我刚刚开始使用JavaFX并在尝试加载我的一个FXML文件时遇到问题，即使我在同一个过程中设置了所有这些文件，也就是＃34; SinglePlayer.fxml＆＃34;该程序被假定为Tic-Tac-Toe游戏，并在＆＃34; coopAction＆＃34;事件开始了。 这是我的MasterWindow.java：我对这个类的想法是抽象出所有要由这一类控制的控制器。
public class MasterWindow {
protected Stage window;
protected Scene currentScene,loginScene,homeScreen,settingScreen,singleplayerScreen;
protected Parent root,loginSceneParent,homeSceneParent,settingSceneParent,singleplayerSceneParent;
//protected MediaBox mediaBox = new MediaBox();
public MasterWindow(){
System.out.println("Ceated MasterWindow");
}
public MasterWindow(Stage otherWindow){
window = otherWindow;
try {
connectToLogin();
} catch (IOException e){e.printStackTrace();}
window.setTitle("Tic-Tac-Claw");
window.setMinWidth(450);
window.setMaxWidth(650);
window.setMinHeight(500);
window.setMaxHeight(600);
window.setWidth(500);
window.setHeight(550);
}
public void closeProgram(Stage window) {
boolean result = ExitBox.display("Alert Window", "Do you really want to leave?");
if (result) {
System.out.println("Saving files...");
//mediaBox.getMediaPlayer().stop();
window.close();
}
}
protected void connectToSingle() throws IOException {
singleplayerSceneParent = FXMLLoader.load(getClass().getResource("/singlePlayer.fxml"));
//(MasterWindow.java:50) above
settingScreen = new Scene(singleplayerSceneParent);
settingScreen.getStylesheets().add("/singlePlayer.css");
}
protected void connectToSetting() throws IOException {
settingSceneParent = FXMLLoader.load(getClass().getResource("/settingScreen.fxml"));
settingScreen = new Scene(settingSceneParent);
settingScreen.getStylesheets().add("/settingScreen.css");
}
protected void connectToHome() throws IOException{
homeSceneParent = FXMLLoader.load(getClass().getResource("/homeScreen.fxml"));
homeScreen = new Scene(homeSceneParent);
homeScreen.getStylesheets().add("/homeScreen.css");
}
protected void connectToLogin() throws IOException{
loginSceneParent = FXMLLoader.load(getClass().getResource("/loginScreen.fxml"));
loginScene = new Scene(loginSceneParent);
loginScene.getStylesheets().add("/login.css");
}
homeScreenController.java：这是打开合作游戏的事件开始的地方
public class homeScreenController extends MasterWindow{
@FXML
private Button coopButton,multiplayerButton,settingButton,exitButton;
public homeScreenController(){
System.out.println("Created home");
}
public void coopAction(ActionEvent event) throws IOException {
System.out.println("User press Co-op");
window = (Stage)((Node)event.getSource()).getScene().getWindow();
window.setScene(singleplayerScreen);
this.connectToSingle(); //(homeScreenController.java:40)
window.show();
}
这是游戏，singlePlayer.java：
public class singlePlayer extends MasterWindow implements Initializable{
...
@FXML
private Pane pane;
public singlePlayer(){
//this.start();
}
@Override
public void initialize(URL location, ResourceBundle resources) {
pane.setPrefSize(1000,1000);
for(int y=0;y< board.length;y++){
for(int x=0;x<board.length;x++){
Tile tile = new Tile();
tile.setTranslateX(x*200);
tile.setTranslateY(y*200);
pane.getChildren().add(tile);
board[x][y] = tile;
}
}
//window.setScene(singleplayerScreen);
//this.getWindow().setHeight(1000);
//this.getWindow().setWidth(1000);
window.show(); //(singlePlayer.java:52)
}
FXML文件，singlePlayer.fxml
<?import javafx.scene.layout.Pane?>
<Pane fx:id="pane" maxHeight="-Infinity" maxWidth="-Infinity" minHeight="-Infinity" minWidth="-Infinity" prefHeight="400.0" prefWidth="600.0" xmlns="http://javafx.com/javafx/8.0.141" xmlns:fx="http://javafx.com/fxml/1" fx:controller="edu.baylor.ecs.singlePlayer">
</Pane>
堆栈跟踪：
Ceated MasterWindow
User press Login button
Ceated MasterWindow
Created home
User press Co-op
Ceated MasterWindow
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$353(GlassViewEventHandler.java:417)
at com.sun.javafx.tk.quantum.QuantumToolkit.runWithoutRenderLock(QuantumToolkit.java:389)
at com.sun.javafx.tk.quantum.GlassViewEventHandler.handleMouseEvent(GlassViewEventHandler.java:416)
at com.sun.glass.ui.View.handleMouseEvent(View.java:555)
at com.sun.glass.ui.View.notifyMouse(View.java:937)
at com.sun.glass.ui.win.WinApplication._runLoop(Native Method)
at com.sun.glass.ui.win.WinApplication.lambda$null$147(WinApplication.java:177)
at java.lang.Thread.run(Thread.java:748)
Caused by: java.lang.reflect.InvocationTargetException
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:498)
at sun.reflect.misc.Trampoline.invoke(MethodUtil.java:71)
at sun.reflect.GeneratedMethodAccessor1.invoke(Unknown Source)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:498)
at sun.reflect.misc.MethodUtil.invoke(MethodUtil.java:275)
at javafx.fxml.FXMLLoader$MethodHandler.invoke(FXMLLoader.java:1769)
... 48 more
Caused by: javafx.fxml.LoadException:
/K:/IntelliJ/Projects/TicTacClaw/target/classes/singlePlayer.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 edu.baylor.ecs.MasterWindow.connectToSingle(MasterWindow.java:50)
at edu.baylor.ecs.homeScreenController.coopAction(homeScreenController.java:40)
... 58 more
Caused by: java.lang.NullPointerException
at edu.baylor.ecs.singlePlayer.initialize(singlePlayer.java:52)
at javafx.fxml.FXMLLoader.loadImpl(FXMLLoader.java:2548)
... 67 more
该项目有一个资源文件夹，里面包含所有FXML和CSS文件，所有其他场景更改都能正常工作。如果您有任何建议或解决方案，任何事情都会有所帮助！
编辑：该行＆＃34; singleplayerSceneParent = FXMLLoader.load（getClass（）。getResource（＆＃34; /singlePlayer.fxml"））;＆＃34;是什么抛出IOException并且设置与其他FXMLLoader完全一样。其他方法都是偶然的，或者我错过了JavaFX中显而易见的东西。我查看了sample example，我理解NullPointerException是如何发生的，但是在我给它资源之前我不会调用singleplayerSceneParent。
答案 0 :(得分：0)
您的异常似乎可能在堆栈跟踪的最后部分：
Caused by: java.lang.NullPointerException
at edu.baylor.ecs.singlePlayer.initialize(singlePlayer.java:52)
在 singlePlayer 类的初始化方法中，您需要迭代矩阵，直到y< board.length和x< board.length。其中一个不应该是board.width吗？