我正在研究JavaFX项目来管理锻炼。虽然它有一个大的.fxml文件和一个大的MainController类，但它运行良好：
WorkoutsMain.fxml：
<AnchorPane id="AnchorPane" fx:id="anchorPane" prefHeight="900.0" prefWidth="1600.0" xmlns="http://javafx.com/javafx/8" xmlns:fx="http://javafx.com/fxml/1" fx:controller="workouts.WorkoutsMainController">
<children>
<SplitPane fx:id="splitPane" dividerPositions="0.15" AnchorPane.bottomAnchor="0.0" AnchorPane.leftAnchor="0.0" AnchorPane.rightAnchor="0.0" AnchorPane.topAnchor="0.0">
<items>
<AnchorPane>
<children>
<StackPane fx:id="menuPane" AnchorPane.bottomAnchor="0.0" AnchorPane.leftAnchor="0.0" AnchorPane.rightAnchor="0.0" AnchorPane.topAnchor="0.0"/>
</children>
</AnchorPane>
<AnchorPane>
<children>
<Pane fx:id="statisticsPane" visible="false" AnchorPane.bottomAnchor="0.0" AnchorPane.leftAnchor="0.0" AnchorPane.rightAnchor="0.0" AnchorPane.topAnchor="130.0"/>
<Pane fx:id="workoutsPane" visible="false" AnchorPane.bottomAnchor="0.0" AnchorPane.leftAnchor="0.0" AnchorPane.rightAnchor="0.0" AnchorPane.topAnchor="130.0">
//... other FX elements
</Pane>
<Pane fx:id="calendarPane" AnchorPane.bottomAnchor="0.0" AnchorPane.leftAnchor="0.0" AnchorPane.rightAnchor="0.0" AnchorPane.topAnchor="130.0"/>
<StackPane fx:id="logoPane" onmouseclicked="#setLogo" AnchorPane.bottomAnchor="778.0" AnchorPane.leftAnchor="0.0" AnchorPane.rightAnchor="0.0" AnchorPane.topAnchor="0.0"/>
</children>
</AnchorPane>
</items>
</SplitPane>
</children>
</AnchorPane>
WorkoutsMainController.java：
public class WorkoutsMainController implements Initializable,SplitPaneDividerController {
private final DataBase dataBase = new DataBase();
private boolean first = true;
private String logoName;
@FXML
private StackPane logoPane,menuPane;
private final List<Pane> panes = new ArrayList<>();
@FXML
private Pane calendarPane,workoutsPane,statisticsPane;
@FXML
private SplitPane splitPane;
@FXML
private AnchorPane anchorPane;
// methods and functions
@Override
public void initialize(URL url,ResourceBundle rb) {
setLogo();
disableSplitPaneDivider(splitPane,0.1525);
setUpMainmenu();
}
}
MainClass.java：
public class MainClass extends Application {
private Parent anchorPane;
private final String fxml = "WorkoutsMain.fxml";
@Override
public void start(Stage stage) {
try {
anchorPane = FXMLLoader.load(getclass().getResource(fxml));
} catch (IOException ex) {
System.out.println("Error when trying to load " + fxml);
}
Scene scene = new Scene(anchorPane);
stage.setScene(scene);
stage.getIcons().add(new Image(getclass().getResourceAsStream("/calendarIconWhite.png")));
stage.setTitle("THE WORKOUT CALENDAR 1.7.0 by hazazs®");
stage.setResizable(false);
stage.show();
}
public static void main(String[] args) {
launch(args);
}
}
然后我想从WorkoutsMain.fxml中切出一块。我已经在原始的.fxml大文件中更改了一段，如下所示：
来自
<Pane fx:id="workoutsPane" visible="false" AnchorPane.bottomAnchor="0.0" AnchorPane.leftAnchor="0.0" AnchorPane.rightAnchor="0.0" AnchorPane.topAnchor="130.0">
//... other FX elements
</Pane>
到
<fx:include source="Workouts.fxml" fx:id="workoutsPane"/>
然后，我用其自己的Controller类创建了一个新的fxml文件：
Workouts.fxml：
<Pane fx:id="workoutsPane" visible="false" AnchorPane.bottomAnchor="0.0" AnchorPane.leftAnchor="0.0" AnchorPane.rightAnchor="0.0" AnchorPane.topAnchor="130.0" xmlns:fx="http://javafx.com/fxml/1" fx:controller="workouts.WorkoutsController">
// other FX elements
</Pane>
我已经创建了一个适当的WorkoutsController类，并且已经如下更改了WorkoutsMainController：
public class WorkoutsMainController implements Initializable,SplitPaneDividerController {
protected static final DataBase dataBase = new DataBase();
private final WorkoutsController workoutsController = new WorkoutsController();
private boolean first = true;
private String logoName;
@FXML
private StackPane logoPane,statisticsPane;
@FXML
protected static SplitPane splitPane;
@FXML
protected static AnchorPane anchorPane;
// and so on..
但是从现在开始，当我尝试启动我的应用程序时，我得到了异常：
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$159(LauncherImpl.java:182)
at java.lang.Thread.run(Thread.java:748)
Caused by: java.lang.NullPointerException: Root cannot be null
at javafx.scene.Scene.<init>(Scene.java:336)
at javafx.scene.Scene.<init>(Scene.java:194)
at workouts.MainClass.start(MainClass.java:23)
at com.sun.javafx.application.LauncherImpl.lambda$launchApplication1$166(LauncherImpl.java:863)
at com.sun.javafx.application.PlatformImpl.lambda$runAndWait$179(PlatformImpl.java:326)
at com.sun.javafx.application.PlatformImpl.lambda$null$177(PlatformImpl.java:295)
at java.security.accessController.doPrivileged(Native Method)
at com.sun.javafx.application.PlatformImpl.lambda$runLater$178(PlatformImpl.java:294)
at com.sun.glass.ui.InvokeLaterDispatcher$Future.run(InvokeLaterDispatcher.java:95)
at com.sun.glass.ui.win.WinApplication._runLoop(Native Method)
at com.sun.glass.ui.win.WinApplication.lambda$null$152(WinApplication.java:177)
... 1 more
任何建议者，我应该怎么做才能再次进行这项工作？使用一个.fxml和一个Controller可以完美地工作。
谢谢