Javafx 简明教程

JavaFX - Stroke Transition

我们已了解到填充过渡用于改变形状区域的颜色。与之类似，描边过渡用于改变形状的描边颜色。

We have learned that the fill transition is used to change the colors of a shape area. Similar to it, the stroke transition is used to change the stroke color of a shape.

JavaFX 中的形状可以包含三种类型的描边：内部、外部和居中；并且对其应用不同的属性。此过渡忽视描边的属性，而只是在指定的持续时间内改变其颜色。

A shape in JavaFX can consist of three types of strokes: inside, outside and centered; with different properties applied to it. This transition is ignorant to the property of a stroke and instead just changes its color over a course of duration specified.

Stroke Transition

JavaFX 使用属于 javafx.animation 包的 StrokeTransition 类提供描边过渡。通过导入此类，我们可以在 JavaFX 应用程序中更改任何形状的描边颜色。要实现此动画，此类提供了多种属性：

JavaFX offers stroke transition using the StrokeTransition class which belongs to the javafx.animation package. By importing this class, we can change the stroke color of any shape on a JavaFX application. To implement this animation, there are various properties this class provides −

  1. duration − The duration of this StrokeTransition.

  2. shape − The target shape of this StrokeTransition.

  3. fromValue − Specifies the start color value for this StrokeTransition.

  4. toValue − Specifies the stop color value for this StrokeTransition.

Example

以下是演示 JavaFX 中 Stoke 过渡的程序。将此代码保存在名为 StrokeTransitionExample.java 的文件中。

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

import javafx.animation.StrokeTransition;
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 StrokeTransitionExample 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(100.0f);

      //Setting the color of the circle
      circle.setFill(Color.BROWN);

      //Setting the stroke width of the circle
      circle.setStrokeWidth(20);

      //creating stroke transition
      StrokeTransition strokeTransition = new StrokeTransition();

      //Setting the duration of the transition
      strokeTransition.setDuration(Duration.millis(1000));

      //Setting the shape for the transition
      strokeTransition.setShape(circle);

      //Setting the fromValue property of the transition (color)
      strokeTransition.setFromValue(Color.BLACK);

      //Setting the toValue property of the transition (color)
      strokeTransition.setToValue(Color.BROWN);

      //Setting the cycle count for the transition
      strokeTransition.setCycleCount(50);

      //Setting auto reverse value to false
      strokeTransition.setAutoReverse(false);

      //Playing the animation
      strokeTransition.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("Stroke 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已保存的 java 文件。

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 StrokeTransitionExample.java
java --module-path %PATH_TO_FX% --add-modules javafx.controls StrokeTransitionExample

执行后，上述程序会生成如下所示的 JavaFX 窗口。

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

stroke transition