anchor.diff:      };
   
       public void setProgress(final float progress, final String loadingText) {
  -        //since this method is called from another thread, we enqueue the changes to the progressbar to the update loop thread
  -        enqueue(new Callable() {
  -
  -            public Object call() throws Exception {
  -                final int MIN_WIDTH = 32;
  -                int pixelWidth = (int) (MIN_WIDTH + (progressBarElement.getParent().getWidth() - MIN_WIDTH) * progress);
  -                progressBarElement.setConstraintWidth(new SizeValue(pixelWidth + "px"));
  -                progressBarElement.getParent().layoutElements();
  -
  -                textRenderer.setText(loadingText);
  -                return null;
  -            }
  +        //Since this method is called from another thread, we enqueue the
  +        //changes to the progressbar to the update loop thread.
  +        enqueue(() -> {
  +            final int MIN_WIDTH = 32;
  +            int pixelWidth = (int) (MIN_WIDTH + (progressBarElement.getParent().
  +                    getWidth() - MIN_WIDTH) * progress);
  +            progressBarElement.setConstraintWidth(new SizeValue(pixelWidth
  +                    + "px"));
  +            progressBarElement.getParent().layoutElements();
  +
  +            textRenderer.setText(loadingText);
  +            return null;
           });
   
       }
  
positive.code:     public void simpleUpdate(float tpf) {
          if (load) {
              if (loadFuture == null) {
                  //if we have not started loading yet, submit the Callable to the executor
                  loadFuture = exec.submit(loadingCallable);
              }
              //check if the execution on the other thread is done
  
negative.code: 
      @Override
      public void bind(Nifty nifty, Screen screen) {
          progressBarElement = nifty.getScreen("loadlevel").findElementById(
                  "progressbar");
      }
  
      // methods for Controller
  