import java.util.Arrays;
import javafx.application.Application;
import javafx.geometry.Insets;
import javafx.scene.Node;
import javafx.scene.Scene;
import javafx.scene.control.ComboBox;
import javafx.scene.image.Image;
import javafx.scene.layout.Border;
import javafx.scene.layout.BorderImage;
import javafx.scene.layout.BorderRepeat;
import javafx.scene.layout.BorderWidths;
import javafx.scene.layout.Pane;
import javafx.scene.layout.Region;
import javafx.stage.Stage;

public class ComboBoxBackground extends Application {

    Pane pane;
    Node control;

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

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

        pane = new Pane();
        control = new ComboBox() {
            {
                getItems().addAll(Arrays.asList("one", "two", "three"));
                getSelectionModel().select(0);
                setFocusTraversable(false);
            }
        };
        pane.getChildren().add(control);

        control.setStyle(control.getStyle() + "-fx-background-image: "
                + "url(\"red-rectangle.png\");");

        Scene scene = new Scene(pane, 500, 500);
        stage.setScene(scene);
        stage.show();
    }
}