JavaFX - 动画

简述

通常，动画对象意味着通过快速显示来创建其运动的错觉。在 JavaFX 中，可以通过随时间更改其属性来对节点进行动画处理。JavaFX 提供了一个名为的包javafx.animation. 此包包含用于为节点设置动画的类。动画是所有这些类的基类。

使用 JavaFX，您可以应用动画（过渡），例如 Fade Transition, Fill Transition, Rotate Transition, Scale Transition, Stroke Transition, Translate Transition, Path Transition, Sequential Transition, Pause Transition, Parallel Transition，等等。

所有这些转换都由包中的各个类表示 javafx.animation.

要将特定动画应用于节点，您必须按照以下步骤操作 -

使用相应的类创建一个 require 节点。
实例化要应用的相应过渡（动画）类
设置过渡的属性和
最后使用 play() 的方法 Animation 班级。

在本章中，我们将讨论基本转换（旋转、缩放、平移）的示例。

旋转过渡

以下是在 JavaFX 中演示 Rotate Transition 的程序。将此代码保存在名称为的文件中RotateTransitionExample.java.


import javafx.animation.RotateTransition; 
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.Polygon; 
import javafx.stage.Stage; 
import javafx.util.Duration; 
         
public class RotateTransitionExample extends Application { 
   @Override 
   public void start(Stage stage) {      
      //Creating a hexagon 
      Polygon hexagon = new Polygon();        
      
      //Adding coordinates to the hexagon 
      hexagon.getPoints().addAll(new Double[]{        
         200.0, 50.0, 
         400.0, 50.0, 
         450.0, 150.0,          
         400.0, 250.0, 
         200.0, 250.0,                   
         150.0, 150.0, 
      }); 
      //Setting the fill color for the hexagon 
      hexagon.setFill(Color.BLUE); 
       
      //Creating a rotate transition    
      RotateTransition rotateTransition = new RotateTransition(); 
      
      //Setting the duration for the transition 
      rotateTransition.setDuration(Duration.millis(1000)); 
      
      //Setting the node for the transition 
      rotateTransition.setNode(hexagon);       
      
      //Setting the angle of the rotation 
      rotateTransition.setByAngle(360); 
      
      //Setting the cycle count for the transition 
      rotateTransition.setCycleCount(50); 
      
      //Setting auto reverse value to false 
      rotateTransition.setAutoReverse(false); 
      
      //Playing the animation 
      rotateTransition.play(); 
         
      //Creating a Group object   
      Group root = new Group(hexagon); 
         
      //Creating a scene object 
      Scene scene = new Scene(root, 600, 300);   
      
      //Setting title to the Stage 
      stage.setTitle("Rotate 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); 
   } 
}

使用以下命令从命令提示符编译并执行保存的 java 文件。


javac RotateTransitionExample.java 
java RotateTransitionExample

执行时，上述程序会生成一个 JavaFX 窗口，如下所示。

尺度过渡

以下是在 JavaFX 中演示 Scale Transition 的程序。将此代码保存在名称为的文件中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); 
   } 
}

使用以下命令从命令提示符编译并执行保存的 java 文件。


javac ScaleTransitionExample.java 
java ScaleTransitionExample

执行时，上述程序会生成一个 JavaFX 窗口，如下所示。

转换过渡

以下是在 JavaFX 中演示 Translate Transition 的程序。将此代码保存在名称为的文件中TranslateTransitionExample.java.


import javafx.animation.TranslateTransition; 
import javafx.application.Application; 
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 TranslateTransitionExample extends Application { 
   @Override 
   public void start(Stage stage) {  
      //Drawing a Circle 
      Circle circle = new Circle(); 
      
      //Setting the position of the circle 
      circle.setCenterX(150.0f); 
      circle.setCenterY(135.0f); 
      
      //Setting the radius of the circle 
      circle.setRadius(100.0f); 
      
      //Setting the color of the circle 
      circle.setFill(Color.BROWN); 
      
      //Setting the stroke width of the circle 
      circle.setStrokeWidth(20); 
       
      //Creating Translate Transition 
      TranslateTransition translateTransition = new TranslateTransition(); 
      
      //Setting the duration of the transition  
      translateTransition.setDuration(Duration.millis(1000)); 
      
      //Setting the node for the transition 
      translateTransition.setNode(circle); 
      
      //Setting the value of the transition along the x axis. 
      translateTransition.setByX(300); 
      
      //Setting the cycle count for the transition 
      translateTransition.setCycleCount(50); 
      
      //Setting auto reverse value to false 
      translateTransition.setAutoReverse(false); 
      
      //Playing the animation 
      translateTransition.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("Translate 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); 
   } 
}

使用以下命令从命令提示符编译并执行保存的 java 文件。


javac TranslateTransitionExample.java 
java TranslateTransitionExample

执行时，上述程序会生成一个 JavaFX 窗口，如下所示。

除此之外，JavaFX 还提供了在节点上应用更多转换的类。以下是 JavaFX 支持的其他类型的转换。

影响节点属性的过渡Fade、Fill、Stroke
涉及多个基本转换的转换顺序、并行、暂停
Transition 沿指定路径平移对象Path Transition