    }
    @FXML
    private void handlePlay() {
        if (mediaPlayer != null && !isPlaying) {
            mediaPlayer.play();
            isPlaying = true;
            playButton.setText("Pause");
            mediaPlayer.setOnEndOfMedia(() -> {
                mediaPlayer.seek(Duration.ZERO);
                pause();
            });
        }else pause();
    }

    @FXML
    private void handleTimeSliderChanged() {
        if (mediaPlayer != null) {
            mediaPlayer.seek(mediaPlayer.getMedia().getDuration()
                    .multiply(timeSlider.getValue() / timeSlider.getMax()));
        }
    }