Java 如何将Pane的图像快照保存为BMP

我已经成功地在同一个面板上绘制了两个图表(条形图和折线图).

我正在try 实现一个保存按钮，当单击该按钮时，会将结果图像(带有轴)写入到我保存的 Select 的BMP图像中.

代码运行，我收到一个肯定的警告，并创建了一个图像文件.但是，生成的图像文件为空(0字节).

@FXML // fx:id="graph"
    private Pane graph; // Value injected by FXMLLoader

@FXML // fx:id="saveButton"
    private Button saveButton; // Value injected by FXMLLoader

// ...

@FXML
    void clickSave(ActionEvent event) {
        Stage yourStage = (Stage) saveButton.getScene().getWindow();

        FileChooser fileChooser = new FileChooser();
        fileChooser.setInitialDirectory(new File("Path\\With\\Spaces"));
        fileChooser.getExtensionFilters().add(new FileChooser.ExtensionFilter("BMP Files", "*.bmp"));

        // Show save dialog
        File file = fileChooser.showSaveDialog(yourStage);

        if (file != null) {
            if (!file.exists()) {
                try {
                    Files.createFile(file.toPath());
                } catch (IOException e) {
                    e.printStackTrace(); // Handle the exception
                }
            }

            WritableImage writableImage = graph.snapshot(new SnapshotParameters(), null);
            BufferedImage bufferedImage = SwingFXUtils.fromFXImage(writableImage, null);

            try {
                ImageIO.write(bufferedImage, "BMP", file);

                // Inform the user about the successful save
                Alert alert = new Alert(Alert.AlertType.INFORMATION);
                alert.setTitle("File Saved");
                alert.setHeaderText(null);
                alert.setContentText("The file has been saved successfully.");
                alert.showAndWait();
            } catch (IOException e) {
                e.printStackTrace();

                // Inform the user about the error
                Alert alert = new Alert(Alert.AlertType.ERROR);
                alert.setTitle("Error");
                alert.setHeaderText(null);
                alert.setContentText("An error occurred while saving the file.");
                alert.showAndWait();
            }
        }
    }

编辑: 按照@James_D的注释建议，我将代码更改为以下代码，但问题仍然存在.

@FXML
    void clickSave(ActionEvent event) {
        Stage stage = (Stage) saveButton.getScene().getWindow();

        FileChooser fileChooser = new FileChooser();
        fileChooser.setInitialDirectory(new File("Path\\With\\Spaces"));
        fileChooser.getExtensionFilters().add(new FileChooser.ExtensionFilter("BMP Files", "*.bmp"));

        // Show save dialog
        File file = fileChooser.showSaveDialog(stage);

        if (file != null) {
            WritableImage writableImage = graph.snapshot(new SnapshotParameters(), null);
            BufferedImage bufferedImage = SwingFXUtils.fromFXImage(writableImage, null);

            try {
                ImageIO.write(bufferedImage, "BMP", file);

                if (!file.exists()) {
                    Files.createFile(file.toPath());
                }

                // Inform the user about the successful save
                Alert alert = new Alert(Alert.AlertType.INFORMATION);
                alert.setTitle("File Saved");
                alert.setHeaderText(null);
                alert.setContentText("The file has been saved successfully.");
                alert.showAndWait();
            } catch (IOException e) {
                e.printStackTrace();

                // Inform the user about the error
                Alert alert = new Alert(Alert.AlertType.ERROR);
                alert.setTitle("Error");
                alert.setHeaderText(null);
                alert.setContentText("An error occurred while saving the file.");
                alert.showAndWait();
            }
        }
    }