To reproduce run the app below:

import javafx.application.Application;
import javafx.event.ActionEvent;
import javafx.event.EventHandler;
import javafx.scene.Scene;
import javafx.scene.control.Button;
import javafx.scene.control.ButtonBuilder;
import javafx.scene.control.ScrollPane;
import javafx.scene.control.TextArea;
import javafx.scene.control.TextAreaBuilder;
import javafx.scene.control.TextField;
import javafx.scene.control.TextFieldBuilder;
import javafx.scene.layout.VBox;
import javafx.stage.Stage;

public class ScrollPaneTestDrive extends Application {

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

    @Override
    public void start(Stage stage) throws Exception {

        VBox topContainer = new VBox();
        topContainer.setMaxWidth(100d);
        topContainer.setMaxHeight(100d);
        topContainer.setStyle("-fx-border-color: blue;");
        
        Button button = ButtonBuilder.create().text("Press me").build();
        final TextField tf1 = TextFieldBuilder.create().text("0").build();
        button.setOnAction(new EventHandler<ActionEvent>() {
            @Override
            public void handle(ActionEvent t) {
                tf1.setText(String.valueOf(Integer.parseInt(tf1.getText()) + 1));
            }
        });

        TextArea tf2 = TextAreaBuilder.create().prefHeight(100).build();
        for (int i = 0; i < 15; i++) {
            tf2.appendText("text" + i + "\n");
        }
        Button empty = ButtonBuilder.create().text("This is empty-action button").build();

        topContainer.getChildren().addAll(button, tf1, tf2, empty);

        ScrollPane scrollPane = new ScrollPane();
        
        scrollPane.setContent(topContainer);

        Scene scene = new Scene(scrollPane, 300, 200);
        stage.setScene(scene);
        stage.setTitle(System.getProperty("java.runtime.version") + "; " + System.getProperty("javafx.runtime.version"));
        stage.show();
    }
}