java FX-编辑选项的问题是我的java fx应用程序

Question

I have an issue with my java app regarding below method:

private void clearFields() {
this.clientComboBox.getSelectionModel().clearSelection();
this.segmentComboBox.getSelectionModel().clearSelection();
this.releaseDatePicker.getEditor().clear();
this.titleTextField.clear();
this.priceTextField.clear();
this.basepriceTextField.clear();
this.descTextArea.clear();
this.vinTextField.clear();
this.daysSlider.setValue(1);

}

When I try to add a Car there is no issue, program runs perfectly. But when I try to click edit option , after saving changes, each column for edited row set as empty, what I do wrong?

link to my repo: https://github.com/tomekcm4/wypozyczalnia.git

apparently something is wrong with this part:

this.editColumn.setCellFactory(param -> new TableCell<CarFx, CarFx>() {
        Button button = createButton("/icons/edit.png");

        @Override
        protected void updateItem(CarFx item, boolean empty) {
            super.updateItem(item, empty);

            if (empty) {
                setGraphic(null);
                return;
            }

            if (!empty) {
                setGraphic(button);
                button.setOnAction(event -> {
                    FXMLLoader loader = FxmlUtils.getLoader("/fxml/AddCar.fxml");
                    Scene scene = null;
                    try {
                        scene = new Scene(loader.load());
                    } catch (IOException e) {
                        DialogsUtils.errorDialog(e.getMessage());
                    }
                    CarController controller = loader.getController();
                    controller.getCarModel().setCarFxObjectProperty(item);
                    controller.bindings();

                    Stage stage = new Stage();
                    stage.setScene(scene);
                    stage.initModality(Modality.APPLICATION_MODAL);
                    stage.showAndWait();
                });
            }
        }
    });

}

save button looks like this:

public void addCarOnAction() {
    try {
        this.carModel.saveCarInDataBase();

        clearFields();




    } catch (ApplicationException e) {
        DialogsUtils.errorDialog(e.getMessage());
    }


}