JavaFX | Background Class

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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:

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

Commonly Used Methods:

Method	Explanation
getFills()	Returns the list of all the fills of a background.
getImages()	Returns the list of all the background images of a background.
getOutsets()	Returns outsets of this Background.
isEmpty()	Returns whether the background is empty.
isFillPercentageBased()	Returns whether the fill of this Background is based on percentages.

Below programs illustrate the use of Background class:

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:

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);
    }
}