JavaFX | Background Class

Background class is a part of JavaFX. Background class sets the background of a region. Every background is composed of several fills or background images but cannot be null but it may be empty. Background class is immutable, so you can freely reuse the same Background on many different Regions.

Constructors of the class:

1. Background(BackgroundFill… f): Creates a new background object with specified fills.
2. Background(BackgroundFill[] fills, BackgroundImage[] images): Creates a new background object with specified fills and background image.
3. Background(BackgroundImage… i): Creates a new background object with specified background images.
4. Background(List fills, List images): Creates a new background object with list of specified fills and background images.

Commonly Used Methods:

Below programs illustrate the use of Background class:

1. Java program to set a fill for the background of a container: In this program we will create a Background named background with specified BackgroundFill and add this to the background. We will create an HBox named hbox, a Label named label, TextField named textfield and a Button named button . Now add the label, textfield and button to the HBox. We will set the background of hbox using the setBackground() function.Now set the alignment of HBox to Pos.CENTER and also add some spacing between the nodes using setSpacing() method. We will create a Scene named scene and add the HBox to the scene. The scene will be set to the stage using the setScene() function. We will call the show() function to display the results.

   
   

   
   
   

   // Java program to set a fill for the background  // of a container import javafx.application.Application; import javafx.scene.Scene; import javafx.scene.control.*; import javafx.scene.layout.*; import javafx.stage.Stage; import javafx.event.ActionEvent; import javafx.event.EventHandler; import javafx.scene.canvas.*; import javafx.scene.web.*; import javafx.scene.layout.*; import javafx.scene.image.*; import java.io.*; import javafx.geometry.*; import javafx.scene.Group; import javafx.scene.paint.*;    public class Background_2 extends Application {        // launch the application     public void start(Stage stage)     {            try {                // set title for the stage             stage.setTitle("creating Background");                // create a label             Label label = new Label("Name : ");                // create a text field             TextField textfield = new TextField();                // set preferred column count             textfield.setPrefColumnCount(10);                // create a button             Button button = new Button("OK");                // add the label, text field and button             HBox hbox = new HBox(label, textfield, button);                // set spacing             hbox.setSpacing(10);                // set alignment for the HBox             hbox.setAlignment(Pos.CENTER);                // create a scene             Scene scene = new Scene(hbox, 280, 280);                // create a background fill             BackgroundFill background_fill = new BackgroundFill(Color.PINK,                                            CornerRadii.EMPTY, Insets.EMPTY);                // create Background             Background background = new Background(background_fill);                // set background             hbox.setBackground(background);                // set the scene             stage.setScene(scene);                stage.show();         }            catch (Exception e) {                System.out.println(e.getMessage());         }     }        // Main Method     public static void main(String args[])     {            // launch the application         launch(args);     } }

   Output:

   

2. Java program to add an image to the background of a container: In this program we will create a Background named background with specified BackgroundImage and add this image to the background of the container. Import the image using the FileInputStream and then convert the file into Image object Use this Image object to create a BackgroundImage. We will create an HBox named hbox, a Label named label, TextField named textfield and a Button named button . Now add the label, textfield, and button to the HBox. Set the background of the hbox using the setBackground() function. Set the alignment of HBox to Pos.CENTER and also add some spacing between the nodes using setSpacing() method. We will create a Scene named scene and add the HBox to the scene. The scene will be set to the stage using the setScene() function. Finally call the show() method to display the result.

   
   

   
   
   

   // Java program to add an image to  // the background of a container import javafx.application.Application; import javafx.scene.Scene; import javafx.scene.control.*; import javafx.scene.layout.*; import javafx.stage.Stage; import javafx.event.ActionEvent; import javafx.event.EventHandler; import javafx.scene.canvas.*; import javafx.scene.web.*; import javafx.scene.layout.*; import javafx.scene.image.*; import java.io.*; import javafx.geometry.*; import javafx.scene.Group;    public class Background_1 extends Application {        // launch the application     public void start(Stage stage)     {            try {                // set title for the stage             stage.setTitle("creating Background");                // create a label             Label label = new Label("Name : ");                // create a text field             TextField textfield = new TextField();                // set preferred column count             textfield.setPrefColumnCount(10);                // create a button             Button button = new Button("OK");                // add the label, text field and button             HBox hbox = new HBox(label, textfield, button);                // set spacing             hbox.setSpacing(10);                // set alignment for the HBox             hbox.setAlignment(Pos.CENTER);                // create a scene             Scene scene = new Scene(hbox, 280, 280);                // create a input stream             FileInputStream input = new FileInputStream("f:\\gfg.png");                // create a image             Image image = new Image(input);                // create a background image             BackgroundImage backgroundimage = new BackgroundImage(image,                                               BackgroundRepeat.NO_REPEAT,                                               BackgroundRepeat.NO_REPEAT,                                               BackgroundPosition.DEFAULT,                                                  BackgroundSize.DEFAULT);                // create Background             Background background = new Background(backgroundimage);                // set background             hbox.setBackground(background);                // set the scene             stage.setScene(scene);                stage.show();         }            catch (Exception e) {                System.out.println(e.getMessage());         }     }        // Main Method     public static void main(String args[])     {            // launch the application         launch(args);     } }

   Output:
   

Note: The above programs might not run in an online IDE. Please use an offline compiler.

Reference: https://docs.oracle.com/javase/8/javafx/api/javafx/scene/layout/Background.html