How to style the separator using CSS in JavaFX?

A separator is a horizontal or, the vertical line separating the UI elements of an application. In JavaFX the javafx.scene.control.Separator class represents a separator, to create a separator you need to instantiate this class. You can control the visual appearance of the separator using CSS.

You create an alternative style to the separator, by creating a CSS file and enabling it in your application. Once you do so, the created style will be applied to all the separators in the application.

The setStyle() method accepts the CSS in string format and applies the specified style to the separator. Using this method you can enhance the visualization of the separator as shown below −

//Setting style for the separator using CSS
sep.setStyle("-fx-border-color:#D2691E; -fx-border-width:2");

Example

import javafx.application.Application;
import javafx.geometry.HPos;
import javafx.geometry.Insets;
import javafx.geometry.Orientation;
import javafx.scene.Scene;
import javafx.scene.control.CheckBox;
import javafx.scene.control.Label;
import javafx.scene.control.Separator;
import javafx.scene.layout.HBox;
import javafx.scene.layout.VBox;
import javafx.scene.paint.Color;
import javafx.scene.text.Font;
import javafx.scene.text.FontPosture;
import javafx.scene.text.FontWeight;
import javafx.stage.Stage;
public class StylingSeparator extends Application {
   public void start(Stage stage) {
      //Creating the check boxes
      CheckBox checkBox1 = new CheckBox("Java");
      CheckBox checkBox2 = new CheckBox("Python");
      CheckBox checkBox3 = new CheckBox("C++");
      CheckBox checkBox4 = new CheckBox("MongoDB");
      CheckBox checkBox5 = new CheckBox("Neo4J");
      CheckBox checkBox6= new CheckBox("Casandra");
      //Creating the label
      Label label = new Label("Select Technologies:");
      Font font = Font.font("verdana", FontWeight.BOLD, FontPosture.REGULAR, 12);
      label.setFont(font);
      //Creating a separator
      Separator sep = new Separator();
      sep.setOrientation(Orientation.VERTICAL);
      sep.setMaxHeight(75);
      sep.setHalignment(HPos.CENTER);
      //Setting style for the separator using CSS
      sep.setStyle("-fx-border-color:#D2691E; -fx-border-width: 2;");
      //Adding the check boxes and separator to the pane
      VBox box1 = new VBox(5);
      box1.setPadding(new Insets(5, 5, 5, 50));
      box1.getChildren().addAll(checkBox1, checkBox2, checkBox3);
      VBox box2 = new VBox(5);
      box2.setPadding(new Insets(5, 5, 5, 10));
      box2.getChildren().addAll(checkBox4, checkBox5, checkBox6);
      HBox root = new HBox(box1, box2);
      root.getChildren().add(1,sep);
      //Setting the stage
      Scene scene = new Scene(root, 595, 130, Color.BEIGE);
      stage.setTitle("Separator Example");
      stage.setScene(scene);
      stage.show();
   }
      public static void main(String args[]){
      launch(args);
   }
}

Output