code: @PostConstruct
      public void init() {
  
          for (int i = 0; i < 100; i++) {
              contentList.getItems().add("Item " + i);
          }
          contentList.setMaxHeight(3400);
  
          JFXScrollPane.smoothScrolling((ScrollPane) scroll.getChildren().get(0));
  
          SVGGlyph arrow = new SVGGlyph(0,
              "FULLSCREEN",
              "M402.746 877.254l-320-320c-24.994-24.992-24.994-65.516 0-90.51l320-320c24.994-24.992 65.516-24.992 90.51 0 24.994 24.994 "
              + "24.994 65.516 0 90.51l-210.746 210.746h613.49c35.346 0 64 28.654 64 64s-28.654 64-64 64h-613.49l210.746 210.746c12.496 "
              + "12.496 18.744 28.876 18.744 45.254s-6.248 32.758-18.744 45.254c-24.994 24.994-65.516 24.994-90.51 0z",
              Color.WHITE);
          arrow.setSize(20, 16);
          backButton.setGraphic(arrow);
          backButton.setRipplerFill(Color.WHITE);
      }
docs: init fxml when loaded.