To reproduce run following code and scroll mouse wheel on vertical scrollbar



import javafx.application.Application;
import javafx.scene.Parent;
import javafx.scene.Scene;
import javafx.scene.control.ScrollPane;

import javafx.scene.layout.HBox;
import javafx.scene.layout.VBox;
import javafx.scene.shape.Rectangle;
import javafx.stage.Stage;

public class ScrollPaneSampleRectangle extends Application {

    public static void main(String[] args) {
        launch( args);
    }

   private Parent getContent() {
        VBox box = new VBox();
        ScrollPane pane = new ScrollPane();
        HBox hbox = new HBox(20);
        hbox.getChildren().add(new Rectangle(10,10));
        pane.setContent(hbox);
        pane.setStyle("-fx-vbar-policy: always;");
        pane.setFocusTraversable(false);
        pane.setMaxSize(100, 100);
        box.getChildren().add(pane);


        return box;
    }

    public void start(Stage stage) {
        stage.setX(100);
        stage.setY(100);
        stage.setWidth(300);
        stage.setHeight(300);
        Scene scene = new Scene(getContent());
        stage.setScene(scene);
        stage.show();
    }
}