尝试运行 java fx 应用程序时出现“FXMLLoader.constructLoadException”
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"FXMLLoader.constructLoadException" when trying to run java fx application
提问by PooBucket
I already searched the deepest depths of the interweb but no answer will seem to be found -.-
我已经搜索了互联网的最深处,但似乎找不到答案-.-
The problem is in my javaFx programm i want to write. But i can't make it any further than adding the controller class. I followed nearly every tutorial a could find, but the issue still remains unknown to me.
问题出在我想编写的 javaFx 程序中。但除了添加控制器类之外,我不能再做任何事情了。我遵循了几乎所有可以找到的教程,但我仍然不知道这个问题。
This is the exception:
这是例外:
javafx.fxml.LoadException:
/U:/BankingSolutions/MediaCenterFX/bin/main/ressources/view/MainUI.fxml:12
at javafx.fxml.FXMLLoader.constructLoadException(FXMLLoader.java:2617)
at javafx.fxml.FXMLLoader.access0(FXMLLoader.java:104)
at javafx.fxml.FXMLLoader$ValueElement.processAttribute(FXMLLoader.java:927)
at javafx.fxml.FXMLLoader$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 application.Main.start(Main.java:15)
at com.sun.javafx.application.LauncherImpl.run(LauncherImpl.java:837)
at com.sun.javafx.application.PlatformImpl.run(PlatformImpl.java:335)
at com.sun.javafx.application.PlatformImpl.run(PlatformImpl.java:301)
at com.sun.javafx.application.PlatformImpl.run(PlatformImpl.java:298)
at java.security.AccessController.doPrivileged(Native Method)
at com.sun.javafx.application.PlatformImpl.run(PlatformImpl.java:298)
at com.sun.glass.ui.InvokeLaterDispatcher$Future.run(InvokeLaterDispatcher.java:95)
at com.sun.glass.ui.win.WinApplication._runLoop(Native Method)
at com.sun.glass.ui.win.WinApplication.access0(WinApplication.java:39)
at com.sun.glass.ui.win.WinApplication.run(WinApplication.java:112)
at java.lang.Thread.run(Thread.java:745)
Caused by: java.lang.ClassNotFoundException: /java/controllers/MainUIController
at java.net.URLClassLoader.run(URLClassLoader.java:372)
at java.net.URLClassLoader.run(URLClassLoader.java:361)
at java.security.AccessController.doPrivileged(Native Method)
at java.net.URLClassLoader.findClass(URLClassLoader.java:360)
at java.lang.ClassLoader.loadClass(ClassLoader.java:424)
at sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:308)
at java.lang.ClassLoader.loadClass(ClassLoader.java:357)
at javafx.fxml.FXMLLoader$ValueElement.processAttribute(FXMLLoader.java:925)
... 24 more
and this is the code. there are thre classes: The Main.class, my MainUI.fxml which i created using scenebuilder 2 and my MainUIController.class which should obviously work as the mainuis controller
这是代码。有三个类:Main.class,我使用scenebuilder 2 创建的MainUI.fxml 和我的MainUIController.class,它显然应该作为mainuis 控制器工作
package application;
import javafx.application.Application;
import javafx.fxml.FXMLLoader;
import javafx.stage.Stage;
import javafx.scene.Scene;
import javafx.scene.layout.AnchorPane;
public class Main extends Application {
@Override
public void start(Stage primaryStage) {
try {
AnchorPane root = (AnchorPane) FXMLLoader.load(getClass().getResource("/main/ressources/view/MainUI.fxml"));
Scene scene = new Scene(root);
primaryStage.setScene(scene);
primaryStage.show();
} catch(Exception e) {
e.printStackTrace();
}
}
public static void main(String[] args) {
launch(args);
}
}
_______________________________________________
<?xml version="1.0" encoding="UTF-8"?>
<?import javafx.scene.text.*?>
<?import javafx.scene.control.*?>
<?import javafx.scene.*?>
<?import javafx.geometry.*?>
<?import javafx.scene.image.*?>
<?import java.lang.*?>
<?import javafx.scene.layout.*?>
<?import javafx.scene.layout.AnchorPane?>
<AnchorPane fx:id="root" prefHeight="1080.0" prefWidth="1920.0" xmlns="http://javafx.com/javafx/8" xmlns:fx="http://javafx.com/fxml/1" fx:controller="/java/controllers/MainUIController">
<children>
<BorderPane fx:id="borderPane01" layoutX="657.0" layoutY="304.0" prefHeight="336.0" prefWidth="403.0" AnchorPane.bottomAnchor="0.0" AnchorPane.leftAnchor="0.0" AnchorPane.rightAnchor="0.0" AnchorPane.topAnchor="0.0">
<bottom>
<AnchorPane fx:id="bp_bottom" prefHeight="200.0" prefWidth="200.0" BorderPane.alignment="CENTER" />
</bottom>
<left>
<GridPane fx:id="bp_left_grid" prefHeight="680.0" prefWidth="238.0" BorderPane.alignment="CENTER">
<columnConstraints>
<ColumnConstraints hgrow="SOMETIMES" minWidth="10.0" prefWidth="100.0" />
<ColumnConstraints hgrow="SOMETIMES" minWidth="10.0" prefWidth="100.0" />
<ColumnConstraints hgrow="SOMETIMES" minWidth="10.0" prefWidth="100.0" />
</columnConstraints>
<rowConstraints>
<RowConstraints minHeight="10.0" prefHeight="30.0" vgrow="SOMETIMES" />
<RowConstraints minHeight="10.0" prefHeight="30.0" vgrow="SOMETIMES" />
<RowConstraints minHeight="10.0" prefHeight="30.0" vgrow="SOMETIMES" />
<RowConstraints minHeight="10.0" prefHeight="30.0" vgrow="SOMETIMES" />
<RowConstraints minHeight="10.0" prefHeight="30.0" vgrow="SOMETIMES" />
<RowConstraints minHeight="10.0" prefHeight="30.0" vgrow="SOMETIMES" />
<RowConstraints minHeight="10.0" prefHeight="30.0" vgrow="SOMETIMES" />
</rowConstraints>
<children>
<Button fx:id="btn_search" mnemonicParsing="false" prefHeight="48.0" prefWidth="172.0" text="Suche" GridPane.columnSpan="2147483647" GridPane.halignment="CENTER" GridPane.hgrow="ALWAYS" GridPane.valignment="CENTER">
<GridPane.margin>
<Insets />
</GridPane.margin>
<font>
<Font size="24.0" />
</font>
</Button>
<Button fx:id="btn_series" mnemonicParsing="false" prefHeight="48.0" prefWidth="172.0" text="Serien" wrapText="true" GridPane.columnSpan="3" GridPane.halignment="CENTER" GridPane.rowIndex="1" GridPane.valignment="CENTER">
<font>
<Font size="24.0" />
</font>
</Button>
<Button fx:id="btn_download" mnemonicParsing="false" prefHeight="48.0" prefWidth="172.0" text="Download" GridPane.columnSpan="3" GridPane.halignment="CENTER" GridPane.rowIndex="3" GridPane.valignment="CENTER">
<font>
<Font size="24.0" />
</font>
</Button>
<Button fx:id="btn_movies" mnemonicParsing="false" prefHeight="48.0" prefWidth="172.0" text="Filme" wrapText="true" GridPane.columnSpan="3" GridPane.halignment="CENTER" GridPane.rowIndex="2" GridPane.valignment="CENTER">
<font>
<Font size="24.0" />
</font>
</Button>
<Button fx:id="btn_exit" mnemonicParsing="false" prefHeight="48.0" prefWidth="172.0" text="Beenden" GridPane.columnSpan="3" GridPane.halignment="CENTER" GridPane.rowIndex="6" GridPane.valignment="CENTER">
<font>
<Font size="24.0" />
</font>
</Button>
<Button fx:id="btn_settings" mnemonicParsing="false" prefHeight="48.0" prefWidth="172.0" text="Optionen" GridPane.columnSpan="3" GridPane.halignment="CENTER" GridPane.rowIndex="4" GridPane.valignment="CENTER">
<font>
<Font size="24.0" />
</font>
</Button>
<Button fx:id="btn_dashboard" mnemonicParsing="false" prefHeight="48.0" prefWidth="172.0" text="Dashboard" GridPane.columnSpan="3" GridPane.halignment="CENTER" GridPane.rowIndex="5" GridPane.valignment="CENTER">
<font>
<Font size="24.0" />
</font>
</Button>
</children>
</GridPane>
</left>
<top>
<AnchorPane fx:id="bp_top" prefHeight="200.0" prefWidth="200.0" BorderPane.alignment="CENTER">
<children>
<Label fx:id="headlabel" alignment="CENTER" layoutX="737.0" layoutY="92.0" prefHeight="200.0" prefWidth="1920.0" text="Dashboard" textAlignment="CENTER" AnchorPane.bottomAnchor="0.0" AnchorPane.leftAnchor="0.0" AnchorPane.rightAnchor="0.0" AnchorPane.topAnchor="0.0">
<font>
<Font size="48.0" />
</font>
</Label>
</children>
</AnchorPane>
</top>
<center>
<AnchorPane fx:id="bp_center" prefHeight="200.0" prefWidth="200.0" BorderPane.alignment="CENTER" />
</center>
<right>
<AnchorPane fx:id="bp_right" prefHeight="200.0" prefWidth="200.0" BorderPane.alignment="CENTER" />
</right>
</BorderPane>
</children>
</AnchorPane>
______________________________________________
package main.java.controllers;
import java.net.URL;
import java.util.ResourceBundle;
import javafx.fxml.FXML;
import javafx.scene.control.Button;
import javafx.scene.control.Label;
import javafx.scene.layout.AnchorPane;
import javafx.scene.layout.BorderPane;
import javafx.scene.layout.GridPane;
public class MainUIController{
@FXML // ResourceBundle that was given to the FXMLLoader
private ResourceBundle resources;
@FXML // URL location of the FXML file that was given to the FXMLLoader
private URL location;
@FXML // fx:id="btn_search"
private Button btn_search; // Value injected by FXMLLoader
@FXML // fx:id="btn_movies"
private Button btn_movies; // Value injected by FXMLLoader
@FXML // fx:id="btn_exit"
private Button btn_exit; // Value injected by FXMLLoader
@FXML // fx:id="btn_series"
private Button btn_series; // Value injected by FXMLLoader
@FXML // fx:id="bp_right"
private AnchorPane bp_right; // Value injected by FXMLLoader
@FXML // fx:id="bp_bottom"
private AnchorPane bp_bottom; // Value injected by FXMLLoader
@FXML // fx:id="borderPane01"
private BorderPane borderPane01; // Value injected by FXMLLoader
@FXML // fx:id="headlabel"
private Label headlabel; // Value injected by FXMLLoader
@FXML // fx:id="bp_left_grid"
private GridPane bp_left_grid; // Value injected by FXMLLoader
@FXML // fx:id="bp_top"
private AnchorPane bp_top; // Value injected by FXMLLoader
@FXML // fx:id="root"
private AnchorPane root; // Value injected by FXMLLoader
@FXML // fx:id="btn_download"
private Button btn_download; // Value injected by FXMLLoader
@FXML // fx:id="btn_dashboard
private Button btn_dashboard; // Value injected by FXMLLoader
@FXML // fx:id="bp_center"
private AnchorPane bp_center; // Value injected by FXMLLoader
@FXML // fx:id="btn_settings"
private Button btn_settings; // Value injected by FXMLLoader
@FXML // This method is called by the FXMLLoader when initialization is complete
void initialize() {
assert root != null : "fx:id=\"root\" was not injected: check your FXML file 'MainUI.fxml'.";
assert borderPane01 != null : "fx:id=\"borderPane01\" was not injected: check your FXML file 'MainUI.fxml'.";
assert bp_top != null : "fx:id=\"bp_top\" was not injected: check your FXML file 'MainUI.fxml'.";
assert headlabel != null : "fx:id=\"headlabel\" was not injected: check your FXML file 'MainUI.fxml'.";
assert bp_left_grid != null : "fx:id=\"bp_left_grid\" was not injected: check your FXML file 'MainUI.fxml'.";
assert bp_center != null : "fx:id=\"bp_center\" was not injected: check your FXML file 'MainUI.fxml'.";
assert bp_right != null : "fx:id=\"bp_right\" was not injected: check your FXML file 'MainUI.fxml'.";
assert bp_bottom != null : "fx:id=\"bp_bottom\" was not injected: check your FXML file 'MainUI.fxml'.";
assert btn_search != null : "fx:id=\"btn_search\" was not injected: check your FXML file 'MainUI.fxml'.";
assert btn_series != null : "fx:id=\"btn_series\" was not injected: check your FXML file 'MainUI.fxml'.";
assert btn_movies != null : "fx:id=\"btn_movies\" was not injected: check your FXML file 'MainUI.fxml'.";
assert btn_download != null : "fx:id=\"btn_download\" was not injected: check your FXML file 'MainUI.fxml'.";
assert btn_settings != null : "fx:id=\"btn_settings\" was not injected: check your FXML file 'MainUI.fxml'.";
assert btn_dashboard!= null : "fx:id=\"dashboard\" was not injected: check your FXML file 'MainUI.fxml'.";
assert btn_exit != null : "fx:id=\"btn_exit\" was not injected: check your FXML file 'MainUI.fxml'.";
btn_search.setOnAction(value -> {
System.out.println("Search pressed"); //TODO
});
btn_series.setOnAction(value ->{
System.out.println("series pressed");
});
btn_movies.setOnAction(value ->{
System.out.println("movies pressed");
});
btn_download.setOnAction(value ->{
System.out.println("download pressed");
});
btn_settings.setOnAction(value ->{
System.out.println("settings pressed");
});
btn_dashboard.setOnAction(value ->{
System.out.println("dashboard pressed");
});
btn_exit.setOnAction(value ->{
System.out.println("exit pressed");
});
}
}
Edit:Here is my package structure:
编辑:这是我的包结构:
src
|-application
|here is my main application
|-main
|-java
|-controllers
|here are my controllers
|-dao
|-service
|-ressources
|-css
|-images
|-view
|here are the fxml files
采纳答案by MalaKa
I suggest to change the project structure. The resources should not be resided in the sources itself. So my suggestion is the following project structure:
我建议改变项目结构。资源不应驻留在源本身中。所以我的建议是以下项目结构:
src
|-main
|-java <-- This should be your 'sources root'
|-application <-- The application itself is within the new sources root
|-controllers
|here are my controllers
|-dao
|-service
|-resources <-- all resources (css files, images, fxml files) should be with a subfolder of the resources. This folder should be marked as 'resources root'
|-css
|-images
|-view
|here are the fxml files
This structure can be set up in any IDE. How you can set it up depends on the IDE itself. Normally you can simply right-click the folder in the overview and mark is as sources/resources root. The exact names for 'source root' and 'resources root' depend on the IDE.
可以在任何 IDE 中设置此结构。如何设置取决于 IDE 本身。通常,您只需右键单击概览中的文件夹,然后将其标记为源/资源根目录。“源根”和“资源根”的确切名称取决于 IDE。
The Main
is now in the package application
and the MainUIController
is in the package controllers
.
在Main
现在是在包装application
和MainUIController
在包controllers
。
In the FXML-File you should specify:
在 FXML 文件中,您应该指定:
fx:controller="controllers.MainUIController"
Loading the FXML-File should work with:
加载 FXML 文件应该适用于:
AnchorPane root = (AnchorPane) FXMLLoader.load(getClass().getClassLoader().getResource("view/MainUI.fxml"));
As a reference for the following explanation, have a look here:
The ClassLoader
always starts at the root of your resources. If you only use getClass
, the path to the resource is a relative path. After dealing with it several times, I for myself have decided to always use absolute paths and therefore use the getClassLoader
.
As explained in the link above, please note that
至于下面的解释参考,看看这里:
将ClassLoader
始终从你的资源的根本。如果只使用getClass
,则资源的路径是相对路径。经过多次处理后,我自己决定始终使用绝对路径,因此使用getClassLoader
.
如上面链接中所述,请注意
getClass().getClassLoader().getResource("view/MainUI.fxml");
could be replaced by
可以替换为
getClass().getResource("view/MainUI.fxml");
I think that I somewhere read, that it is better to directly use the InputStream
if available, as dealing with URLs within JAR-Files can be tricky sometimes (but I currently can't find a reference to support that). So as an alternative to the getResource(..)
, you could use:
我认为我在某处读过,最好直接使用InputStream
if available,因为处理 JAR 文件中的 URL 有时会很棘手(但我目前找不到支持它的参考)。因此,作为 的替代方案getResource(..)
,您可以使用:
FXMLLoader loader = new FXMLLoader();
Parent root = loader.load(getClass().getClassLoader().getResourceAsStream("view/MainUI.fxml");
回答by James_D
The fx:controller
attribute is expecting the fully qualified classname of the controller class. I.e. assuming you have
该fx:controller
属性需要控制器类的完全限定类名。即假设你有
package main.java.controllers ;
public class MainUIController { ... }
you should have
你应该有
fx:controller="main.java.controllers.MainUIController"