我在Javafx程序中切换了两个场景。但是当我按下特定按钮时，我会听到以下错误： -
"C:\Program Files\Java\jdk1.8.0_66\bin\java" -Didea.launcher.port=7532 "-Didea.launcher.bin.path=C:\Program Files (x86)\JetBrains\IntelliJ IDEA Community Edition 15.0.2\bin" -Dfile.encoding=UTF-8 -classpath "C:\Program Files\Java\jdk1.8.0_66\jre\lib\charsets.jar;C:\Program Files\Java\jdk1.8.0_66\jre\lib\deploy.jar;C:\Program Files\Java\jdk1.8.0_66\jre\lib\ext\access-bridge-64.jar;C:\Program Files\Java\jdk1.8.0_66\jre\lib\ext\cldrdata.jar;C:\Program Files\Java\jdk1.8.0_66\jre\lib\ext\dnsns.jar;C:\Program Files\Java\jdk1.8.0_66\jre\lib\ext\jaccess.jar;C:\Program Files\Java\jdk1.8.0_66\jre\lib\ext\jfxrt.jar;C:\Program Files\Java\jdk1.8.0_66\jre\lib\ext\localedata.jar;C:\Program Files\Java\jdk1.8.0_66\jre\lib\ext\nashorn.jar;C:\Program Files\Java\jdk1.8.0_66\jre\lib\ext\sunec.jar;C:\Program Files\Java\jdk1.8.0_66\jre\lib\ext\sunjce_provider.jar;C:\Program Files\Java\jdk1.8.0_66\jre\lib\ext\sunmscapi.jar;C:\Program Files\Java\jdk1.8.0_66\jre\lib\ext\sunpkcs11.jar;C:\Program Files\Java\jdk1.8.0_66\jre\lib\ext\zipfs.jar;C:\Program Files\Java\jdk1.8.0_66\jre\lib\javaws.jar;C:\Program Files\Java\jdk1.8.0_66\jre\lib\jce.jar;C:\Program Files\Java\jdk1.8.0_66\jre\lib\jfr.jar;C:\Program Files\Java\jdk1.8.0_66\jre\lib\jfxswt.jar;C:\Program Files\Java\jdk1.8.0_66\jre\lib\jsse.jar;C:\Program Files\Java\jdk1.8.0_66\jre\lib\management-agent.jar;C:\Program Files\Java\jdk1.8.0_66\jre\lib\plugin.jar;C:\Program Files\Java\jdk1.8.0_66\jre\lib\resources.jar;C:\Program Files\Java\jdk1.8.0_66\jre\lib\rt.jar;C:\ZeusPortal\Java\Lesson6\out\production\Lesson6;C:\Program Files (x86)\JetBrains\IntelliJ IDEA Community Edition 15.0.2\lib\idea_rt.jar" com.intellij.rt.execution.application.AppMain Intro5
Exception in thread "JavaFX Application Thread" java.lang.IllegalArgumentException: Children: cycle detected: parent = VBox@6e07849a, node = VBox@6e07849a
at javafx.scene.Parent$2.onProposedChange(Parent.java:445)
at com.sun.javafx.collections.VetoableListDecorator.addAll(VetoableListDecorator.java:234)
at com.sun.javafx.collections.VetoableListDecorator.addAll(VetoableListDecorator.java:103)
at popup.showing(popup.java:25)
at Intro5.lambda$start$0(Intro5.java:21)
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:8411)
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$MouseEventNotification.run(GlassViewEventHandler.java:352)
at com.sun.javafx.tk.quantum.GlassViewEventHandler$MouseEventNotification.run(GlassViewEventHandler.java:275)
at java.security.AccessController.doPrivileged(Native Method)
at com.sun.javafx.tk.quantum.GlassViewEventHandler.lambda$handleMouseEvent$354(GlassViewEventHandler.java:388)
at com.sun.javafx.tk.quantum.QuantumToolkit.runWithoutRenderLock(QuantumToolkit.java:389)
at com.sun.javafx.tk.quantum.GlassViewEventHandler.handleMouseEvent(GlassViewEventHandler.java:387)
at com.sun.glass.ui.View.handleMouseEvent(View.java:555)
at com.sun.glass.ui.View.notifyMouse(View.java:937)
at com.sun.glass.ui.win.WinApplication._runLoop(Native Method)
at com.sun.glass.ui.win.WinApplication.lambda$null$148(WinApplication.java:191)
at java.lang.Thread.run(Thread.java:745)
我在两个不同的班级中使用两个不同场景的两个阶段。我在按下按钮时切换这两个场景，出现在我的主要班级中。
Mainclass
import javafx.application.Application;
import javafx.scene.Scene;
import javafx.scene.control.Button;
import javafx.scene.control.Label;
import javafx.scene.layout.VBox;
import javafx.stage.Stage;
public class MainClass extends Application{
public static void main(String[] args) {launch(args);}
public void start(Stage Mystage) throws Exception{
Mystage.setTitle("Primary Stages!");
Label lbl = new Label("This is Scene of a primary Stage.");
Button btn = new Button("Click me!");
btn.setOnAction(e -> popup.showing("Pop-up Window","This Pop-Up window is extremely awesome."));
VBox layout = new VBox();
layout.getChildren().addAll(lbl,btn);
Scene sn = new Scene(layout,400,400);
Mystage.setScene(sn);
Mystage.show();
}
}
第二场景类
import javafx.geometry.Pos;
import javafx.scene.control.Button;
import javafx.scene.control.Label;
import javafx.scene.layout.VBox;
import javafx.stage.*;
import javafx.scene.*;
public class popup {
public static void showing(String title, String Message){
Stage stg = new Stage();
stg.initModality(Modality.APPLICATION_MODAL);
stg.setTitle(title);
stg.setMinWidth(300);
Label lbl = new Label();
lbl.setText(Message);
Button btn = new Button("Close!");
btn.setOnAction(e -> stg.close());
VBox layout = new VBox();
layout.getChildren().addAll(layout,btn);
layout.setAlignment(Pos.CENTER);
Scene sn = new Scene(layout,500,500);
stg.setScene(sn);
stg.showAndWait();
}
}
这是我的整个情景。当我应该点击我的主类中的按钮时，会出现一个弹出阶段，显示一些消息。这个弹出阶段在我弹出的课程中编程。但每当我点击我的主类中的按钮时，就会出现上面提到的异常（实际上是一堆错误），终止我的应用程序。如果可能，请帮助我。 JavaFX是非常复杂的库，我刚刚开始使用它。我不习惯这个图书馆。
答案 0 :(得分：1)
您将VBox置于其中。改变这一行：
layout.getChildren().addAll(layout,btn);
到
layout.getChildren().addAll(lbl,btn);
（在弹出窗口中）。