java - 为什么我在io.datafx中得到java.lang.NullPointerException？

我发现了JAVAFX，并实现了项目结构的重构
1小时后，也许这很愚蠢，但实际上我不明白问题所在。
在围绕名称和包文件进行重构之前，它可以正常工作。
我的项目现在处于Maven之下（我不知道这是否有所改变）
这是我的错误：

GRAVE: null
io.datafx.controller.flow.FlowException: io.datafx.controller.FxmlLoadException: java.lang.reflect.InvocationTargetException
    at io.datafx.controller.flow.FlowHandler.start(FlowHandler.java:143)
    at io.datafx.controller.flow.FlowHandler.start(FlowHandler.java:101)
    at maxiRename.controller.MainController.initialize(MainController.java:88)
    at javafx.fxml.FXMLLoader.loadImpl(FXMLLoader.java:2548)
    at javafx.fxml.FXMLLoader.loadImpl(FXMLLoader.java:2441)
    at javafx.fxml.FXMLLoader.load(FXMLLoader.java:2409)
    at io.datafx.controller.ViewFactory.createByController(ViewFactory.java:161)
    at io.datafx.controller.flow.FlowHandler.start(FlowHandler.java:140)
    at maxiRenameApp.MainMaxiFilm.start(MainMaxiFilm.java:27)
    at com.sun.javafx.application.LauncherImpl.lambda$launchApplication1$162(LauncherImpl.java:863)
    at com.sun.javafx.application.PlatformImpl.lambda$runAndWait$175(PlatformImpl.java:326)
    at com.sun.javafx.application.PlatformImpl.lambda$null$173(PlatformImpl.java:295)
    at java.security.AccessController.doPrivileged(Native Method)
    at com.sun.javafx.application.PlatformImpl.lambda$runLater$174(PlatformImpl.java:294)
    at com.sun.glass.ui.InvokeLaterDispatcher$Future.run(InvokeLaterDispatcher.java:95)
    at com.sun.glass.ui.win.WinApplication._runLoop(Native Method)
    at com.sun.glass.ui.win.WinApplication.lambda$null$148(WinApplication.java:191)
    at java.lang.Thread.run(Thread.java:745)
Caused by: io.datafx.controller.FxmlLoadException: java.lang.reflect.InvocationTargetException
    at io.datafx.controller.ViewFactory.createByController(ViewFactory.java:180)
    at io.datafx.controller.flow.FlowHandler.start(FlowHandler.java:140)
    ... 17 more
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 io.datafx.controller.ViewFactory.createByController(ViewFactory.java:175)
    ... 18 more
Caused by: java.lang.NullPointerException
    at maxiRename.controller.SideMenuController.init(SideMenuController.java:65)
    ... 23 more

这是我的sidebarMenuController.java：

package maxiRename.controller;

import javax.annotation.PostConstruct;

import com.jfoenix.controls.JFXListView;

import io.datafx.controller.FXMLController;
import io.datafx.controller.flow.Flow;
import io.datafx.controller.flow.FlowException;
import io.datafx.controller.flow.FlowHandler;
import io.datafx.controller.flow.context.FXMLViewFlowContext;
import io.datafx.controller.flow.context.ViewFlowContext;
import io.datafx.controller.util.VetoException;
import javafx.fxml.FXML;
import javafx.scene.Node;
import javafx.scene.control.Label;
import javafx.scene.image.ImageView;
import javafx.scene.layout.StackPane;
import javafx.scene.layout.VBox;

@FXMLController(value = "/maxiRename/view/SideMenu.fxml", title = "Material Design Example")
public class SideMenuController {


    @FXML
    private StackPane root;

    @FXML
    private VBox listViewDrawer;

    @FXML
    private ImageView imageTopDrawer;

    @FXML
    private JFXListView<?> list1;

    @FXML
    private Label home;

    @FXML
    private JFXListView<?> subList;

    @FXML
    private Label musics;

    @FXML
    private Label movies;

    @FXML
    private Label series;

    @FXML
    private Label help;

    @FXML
    private Label exit;

    @FXMLViewFlowContext
    private ViewFlowContext context;

    @PostConstruct
    public void init() throws FlowException, VetoException {
        list1.propagateMouseEventsToParent();
        System.out.println(context);
        FlowHandler contentFlowHandler = (FlowHandler) context.getRegisteredObject("ContentFlowHandler");
        Flow contentFlow = (Flow) context.getRegisteredObject("ContentFlow");
        System.out.println(subList.getItems().get(0));
        bindNodeToController(home, HomeController.class, contentFlow, contentFlowHandler);
        bindNodeToController(musics, MusicsSettingsController.class, contentFlow, contentFlowHandler);
        bindNodeToController(movies, MoviesSettingsController.class, contentFlow, contentFlowHandler);
        bindNodeToController(series, SeriesSettingsController.class, contentFlow, contentFlowHandler);
        bindNodeToController(help, HelpController.class, contentFlow, contentFlowHandler);
    }

    private void bindNodeToController(Node node, Class<?> controllerClass, Flow flow, FlowHandler flowHandler) {
        flow.withGlobalLink(node.getId(), controllerClass);
        node.setOnMouseClicked((e) -> {
            try {
                flowHandler.handle(node.getId());
            } catch (Exception e1) {
                e1.printStackTrace();
            }
        });
    }
}

我的结构文件是否可以帮助您：


我的第一个想法是在错误的路径或类似的路径上，但是如果我更改它，则会收到错误“未设置位置”，因此我想这里的路径很好。

@FXMLController(value = "/maxiRename/view/SideMenu.fxml", title = "Material Design Example")

编辑：maxiRename.controller.SideMenuController.init（SideMenuController.java:65）是：

FlowHandler contentFlowHandler = (FlowHandler) context.getRegisteredObject("ContentFlowHandler");
and context is null

最佳答案

好，我找到了！

它是名为“流”的库。在8.0版中可以使用，但在8.1版中不能使用。

从行家我有这个：

<dependency>
    <groupId>io.datafx</groupId>
    <artifactId>flow</artifactId>
    <version>8.1</version>
</dependency>

现在我有这个：

<dependency>
        <groupId>io.datafx</groupId>
        <artifactId>flow</artifactId>
        <version>8.0</version>
    </dependency>

谢谢，我希望这对其他人有用；）