JavaFX:thread中的异常；JavaFX应用程序线程；java.lang.RuntimeException:java.lang.reflect.InvocationTargetException

我尝试重新浏览category列表以在tableView中显示它，但当我在控制器中插入CategoryService时遇到了一个异常，这是代码的一部分， 当我单击onbtnActionCategory时，主控制器将包含一个操作，以使用stackPane切换场景的一部分。场景的一部分应随新视图而更改

@Controller
public class HomeController implements Initializable {
    @FXML
    private StackPane stackPaneHolder;

    public void setPane(Node node) {
        if (stackPaneHolder.getChildren().isEmpty()) {
            //if stackPaneHolder is empty
            stackPaneHolder.getChildren().add(node);

        } else {
            if (stackPaneHolder.getClip() != node) {
                //if stackPaneHolder is not empty then remove existing layer and add new layer
                stackPaneHolder.getChildren().remove(0);
                stackPaneHolder.getChildren().add(0, node);
            }
        }
    }


    public void onBtnActionDashboard(ActionEvent event) throws IOException {
        Node change = FXMLLoader.load(getClass().getResource("/fxml/home.fxml"));
        setPane(change);
    }
    public void onBtnActionCategory(ActionEvent event) throws IOException {
        Node change = FXMLLoader.load(getClass().getResource("/fxml/category.fxml"));
        setPane(change);
    }

    @Override
    public void initialize(URL location, ResourceBundle resources) {

    }
} 

我的分类电脑 但是，当initialize方法调用witch时，我调用CategoryService来重现数据，对象为Null

@Controller
public class CategoryController implements Initializable {

    @Autowired
     CategoryService categoryService;

    @FXML
    private TableView<Category> categoryTable;
    @FXML
    private TableColumn<Category, String> colCategorie;

    @FXML
    private TableColumn<Category, String> colDescription;

    private ObservableList<Category> categoryList = FXCollections.observableArrayList();


    @Override
    public void initialize(URL location, ResourceBundle resources) {
        categoryTable.getSelectionModel().setSelectionMode(SelectionMode.MULTIPLE);
        setColumnProperties();
        loadCategoryDetails();
    }

    private void setColumnProperties() {
        colCategorie.setCellValueFactory(new PropertyValueFactory<>("Category"));
        colDescription.setCellValueFactory(new PropertyValueFactory<>("Description"));

    }

    /*
     *  Add All category to observable list and update table
     */
    private void loadCategoryDetails(){
        categoryList.clear();

        categoryList.addAll(categoryService.findAll());

        categoryTable.setItems(categoryList);

    }
}

---

控制器实例不是使用spring的

BeanFactory

创建的。因此，未注入

@Autowired

值。您需要告诉

FXMLLoader

使用

BeanFactory

创建控制器：

public void onBtnActionCategory(ActionEvent event) throws IOException {
    FXMLLoader loader = new FXMLLoader(getClass().getResource("/fxml/category.fxml"));
    loader.setControllerFactory(context::getBean);
    Node change = loader.load();
    setPane(change);
}

当然，要实现这一点，您需要确保

BeanFactory上下文

字段可用（通常使用

ApplicationContext

初始化）。以下线程中提供了几种初始化此类字段的选项：

如果您使用与上面类似的代码加载所有FXML，您应该能够通过spring简单地注入该值

at com.sun.javafx.tk.quantum.GlassViewEventHandler.handleMouseEvent(GlassViewEventHandler.java:431)
    at com.sun.glass.ui.View.handleMouseEvent(View.java:555)
    at com.sun.glass.ui.View.notifyMouse(View.java:937)
    at com.sun.glass.ui.win.WinApplication._runLoop(Native Method)
    at com.sun.glass.ui.win.WinApplication.lambda$null$147(WinApplication.java:177)
    at java.lang.Thread.run(Thread.java:748)
Caused by: java.lang.reflect.InvocationTargetException
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
    at java.lang.reflect.Method.invoke(Method.java:498)
    at sun.reflect.misc.Trampoline.invoke(MethodUtil.java:71)
    at sun.reflect.GeneratedMethodAccessor28.invoke(Unknown Source)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
    at java.lang.reflect.Method.invoke(Method.java:498)
    at sun.reflect.misc.MethodUtil.invoke(MethodUtil.java:275)
    at javafx.fxml.FXMLLoader$MethodHandler.invoke(FXMLLoader.java:1769)
    ... 48 more
Caused by: javafx.fxml.LoadException: 
/C:/Desktop/JFXSB/gestionStock/target/classes/fxml/category.fxml

    at javafx.fxml.FXMLLoader.constructLoadException(FXMLLoader.java:2601)
    at javafx.fxml.FXMLLoader.loadImpl(FXMLLoader.java:2579)
    at javafx.fxml.FXMLLoader.loadImpl(FXMLLoader.java:2441)
    at javafx.fxml.FXMLLoader.loadImpl(FXMLLoader.java:3214)
    at javafx.fxml.FXMLLoader.loadImpl(FXMLLoader.java:3175)
    at javafx.fxml.FXMLLoader.loadImpl(FXMLLoader.java:3148)
    at javafx.fxml.FXMLLoader.loadImpl(FXMLLoader.java:3124)
    at javafx.fxml.FXMLLoader.loadImpl(FXMLLoader.java:3104)
    at javafx.fxml.FXMLLoader.load(FXMLLoader.java:3097)
    at com.gestionStock.controller.HomeController.onBtnActionCategory(HomeController.java:40)
    ... 58 more
Caused by: java.lang.NullPointerException
    at com.gestionStock.controller.CategoryController.loadCategoryDetails(CategoryController.java:57)
    at com.gestionStock.controller.CategoryController.initialize(CategoryController.java:42)
    at javafx.fxml.FXMLLoader.loadImpl(FXMLLoader.java:2548)
    ... 66 more```

public void onBtnActionCategory(ActionEvent event) throws IOException {
    FXMLLoader loader = new FXMLLoader(getClass().getResource("/fxml/category.fxml"));
    loader.setControllerFactory(context::getBean);
    Node change = loader.load();
    setPane(change);
}