As its name suggests, scaling refers to increasing or decreasing the size of an object. In computer graphics, by applying the scale transition on an object (or image), you can either increase or decrease its size, for a specified duration.

This transition can also be applied on various JavaFX nodes, on 2D shapes, 3D shapes, text, and any other element on an application.

Scale Transition in JavaFX

The Scale transition is performed in JavaFX using the ScaleTransition class which belongs to the javafx.animation package. This class contains various properties that assist in playing this animation on a JavaFX application −

• byX − Specifies the incremented stop X scale value, from the start, of this ScaleTransition.

• byY − Specifies the incremented stop Y scale value, from the start, of this ScaleTransition.

• byZ − Specifies the incremented stop Z scale value, from the start, of this ScaleTransition.

• duration − The duration of this ScaleTransition

• fromX − Specifies the start X scale value of this ScaleTransition.

• fromY − Specifies the start Y scale value of this ScaleTransition.

• fromZ − Specifies the start Z scale value of this ScaleTransition.

• node − The target node of this ScaleTransition.

• toX − Specifies the stop X scale value of this ScaleTransition.

• toY − The stop Y scale value of this ScaleTransition.

• toZ − The stop Z scale value of this ScaleTransition.

Example

Following is the program which demonstrates Scale Transition in JavaFX. Save this code in a file with the name ScaleTransitionExample.java.

import javafx.animation.ScaleTransition; 
import javafx.application.Application; 
import static javafx.application.Application.launch; 
import javafx.scene.Group; 
import javafx.scene.Scene; 
import javafx.scene.paint.Color; 
import javafx.scene.shape.Circle; 
import javafx.stage.Stage; 
import javafx.util.Duration; 
         
public class ScaleTransitionExample extends Application {  
   @Override 
   public void start(Stage stage) {      
      //Drawing a Circle 
      Circle circle = new Circle(); 
      
      //Setting the position of the circle 
      circle.setCenterX(300.0f); 
      circle.setCenterY(135.0f); 
      
      //Setting the radius of the circle 
      circle.setRadius(50.0f); 
      
      //Setting the color of the circle 
      circle.setFill(Color.BROWN); 
      
      //Setting the stroke width of the circle 
      circle.setStrokeWidth(20); 
       
      //Creating scale Transition 
      ScaleTransition scaleTransition = new ScaleTransition(); 
      
      //Setting the duration for the transition 
      scaleTransition.setDuration(Duration.millis(1000)); 
      
      //Setting the node for the transition 
      scaleTransition.setNode(circle); 
      
      //Setting the dimensions for scaling 
      scaleTransition.setByY(1.5); 
      scaleTransition.setByX(1.5); 
      
      //Setting the cycle count for the translation 
      scaleTransition.setCycleCount(50); 
      
      //Setting auto reverse value to true 
      scaleTransition.setAutoReverse(false); 
      
      //Playing the animation 
      scaleTransition.play(); 
         
      //Creating a Group object  
      Group root = new Group(circle); 
         
      //Creating a scene object  
      Scene scene = new Scene(root, 600, 300); 
      
      //Setting title to the Stage 
      stage.setTitle("Scale transition example"); 
         
      //Adding scene to the stage 
      stage.setScene(scene); 
         
      //Displaying the contents of the stage 
      stage.show(); 
   }      
   public static void main(String args[]){ 
      launch(args); 
   } 
}

Compile and execute the saved java file from the command prompt using the following commands.

javac --module-path %PATH_TO_FX% --add-modules javafx.controls ScaleTransitionExample.java 
java --module-path %PATH_TO_FX% --add-modules javafx.controls ScaleTransitionExample

Output

On executing, the above program generates a JavaFX window as shown below.