How to install javafx to Eclipse - eclipse

Question

First of all, i am a newbie to Eclipse and Java.
So, my problem is, that i am unable to install javafx to my Eclipse.
What i have installed:
https://www.oracle.com/java/technologies/javase-jdk13-downloads.html (Windows x64 installer)
https://www.java.com/de/download/win10.jsp (download button)
What i already tried:
i followed this guide on how to install Maven and then javafx:
https://www.vogella.com/tutorials/EclipseMaven/article.html
For the POM.xml file i used the code from this link:
https://search.maven.org/remotecontent?filepath=org/openjfx/javafx/15-ea+1/javafx-15-ea+1.pom
Now, after creating a new Maven project and trying to import (e.g. javafx.scene.shape.Rectangle) i get this error:
(After importing jfxrt.jar)
Error: JavaFX runtime components are missing, and are required to run this application
An Example Code i want to run is from my friend:
package vierGewinnt;
import javafx.application.Application;
import javafx.event.EventHandler;
import javafx.scene.Scene;
import javafx.scene.control.Button;
import javafx.scene.input.KeyEvent;
import javafx.scene.layout.VBox;
import javafx.stage.Stage;
public class Game extends Application{
public static void main(String[] args){
launch(args);
}
public void start(Stage primaryStage){
Field field = new Field();
Button newGame = new Button("Neues Spiel");
PositionColumn pos = new PositionColumn();
VBox root = new VBox();
root.getChildren().addAll(field, pos, newGame);
Scene scene = new Scene(root);
scene.addEventHandler(KeyEvent.KEY_RELEASED, new EventHandler<KeyEvent>(){
#Override
public void handle(KeyEvent event) {
/*if(field.victory()){
Stage secondaryStage = new Stage();
HBox viBox = new HBox();
Scene viScene = new Scene(viBox);
secondaryStage.setScene(viScene);
secondaryStage.show();
}*/
if (event instanceof KeyEvent)
field.setStone(event);
}
});
primaryStage.setScene(scene);
primaryStage.show();
}
}
(There are other classes for this to work, thats not the problem)
So, at this point i dont know what to next to make it work, or how to get javafx to work in a different way

Answer 1

You are using a JDK version 13 which no longer includes JavaFX. So you need to add JavaFX manually to your project.
This is quite easy, because you are using a Maven project. So all you need to do is:
open the pom.xml file of your project (in the top level directory of your project)
add the javafx dependency to your maven dependencies
(maybe) refresh your maven project (Alt + F5) for eclipse to notice the changes
To add the maven dependency to your project you simply add this to the pom.xml file (somewhere between the tags <dependencies> and </dependencies>:
<dependency>
<groupId>org.openjfx</groupId>
<artifactId>javafx</artifactId>
<version>11</version>
<type>pom</type>
</dependency>
Edit:
To answer your second question about the exception that occures when starting the application:
The StackTrace says:
Caused by: java.lang.IllegalAccessException: class
com.sun.javafx.application.LauncherImpl (in module javafx.graphics)
cannot access class vierGewinnt.Game (in module
org.openjfx.archetype_simple) because module
org.openjfx.archetype_simple does not export vierGewinnt to module
javafx.graphics
So the problem is that the class vierGewinnt.Game can't be created because it can't be accessed. That's because it is not exported. If you add the export it should work.