title: IntelliJ Idea + JavaFX = class.getResource() returns null
body: <p>I know, there are lots of similar question around here with similar problems, but after reading tons of posts, I cannot simply solve this issue.
  Under <strong>Compiler > Resource Patterns</strong>, I've already put this string "*.fxml". Moreover, I've marked the resources folder as the Resources Root.  </p>
  
  <p>Here you can see my project structure:</p>
  
  <p><a href="https://i.stack.imgur.com/K9Z2l.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/K9Z2l.png" alt="Project Structure"></a></p>
  
  <p>This is my <strong>MainView.java</strong> class. </p>
  
  <pre><code>package dataParser.View;
  
  import javafx.application.Application;
  import javafx.fxml.FXMLLoader;
  import javafx.scene.Parent;
  import javafx.scene.Scene;
  import javafx.stage.Stage;
  
  
  public class MainView extends Application {
      private Stage primaryStage;
  
      public static void main(String[] args) {
          launch(args);
      }
  
      @Override
      public void start(Stage primaryStage) throws Exception {
          this.primaryStage = primaryStage;
  
          FXMLLoader loader = new FXMLLoader();
          System.out.println(this.getClass().getResource("/MainView.fxml"));
          loader.setLocation(getClass().getResource("/MainView.fxml"));
  
          MainViewController mainViewController = new MainViewController();
          mainViewController.setMainApp(this);
  
          loader.setController(mainViewController);
          Parent layout = loader.load();
  
          Scene scene = new Scene(layout);
          primaryStage.setScene(scene);
          primaryStage.show();
      }
  
      Stage getPrimaryStage() {
          return primaryStage;
      }
  
  }
  </code></pre>
  
  <p>Still, I'm just getting back a null resource. Any hints?<br>
  Thank you!</p>
  
  <p><strong>EDIT</strong><br>
  This is the complete stack-trace. I've also noticed that I've issues linking all my resource files.</p>
  
  <pre><code>    Exception in thread "main" java.lang.RuntimeException: Exception in Application start method
      at javafx.graphics/com.sun.javafx.application.LauncherImpl.launchApplication1(LauncherImpl.java:973)
      at javafx.graphics/com.sun.javafx.application.LauncherImpl.lambda$launchApplication$2(LauncherImpl.java:198)
      at java.base/java.lang.Thread.run(Thread.java:844)
  Caused by: java.lang.IllegalStateException: Location is not set.
      at javafx.fxml/javafx.fxml.FXMLLoader.loadImpl(FXMLLoader.java:2459)
      at javafx.fxml/javafx.fxml.FXMLLoader.load(FXMLLoader.java:2435)
      at dataParser.View.MainView.start(MainView.java:29)
      at javafx.graphics/com.sun.javafx.application.LauncherImpl.lambda$launchApplication1$9(LauncherImpl.java:919)
      at javafx.graphics/com.sun.javafx.application.PlatformImpl.lambda$runAndWait$11(PlatformImpl.java:449)
      at javafx.graphics/com.sun.javafx.application.PlatformImpl.lambda$runLater$9(PlatformImpl.java:418)
      at java.base/java.security.AccessController.doPrivileged(Native Method)
      at javafx.graphics/com.sun.javafx.application.PlatformImpl.lambda$runLater$10(PlatformImpl.java:417)
      at javafx.graphics/com.sun.glass.ui.InvokeLaterDispatcher$Future.run(InvokeLaterDispatcher.java:96)
      at javafx.graphics/com.sun.glass.ui.win.WinApplication._runLoop(Native Method)
      at javafx.graphics/com.sun.glass.ui.win.WinApplication.lambda$runLoop$3(WinApplication.java:175)
      ... 1 more
  </code></pre>