import javafx.application.Application;
import javafx.scene.Scene;
import javafx.scene.control.ListView;
import javafx.scene.paint.Color;
import javafx.scene.shape.Rectangle;
import javafx.stage.Stage;

public class Bug extends Application {
    @Override
    public void start(Stage primaryStage) {
        
        ListView listView = new ListView();
        for (int i = 0; i < 4; i++) {
            listView.getItems().add(new Rectangle(100, 200, Color.RED));
            listView.getItems().add(new Rectangle(100, 10, Color.BLUE));
        }

        Scene scene = new Scene(listView, 300, 300);

        primaryStage.setScene(scene);
        primaryStage.show();
    }


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