在FXML中創建的JavaFX中設置BorderPane的中心窗格（nullPointerException）

Question

我現在花了一些時間試圖弄清楚我的邏輯在哪里有缺陷，並在這里看到了類似的問題，但是由於某些原因，我一直在獲取nullPointerException：

public class MainWindowController
    implements Initializable {


    public static final String SCHEDULE_MANAGER = "ScheduleManagerController";
    public static final URL SCHEDULE_MANAGER_FXML = ScheduleManagerController.class.getResource("ScheduleManager.fxml");
    final SwitchableStackPane customStackPane = new SwitchableStackPane();

    @FXML 
    Button btnScheduleManager; // Value injected by FXMLLoader
    BorderPane switchablePane; //Value injected by FXMLLoader


    @Override // This method is called by the FXMLLoader when initialization is complete
    public void initialize(URL fxmlFileLocation, ResourceBundle resources) {
        assert btnScheduleManager != null : "fx:id=\"ScheduleManager\" was not injected: check your FXML file 'HOECTool.fxml'.";
        assert switchablePane != null : "fx:id=\"mainPane\" was not injected: check your FXML file 'HOECTool.fxml'.";


            customStackPane.loadScreen(SCHEDULE_MANAGER, SCHEDULE_MANAGER_FXML);

            switchablePane.setCenter(customStackPane);

    }

這將引發nullPointer異常：switchablePane.setCenter（customStackPane）;

Answer 1

排序，我是個白痴。 做到了：

 @FXML 
    Button btnScheduleManager; // Value injected by FXMLLoader
@FXML
    BorderPane switchablePane; //Value injected by FXMLLoader