import java.util.concurrent.Executors;
import java.util.concurrent.TimeUnit;
import java.util.stream.IntStream;

import javafx.application.Application;
import javafx.application.Platform;
import javafx.scene.Scene;
import javafx.scene.control.CheckBox;
import javafx.scene.control.ScrollPane;
import javafx.scene.control.ScrollPane.ScrollBarPolicy;
import javafx.scene.control.SplitPane;
import javafx.scene.layout.Region;
import javafx.scene.layout.VBox;
import javafx.stage.Stage;

public class Test extends Application {

	@Override
	public void start(Stage stage) {
		final var contentVBox = new VBox(8);
		contentVBox.widthProperty().addListener((o, a, b) -> System.out.println("new vBox width: " + b));
		contentVBox.getChildren().addAll(IntStream.rangeClosed(1, 6).mapToObj(i -> new CheckBox("Item " + i)).toList());

		final var scrollPane = new ScrollPane(contentVBox);
		scrollPane.setFitToWidth(false);
		scrollPane.setStyle("-fx-background: white;");
		scrollPane.setHbarPolicy(ScrollBarPolicy.NEVER);
		scrollPane.minWidthProperty().bind(contentVBox.widthProperty());
		scrollPane.maxWidthProperty().bind(contentVBox.widthProperty());

		final var splitPane = new SplitPane(new Region(), scrollPane);
		splitPane.setStyle("-fx-background-color: gainsboro;");

		final var scene = new Scene(splitPane, 800, 500);
		stage.setScene(scene);
		stage.show();

		final var scheduledExecutor = Executors.newSingleThreadScheduledExecutor();
		scheduledExecutor.schedule(() -> {
			Platform.runLater(() -> {
				contentVBox.getChildren().add(new CheckBox("CheckBoxWithLongItemName"));

// doesn't change anything
				splitPane.requestLayout();
				splitPane.layout();
			});

			scheduledExecutor.shutdown();
		}, 5, TimeUnit.SECONDS);
	}

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