Javafx 2 使用控制器更改与单选按钮一起使用的css文件

好的，这是我第一次使用Javafx和Scene Builder，但我遇到了一个无法解决的问题

基本上，我正在制作一个应用程序，其中包括一个设置选项卡，用户可以使用单选按钮更改应用程序的颜色主题（即带有浅色背景的浅色主题、按钮、选项卡、文本字段等）。因此，如果用户单击“light”单选按钮，它应该加载“light”css文件，如果选择了“dark”单选按钮，它应该更改为使用“dark”css文件，等等

在控制器类中，我有以下内容：

@FXML
RadioButton rbtnLight;
@FXML
public void colourThemeLight(javafx.event.ActionEvent event)
{ 
 if (rbtnLight.isSelected() == true)
    {
        System.out.println("I'm the chosen button");
        //I'm using println at the moment to test that it's actually recognizing the action performed
    }
}

 @FXML
RadioButton rbtnDark;
 @FXML
public void colourThemeDark(javafx.event.ActionEvent event)
{ 
 if (rbtnDark.isSelected() == true)
    {
        System.out.println("I'm the other chosen button");
        //Again, I'm using println at the moment to test that it's actually recognizing the action performed
    }
}

File file = new File("path");
String css1 = file.toString();
mainS.getStyleClass().add(css1); //mainS being the main screen in sceneBuilder which everything is placed on

但它给出了一个“RuntimeException:java.lang.reflect.InvocationTargetException” 由

if（rbtnLight.isSelected（）=true）

和

if（rbtnLight.isSelected（）=true）

语句处的NullPointerException引起

我还尝试使用了

rbtnLight.isDisabled（）==false

和

.isPressed（）==true

但是两者都给出了相同的错误。 或者，我尝试了

if（event.getSource（）==rbtnTLightS）

，但实际上没有任何作用。没有错误，但也没有消息

在场景生成器中，我已将样式表加载到主窗口，而不是“设置”选项卡中的单个单选按钮

（差不多完成了……）

如果这样做成功，我将如何加载正确的css文件？我找到了一种方法，如下所示：

@FXML
RadioButton rbtnLight;
@FXML
public void colourThemeLight(javafx.event.ActionEvent event)
{ 
 if (rbtnLight.isSelected() == true)
    {
        System.out.println("I'm the chosen button");
        //I'm using println at the moment to test that it's actually recognizing the action performed
    }
}

 @FXML
RadioButton rbtnDark;
 @FXML
public void colourThemeDark(javafx.event.ActionEvent event)
{ 
 if (rbtnDark.isSelected() == true)
    {
        System.out.println("I'm the other chosen button");
        //Again, I'm using println at the moment to test that it's actually recognizing the action performed
    }
}

File file = new File("path");
String css1 = file.toString();
mainS.getStyleClass().add(css1); //mainS being the main screen in sceneBuilder which everything is placed on

但我怀疑这是否有效

如果您能提供任何帮助，我们将不胜感激。对于这篇文章，我深表歉意：）

编辑：完成堆栈跟踪-

Exception in thread "JavaFX Application Thread" java.lang.RuntimeException: java.lang.reflect.InvocationTargetException
at javafx.fxml.FXMLLoader$MethodHandler.invoke(FXMLLoader.java:1770)
at javafx.fxml.FXMLLoader$ControllerMethodEventHandler.handle(FXMLLoader.java:1653)
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.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:8390)
at javafx.scene.control.ToggleButton.fire(ToggleButton.java:256)
at javafx.scene.control.RadioButton.fire(RadioButton.java:113)
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.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$MouseHandler.process(Scene.java:3758)
at javafx.scene.Scene$MouseHandler.access$1500(Scene.java:3486)
at javafx.scene.Scene.impl_processMouseEvent(Scene.java:1762)
at javafx.scene.Scene$ScenePeerListener.mouseEvent(Scene.java:2495)
at com.sun.javafx.tk.quantum.GlassViewEventHandler$MouseEventNotification.run(GlassViewEventHandler.java:350)
at com.sun.javafx.tk.quantum.GlassViewEventHandler$MouseEventNotification.run(GlassViewEventHandler.java:275)
at java.security.AccessController.doPrivileged(Native Method)
at com.sun.javafx.tk.quantum.GlassViewEventHandler.lambda$handleMouseEvent$350(GlassViewEventHandler.java:385)
at com.sun.javafx.tk.quantum.GlassViewEventHandler$$Lambda$257/436071628.get(Unknown Source)
at com.sun.javafx.tk.quantum.QuantumToolkit.runWithoutRenderLock(QuantumToolkit.java:404)
at com.sun.javafx.tk.quantum.GlassViewEventHandler.handleMouseEvent(GlassViewEventHandler.java:384)
at com.sun.glass.ui.View.handleMouseEvent(View.java:555)
at com.sun.glass.ui.View.notifyMouse(View.java:927)
at com.sun.glass.ui.win.WinApplication._runLoop(Native Method)
at com.sun.glass.ui.win.WinApplication.lambda$null$145(WinApplication.java:101)
at com.sun.glass.ui.win.WinApplication$$Lambda$36/1963387170.run(Unknown Source)
at java.lang.Thread.run(Thread.java:745)
Caused by: java.lang.reflect.InvocationTargetException
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:497)
at sun.reflect.misc.Trampoline.invoke(MethodUtil.java:71)
at sun.reflect.GeneratedMethodAccessor1.invoke(Unknown Source)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:497)
at sun.reflect.misc.MethodUtil.invoke(MethodUtil.java:275)
at javafx.fxml.FXMLLoader$MethodHandler.invoke(FXMLLoader.java:1765)
... 59 more
Caused by: java.lang.NullPointerException
at settings.FXMLDocumentController.colourThemeLight(FXMLDocumentController.java:75)
... 69 more

我发布的加载不同css文件的方法有效吗

没有

将不起作用，因为getStyleClass（）接受CSS样式表文件中定义的CSS选择器，而不是其路径或名称

应该是

mainS.getStyleSheets().add(css1);

---

请参阅。

能否添加完整的堆栈跟踪？从您发布的内容来看，我认为，

rbtnLight

仍然是空的，您将得到一个

NullPointerException

@ItachiUchiha Added:）请确保FXML文件中的单选按钮具有正确的fx:id。@UlukBiy啊，废话。。。外汇：我再次得到我。。。别忘了它。现在它已经识别了一个动作，我发布的加载不同css文件的方法是否有效？还是我把它添加到了错误的项目中？哇，谢谢！我在root.getChildren（）上遇到了一个错误，

error:getChildren（）在父级中具有受保护的访问权限

my Parent是一个拆分窗格。我已经读到这可能是一个原因，但我没有一个边框窗格作为一个选项来包装它，并将其放入锚点，网格或堆栈窗格似乎也不起作用。建议？@Grey，对于splitpane，它应该是root.getItems（）。请参阅拆分窗格javadoc。