运行javafx程序时InvocationTargetException

Question

因此，这在我的电脑具有jdk 1.7.0的javafx示例中起作用，因此，这可能是java8中FX的新版本。

我得到了很好的堆栈跟踪

jfx-project-run:
Executing E:\workspace\PathFinderApp\dist\run1095471771\PathFinderApp.jar using platform C:\Program Files\Java\jdk1.8.0\jre/bin/java
Exception in Application start method
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:483)
    at com.sun.javafx.application.LauncherImpl.launchApplicationWithArgs(LauncherImpl.java:367)
    at com.sun.javafx.application.LauncherImpl.launchApplication(LauncherImpl.java:305)
    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:483)
    at sun.launcher.LauncherHelper$FXHelper.main(LauncherHelper.java:767)
Caused by: java.lang.RuntimeException: Exception in Application start method
    at com.sun.javafx.application.LauncherImpl.launchApplication1(LauncherImpl.java:894)
    at com.sun.javafx.application.LauncherImpl.access$000(LauncherImpl.java:56)
    at com.sun.javafx.application.LauncherImpl$1.run(LauncherImpl.java:158)
    at java.lang.Thread.run(Thread.java:744)
Caused by: javafx.fxml.LoadException: 
file:/E:/workspace/PathFinderApp/dist/run1095471771/PathFinderApp.jar!/com/rpg/gui/main.fxml:11

    at javafx.fxml.FXMLLoader.constructLoadException(FXMLLoader.java:2617)
    at javafx.fxml.FXMLLoader.access$700(FXMLLoader.java:104)
    at javafx.fxml.FXMLLoader$ValueElement.processAttribute(FXMLLoader.java:937)
    at javafx.fxml.FXMLLoader$InstanceDeclarationElement.processAttribute(FXMLLoader.java:976)
    at javafx.fxml.FXMLLoader$Element.processStartElement(FXMLLoader.java:216)
    at javafx.fxml.FXMLLoader$ValueElement.processStartElement(FXMLLoader.java:738)
    at javafx.fxml.FXMLLoader.processStartElement(FXMLLoader.java:2723)
    at javafx.fxml.FXMLLoader.loadImpl(FXMLLoader.java:2527)
    at javafx.fxml.FXMLLoader.loadImpl(FXMLLoader.java:2441)
    at javafx.fxml.FXMLLoader.loadImpl(FXMLLoader.java:3230)
    at javafx.fxml.FXMLLoader.loadImpl(FXMLLoader.java:3191)
    at javafx.fxml.FXMLLoader.loadImpl(FXMLLoader.java:3164)
    at javafx.fxml.FXMLLoader.loadImpl(FXMLLoader.java:3140)
    at javafx.fxml.FXMLLoader.loadImpl(FXMLLoader.java:3120)
    at javafx.fxml.FXMLLoader.load(FXMLLoader.java:3113)
    at com.rpg.gui.GUI.loadMainPane(GUI.java:34)
    at com.rpg.gui.GUI.initialize(GUI.java:20)
    at Main.start(Main.java:20)
    at com.sun.javafx.application.LauncherImpl$8.run(LauncherImpl.java:837)
    at com.sun.javafx.application.PlatformImpl$7.run(PlatformImpl.java:335)
    at com.sun.javafx.application.PlatformImpl$6$1.run(PlatformImpl.java:301)
    at com.sun.javafx.application.PlatformImpl$6$1.run(PlatformImpl.java:298)
    at java.security.AccessController.doPrivileged(Native Method)
    at com.sun.javafx.application.PlatformImpl$6.run(PlatformImpl.java:298)
    at com.sun.glass.ui.InvokeLaterDispatcher$Future.run(InvokeLaterDispatcher.java:95)
    at com.sun.glass.ui.win.WinApplication._runLoop(Native Method)
    at com.sun.glass.ui.win.WinApplication.access$300(WinApplication.java:39)
    at com.sun.glass.ui.win.WinApplication$4$1.run(WinApplication.java:112)
    ... 1 more
Caused by: java.lang.InstantiationException: com.rpg.gui.MainController
    at java.lang.Class.newInstance(Class.java:418)
    at sun.reflect.misc.ReflectUtil.newInstance(ReflectUtil.java:51)
    at javafx.fxml.FXMLLoader$ValueElement.processAttribute(FXMLLoader.java:932)
    ... 26 more
Caused by: java.lang.NoSuchMethodException: com.rpg.gui.MainController.<init>()
    at java.lang.Class.getConstructor0(Class.java:2971)
    at java.lang.Class.newInstance(Class.java:403)
    ... 28 more
Exception running application Main
Java Result: 1

基本上告诉我这里有问题 "com/rpg/gui/main.fxml:11"

那条线是

<AnchorPane id="AnchorPane" prefHeight="400.0" prefWidth="600.0" xmlns:fx="http://javafx.com/fxml" fx:controller="com.rpg.gui.MainController">

因此我可以弄清楚它与主控制器无关，因此必须与加载fxml和控制器有关？但这就是我的想法的结局

MainController mainController = new MainController(path);
Pane mainPane = FXMLLoader.load(getClass().getResource("main.fxml"));
Window.setMainController(mainController);
Window.swap(path+"content.fxml");

这就是它的方法，它将把所有东西扔给任何有javaFX经验的人，或者知道java8中有任何变化的人会这样做吗？

Answer 1

您MainController没有零参数的构造函数。如果在根元素上FXMLLoader遇到一个fx:controller属性，它将尝试通过（有效）调用该属性中指定的类的零参数构造函数来创建该控制器的实例。

要解决此问题（最简单的方法），请 从FXML文件中
删除该fx:controller属性，然后在上“手动”设置控制器FXMLLoader。您需要创建一个FXMLLoader实例，而不是依赖于静态load(...)方法：

FXMLLoader loader = new FXMLLoader(getClass().getResource("main.fxml"));
loader.setController(new MainController(path));
Pane mainPane = loader.load();