java.lang.NullPointerException：位置为必需。 Netbeans 8.2

Question

我试图让我的JavaFX程序在按下按钮时在屏幕之间切换，但是我遇到了困难。 我收到一长串错误消息，其中之一是“ java.lang.NullPointerException：必须提供位置”。 我对该程序的所有文件都保存在同一软件包中。

主要方法：

package therealcompsciia;  

import javafx.application.Application;
import javafx.fxml.FXMLLoader;
import javafx.scene.Parent;
import javafx.scene.Scene;
import javafx.stage.Stage;

public class TheRealCompSciIA extends Application {

    @Override
    public void start(Stage stage) throws Exception {
        Parent root = FXMLLoader.load(getClass().getResource("NewSoccerAppInitialScreen.fxml"));

        Scene scene = new Scene(root);

        stage.setScene(scene);
        stage.show();
    }
/**
 * @param args the command line arguments
 */
public static void main(String[] args) {
    launch(args);
}

}

这是初始屏幕FXML的代码，NewSoccerAppInitialScreen.fxml

<?xml version="1.0" encoding="UTF-8"?>

<?import javafx.scene.control.Button?>
<?import javafx.scene.control.Label?>
<?import javafx.scene.image.Image?>
<?import javafx.scene.image.ImageView?>
<?import javafx.scene.layout.AnchorPane?>
<?import javafx.scene.text.Font?>

<AnchorPane maxHeight="-Infinity" maxWidth="-Infinity" minHeight="-Infinity" minWidth="-Infinity" prefHeight="336.0" prefWidth="456.0" xmlns="http://javafx.com/javafx/8.0.111" xmlns:fx="http://javafx.com/fxml/1" fx:controller="NewSoccerAppInitialScreenController"> 
  <children>
  <Button fx:id="PlayerProfiles" alignment="CENTER" layoutX="15.0" layoutY="148.0" mnemonicParsing="false" onAction="#playerprofilesButton" prefHeight="90.0" prefWidth="134.0" text="Player Profiles" textFill="#bf1616">
     <font>
        <Font size="14.0" />
     </font></Button>
  <Button fx:id="Statistics" alignment="CENTER" layoutX="162.0" layoutY="148.0" mnemonicParsing="false" onAction="#statisticsButton" prefHeight="90.0" prefWidth="134.0" text="Statistics" textFill="#bf1616">
     <font>
        <Font size="14.0" />
     </font>
  </Button>
  <Button fx:id="FormationEditor" alignment="CENTER" layoutX="308.0" layoutY="148.0" mnemonicParsing="false" onAction="#formationeditorButton" prefHeight="90.0" prefWidth="134.0" text="Formation Editor" textFill="#bf1616">
     <font>
        <Font size="14.0" />
     </font>
  </Button>
  <ImageView fitHeight="98.0" fitWidth="198.0" layoutY="238.0" pickOnBounds="true" preserveRatio="true">
     <image>
        <Image url="@CompSci%20IA%20Grass.jpe" />
     </image>
  </ImageView>
  <ImageView fitHeight="98.0" fitWidth="198.0" layoutX="135.0" layoutY="238.0" pickOnBounds="true" preserveRatio="true">
     <image>
        <Image url="@CompSci%20IA%20Grass.jpe" />
     </image>
  </ImageView>
  <ImageView fitHeight="98.0" fitWidth="198.0" layoutX="255.0" layoutY="238.0" pickOnBounds="true" preserveRatio="true">
     <image>
        <Image url="@CompSci%20IA%20Grass.jpe" />
     </image>
  </ImageView>
  <ImageView fitHeight="98.0" fitWidth="198.0" layoutX="316.0" layoutY="238.0" pickOnBounds="true" preserveRatio="true">
     <image>
        <Image url="@CompSci%20IA%20Grass.jpe" />
     </image>
  </ImageView>
  <ImageView fitHeight="78.0" fitWidth="107.0" layoutX="296.0" layoutY="76.0" pickOnBounds="true" preserveRatio="true">
     <image>
        <Image url="@CompSci%20IA%20Goal.jpe" />
     </image>
  </ImageView>
  <ImageView fitHeight="98.0" fitWidth="64.0" layoutX="63.0" layoutY="73.0" pickOnBounds="true" preserveRatio="true">
     <image>
        <Image url="@CompSci%20IA%20Soccer%20Ball.jpe" />
     </image>
  </ImageView>
  <Label layoutX="114.0" layoutY="30.0" text="DM Soccer Manager" textFill="#bf1616">
     <font>
        <Font name="System Bold" size="24.0" />
     </font>
  </Label>
  </children>
  </AnchorPane>

这是我的初始屏幕控制器NewSoccerAppInitialScreenController.java的代码

import java.io.IOException;
import java.net.URL;
import java.util.ResourceBundle;
import javafx.event.ActionEvent;
import javafx.fxml.FXML;
import javafx.fxml.FXMLLoader;
import javafx.fxml.Initializable;
import javafx.scene.Node;
import javafx.scene.Parent;
import javafx.scene.Scene;
import javafx.scene.control.Button;
import javafx.stage.Stage;

public class NewSoccerAppInitialScreenController implements Initializable {

@FXML
private Button PlayerProfiles;
@FXML
private Button Statistics;
@FXML
private Button FormationEditor;

    @FXML
    private void formationeditorButton(ActionEvent event) throws IOException{
    Parent FXMLDocument2Parent = FXMLLoader.load(getClass().getClassLoader().getResource("fxml_NewFormationsInitialScreen.fxml"));
    Scene FXMLDocument2Scene = new Scene(FXMLDocument2Parent);
    Stage AppStage = (Stage) ((Node) event.getSource()).getScene().getWindow();
    //AppStage.hide();
    AppStage.setScene(FXMLDocument2Scene);
    AppStage.show();
    }

    @FXML
    private void playerprofilesButton(ActionEvent event) throws IOException{
    Parent FXMLDocument2Parent = FXMLLoader.load(getClass().getClassLoader().getResource("fxml_NewPlayerProfilesInitial.fxml"));
    Scene FXMLDocument2Scene = new Scene(FXMLDocument2Parent);
    Stage AppStage = (Stage) ((Node) event.getSource()).getScene().getWindow();
    //AppStage.hide();
    AppStage.setScene(FXMLDocument2Scene);
    AppStage.show();
    }

    @FXML
    private void statisticsButton(ActionEvent event) throws IOException{
    Parent FXMLDocument2Parent = FXMLLoader.load(getClass().getClassLoader().getResource("fxml_NewStatisticsInitial.fxml"));
    Scene FXMLDocument2Scene = new Scene(FXMLDocument2Parent);
    Stage AppStage = (Stage) ((Node) event.getSource()).getScene().getWindow();
    //AppStage.hide();
    AppStage.setScene(FXMLDocument2Scene);
    AppStage.show();
    }


@Override
public void initialize(URL url, ResourceBundle rb) {
    // TODO
}    

}

这是错误消息：

Exception in thread "JavaFX Application Thread" java.lang.RuntimeException: java.lang.reflect.InvocationTargetException
at javafx.fxml.FXMLLoader$MethodHandler.invoke(FXMLLoader.java:1774)
at javafx.fxml.FXMLLoader$ControllerMethodEventHandler.handle(FXMLLoader.java:1657)
at com.sun.javafx.event.CompositeEventHandler.dispatchBubblingEvent(CompositeEventHandler.java:86)
at com.sun.javafx.event.EventHandlerManager.dispatchBubblingEvent(EventHandlerManager.java:238)
at com.sun.javafx.event.EventHandlerManager.dispatchBubblingEvent(EventHandlerManager.java:191)
at com.sun.javafx.event.CompositeEventDispatcher.dispatchBubblingEvent(CompositeEventDispatcher.java:59)
at com.sun.javafx.event.BasicEventDispatcher.dispatchEvent(BasicEventDispatcher.java:58)
at com.sun.javafx.event.EventDispatchChainImpl.dispatchEvent(EventDispatchChainImpl.java:114)
at com.sun.javafx.event.BasicEventDispatcher.dispatchEvent(BasicEventDispatcher.java:56)
at com.sun.javafx.event.EventDispatchChainImpl.dispatchEvent(EventDispatchChainImpl.java:114)
at com.sun.javafx.event.BasicEventDispatcher.dispatchEvent(BasicEventDispatcher.java:56)
at com.sun.javafx.event.EventDispatchChainImpl.dispatchEvent(EventDispatchChainImpl.java:114)
at com.sun.javafx.event.EventUtil.fireEventImpl(EventUtil.java:74)
at com.sun.javafx.event.EventUtil.fireEvent(EventUtil.java:49)
at javafx.event.Event.fireEvent(Event.java:198)
at javafx.scene.Node.fireEvent(Node.java:8413)
at javafx.scene.control.Button.fire(Button.java:185)
at com.sun.javafx.scene.control.behavior.ButtonBehavior.mouseReleased(ButtonBehavior.java:182)
at com.sun.javafx.scene.control.skin.BehaviorSkinBase$1.handle(BehaviorSkinBase.java:96)
at com.sun.javafx.scene.control.skin.BehaviorSkinBase$1.handle(BehaviorSkinBase.java:89)
at com.sun.javafx.event.CompositeEventHandler$NormalEventHandlerRecord.handleBubblingEvent(CompositeEventHandler.java:218)
at com.sun.javafx.event.CompositeEventHandler.dispatchBubblingEvent(CompositeEventHandler.java:80)
at com.sun.javafx.event.EventHandlerManager.dispatchBubblingEvent(EventHandlerManager.java:238)
at com.sun.javafx.event.EventHandlerManager.dispatchBubblingEvent(EventHandlerManager.java:191)
at com.sun.javafx.event.CompositeEventDispatcher.dispatchBubblingEvent(CompositeEventDispatcher.java:59)
at com.sun.javafx.event.BasicEventDispatcher.dispatchEvent(BasicEventDispatcher.java:58)
at com.sun.javafx.event.EventDispatchChainImpl.dispatchEvent(EventDispatchChainImpl.java:114)
at com.sun.javafx.event.BasicEventDispatcher.dispatchEvent(BasicEventDispatcher.java:56)
at com.sun.javafx.event.EventDispatchChainImpl.dispatchEvent(EventDispatchChainImpl.java:114)
at com.sun.javafx.event.BasicEventDispatcher.dispatchEvent(BasicEventDispatcher.java:56)
at com.sun.javafx.event.EventDispatchChainImpl.dispatchEvent(EventDispatchChainImpl.java:114)
at com.sun.javafx.event.EventUtil.fireEventImpl(EventUtil.java:74)
at com.sun.javafx.event.EventUtil.fireEvent(EventUtil.java:54)
at javafx.event.Event.fireEvent(Event.java:198)
at javafx.scene.Scene$MouseHandler.process(Scene.java:3757)
at javafx.scene.Scene$MouseHandler.access$1500(Scene.java:3485)
at javafx.scene.Scene.impl_processMouseEvent(Scene.java:1762)
at javafx.scene.Scene$ScenePeerListener.mouseEvent(Scene.java:2494)
at com.sun.javafx.tk.quantum.GlassViewEventHandler$MouseEventNotification.run(GlassViewEventHandler.java:381)
at com.sun.javafx.tk.quantum.GlassViewEventHandler$MouseEventNotification.run(GlassViewEventHandler.java:295)
at java.security.AccessController.doPrivileged(Native Method)
at com.sun.javafx.tk.quantum.GlassViewEventHandler.lambda$handleMouseEvent$354(GlassViewEventHandler.java:417)
at com.sun.javafx.tk.quantum.QuantumToolkit.runWithoutRenderLock(QuantumToolkit.java:389)
at com.sun.javafx.tk.quantum.GlassViewEventHandler.handleMouseEvent(GlassViewEventHandler.java:416)
at com.sun.glass.ui.View.handleMouseEvent(View.java:555)
at com.sun.glass.ui.View.notifyMouse(View.java:937)
at com.sun.glass.ui.win.WinApplication._runLoop(Native Method)
at com.sun.glass.ui.win.WinApplication.lambda$null$148(WinApplication.java:191)
at java.lang.Thread.run(Thread.java:745)
Caused by: java.lang.reflect.InvocationTargetException
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:498)
at sun.reflect.misc.Trampoline.invoke(MethodUtil.java:71)
at sun.reflect.GeneratedMethodAccessor1.invoke(Unknown Source)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:498)
at sun.reflect.misc.MethodUtil.invoke(MethodUtil.java:275)
at javafx.fxml.FXMLLoader$MethodHandler.invoke(FXMLLoader.java:1769)
... 48 more
Caused by: java.lang.NullPointerException: Location is required.
at javafx.fxml.FXMLLoader.loadImpl(FXMLLoader.java:3207)
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 NewSoccerAppInitialScreenController.formationeditorButton(NewSoccerAppInitialScreenController.java:37)
... 58 more

我不确定是什么问题。 文件名正确，并且都存在于同一项目下的同一程序包中。 我的初始屏幕已加载并且可见，但是，一旦我单击其中一个按钮将我发送到新屏幕，就会显示上面的错误消息。

Answer 1

您的问题似乎与那些问题2相同：

• JavaFX“位置是必需的。” 即使在同一包装中

• 加载FXML文件时出现“需要位置”异常