我无法加载启动方法，因此应用程序将无法启动。
因此，我有一个名为StAnnesApp的主类，该主类运行代码并具有start方法。还创建了一个主控制器类来控制我如何在所有场景之间切换。
我正在为此项目使用Scene Builder，所以我有一个LoginController类，应在其中加载应用程序并作为第一页打开，并在其中获取错误。
这是StAnnesApp.java
package st.annesapp;
import javafx.application.Application;
import javafx.fxml.FXMLLoader;
import javafx.scene.Group;
import javafx.scene.Parent;
import javafx.scene.Scene;
import javafx.stage.Stage;
import Controllers.LoginMainController;
import Controllers.MainMenuController;
public class StAnnesApp extends Application {
private static MainController mainScreen;
public static MainController getMenu()
{
return mainScreen;
}
private Group root;
@Override
public void start(Stage primaryStage) {
try {
Group group = new Group();
mainScreen = new MainController(group);
Scene scene = new Scene(group);
mainScreen.startApp();
primaryStage.setResizable(false);
primaryStage.setScene(scene);
primaryStage.show();
} catch (Exception e) {
e.printStackTrace();
}
}
/**
* @param args the command line arguments
*/
public static void main(String[] args) {
launch(args);
}
}
这是MainController.java（之所以称为Main controller，是因为它正在控制其他控制器类）
package st.annesapp;
public class MainController extends Parent
{
private final Group root;
private LoginMainController loginMain;
private MainMenuController mainMenu;
public MainController (Group _group)
{
this.root = _group;
}
public void startApp()
{
loginMain = new LoginMainController();
root.getChildren().addAll(loginMain);
}
public void changeScreen (int screenNumber)
{
switch (screenNumber)
{
case 1:
root.getChildren().remove(loginMain);
loginMain = null;
mainMenu = new MainMenuController();
root.getChildren().add(mainMenu);
break;
case 2:
root.getChildren().remove(mainMenu);
mainMenu = null;
}
}
}
这是LoginMainController.java（这是我收到错误的地方）
package Controllers;
import java.io.File;
import java.net.URL;
import java.util.ResourceBundle;
import javafx.fxml.FXML;
import javafx.fxml.Initializable;
import javafx.scene.control.Button;
import javafx.scene.control.PasswordField;
import javafx.scene.control.TextField;
import java.io.IOException;
import static java.rmi.server.RMIClassLoader.getClassLoader;
import java.util.logging.Level;
import java.util.logging.Logger;
import javafx.event.ActionEvent;
import javafx.fxml.FXMLLoader;
import javafx.scene.Parent;
import st.annesapp.StAnnesApp;
public class LoginMainController extends Parent implements Initializable {
@FXML
private TextField lblUser;
@FXML
private PasswordField lblPass;
@FXML
private Button btnLogin;
@Override
public void initialize(URL url, ResourceBundle rb)
{
}
public LoginMainController()
{
addNodesToLayout();
logIn();
}
@FXML
public void buttonAction(ActionEvent e)
{
if (lblUser.getText().equals("dorset"))
{
StAnnesApp.getMenu().changeScreen(1);
}
}
private void logIn ()
{
lblPass = new PasswordField();
lblUser = new TextField();
btnLogin = new Button();
}
private void addNodesToLayout ()
{
try {
Parent root = XMLLoader.load(getClass().getResource("/FXML/LoginMain.fxml"));
getChildren().add(root);
} catch (IOException ex) {
Logger.getLogger(LoginMainController.class.getName()).log(Level.SEVERE, null, ex);
}
}
}
这是我从中得到的错误。
ant -f "C:\\Users\\paulo\\Documents\\Multimedia Application\\St.AnnesApp" jfxsa-run
init:
Deleting: C:\Users\paulo\Documents\Multimedia Application\St.AnnesApp\build\built-jar.properties
deps-jar:
Updating property file: C:\Users\paulo\Documents\Multimedia Application\St.AnnesApp\build\built-jar.properties
Compiling 1 source file to C:\Users\paulo\Documents\Multimedia Application\St.AnnesApp\build\classes
compile:
Deleting directory C:\Users\paulo\Documents\Multimedia Application\St.AnnesApp\dist\lib
Copying 2 files to C:\Users\paulo\Documents\Multimedia Application\St.AnnesApp\dist\lib
Detected JavaFX Ant API version 1.3
Launching <fx:jar> task from C:\Program Files\Java\jdk1.8.0_131\jre\..\lib\ant-javafx.jar
Warning: From JDK7u25 the Codebase manifest attribute should be used to restrict JAR repurposing.
Please set manifest.custom.codebase property to override the current default non-secure value '*'.
Launching <fx:deploy> task from C:\Program Files\Java\jdk1.8.0_131\jre\..\lib\ant-javafx.jar
No base JDK. Package will use system JRE.
No base JDK. Package will use system JRE.
jfx-deployment-script:
jfx-deployment:
jar:
Copying 14 files to C:\Users\paulo\Documents\Multimedia Application\St.AnnesApp\dist\run1928276430
jfx-project-run:
Executing C:\Users\paulo\Documents\Multimedia Application\St.AnnesApp\dist\run1928276430\St.AnnesApp.jar using platform C:\Program Files\Java\jdk1.8.0_131\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:498)
at com.sun.javafx.application.LauncherImpl.launchApplicationWithArgs(LauncherImpl.java:389)
at com.sun.javafx.application.LauncherImpl.launchApplication(LauncherImpl.java:328)
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.launcher.LauncherHelper$FXHelper.main(LauncherHelper.java:767)
Caused by: java.lang.RuntimeException: Exception in Application start method
at com.sun.javafx.application.LauncherImpl.launchApplication1(LauncherImpl.java:917)
at com.sun.javafx.application.LauncherImpl.lambda$launchApplication$155(LauncherImpl.java:182)
at java.lang.Thread.run(Thread.java:748)
Caused by: java.lang.StackOverflowError
at java.util.concurrent.ConcurrentHashMap.putIfAbsent(ConcurrentHashMap.java:1535)
at java.lang.ClassLoader.getClassLoadingLock(ClassLoader.java:463)
at java.lang.ClassLoader.loadClass(ClassLoader.java:404)
at sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:335)
at java.lang.ClassLoader.loadClass(ClassLoader.java:357)
at sun.reflect.GeneratedConstructorAccessor2.newInstance(Unknown Source)
at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:45)
at java.lang.reflect.Constructor.newInstance(Constructor.java:423)
at java.lang.Class.newInstance(Class.java:442)
at sun.reflect.misc.ReflectUtil.newInstance(ReflectUtil.java:51)
at javafx.fxml.FXMLLoader$ValueElement.processAttribute(FXMLLoader.java:927)
at javafx.fxml.FXMLLoader$InstanceDeclarationElement.processAttribute(FXMLLoader.java:971)
at
javafx.fxml.FXMLLoader$Element.processStartElement(FXMLLoader.java:220)
at
javafx.fxml.FXMLLoader$ValueElement.processStartElement(FXMLLoader.java:744)
at javafx.fxml.FXMLLoader.processStartElement(FXMLLoader.java:2707)
at javafx.fxml.FXMLLoader.loadImpl(FXMLLoader.java:2527)
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
Controllers.LoginMainController.addNodesToLayout(LoginMainController.java:110)
at Controllers.LoginMainController.<init>(LoginMainController.java:68)
这是LoginMain.fxml类
<?xml version="1.0" encoding="UTF-8"?>
<?import javafx.scene.control.Button?>
<?import javafx.scene.control.Label?>
<?import javafx.scene.control.PasswordField?>
<?import javafx.scene.control.TextField?>
<?import javafx.scene.image.Image?>
<?import javafx.scene.image.ImageView?>
<?import javafx.scene.layout.AnchorPane?>
<?import javafx.scene.text.Font?>
<AnchorPane id="AnchorPane" fx:id="root" prefHeight="400.0" prefWidth="600.0" style="-fx-background-color: #2D3447;" xmlns="http://javafx.com/javafx/10.0.1" xmlns:fx="http://javafx.com/fxml/1" >
<children>
<TextField fx:id="lblUser" layoutX="192.0" layoutY="180.0" prefHeight="26.0" prefWidth="220.0" promptText="Username" />
<PasswordField fx:id="lblPass" layoutX="190.0" layoutY="229.0" prefHeight="26.0" prefWidth="220.0" promptText="Password" />
<Button fx:id="btnLogin" layoutX="241.0" layoutY="288.0" mnemonicParsing="false" onAction="#buttonAction" prefHeight="32.0" prefWidth="123.0" text="Login" />
<ImageView fitHeight="112.0" fitWidth="157.0" layoutX="244.0" layoutY="14.0" pickOnBounds="true" preserveRatio="true">
<image>
<Image url="@../Images/woods-marker.png" />
</image>
</ImageView>
<Label layoutX="227.0" layoutY="144.0" prefHeight="27.0" prefWidth="183.0" text="St.Annes Park App" textFill="#fff2f2">
<font>
<Font size="18.0" />
</font>
</Label>
</children>
</AnchorPane>