javafx中Clock类怎么做简易时钟

要在JavaFX中创建一个简易时钟，可以使用Clock类。以下是一个简单的JavaFX程序，它使用Clock类创建一个时钟：

import javafx.animation.Animation;
import javafx.animation.KeyFrame;
import javafx.animation.Timeline;
import javafx.application.Application;
import javafx.scene.Scene;
import javafx.scene.layout.StackPane;
import javafx.scene.paint.Color;
import javafx.scene.shape.Circle;
import javafx.scene.shape.Line;
import javafx.scene.text.Font;
import javafx.scene.text.Text;
import javafx.stage.Stage;
import javafx.util.Duration;

import java.time.LocalTime;
import java.time.format.DateTimeFormatter;

public class SimpleClock extends Application {

    @Override
    public void start(Stage primaryStage) throws Exception {

        // Create the clock components
        Circle outerCircle = new Circle(100, 100, 80);
        outerCircle.setFill(null);
        outerCircle.setStroke(Color.BLACK);
        outerCircle.setStrokeWidth(3);

        Circle innerCircle = new Circle(100, 100, 5);
        innerCircle.setFill(Color.BLACK);

        Line hourHand = new Line(100, 100, 100, 50);
        hourHand.setStrokeWidth(5);

        Line minuteHand = new Line(100, 100, 100, 30);
        minuteHand.setStrokeWidth(3);

        Text timeText = new Text();
        timeText.setFont(new Font(20));
        timeText.setX(70);
        timeText.setY(180);

        // Create the timeline to update the clock every second
        Timeline timeline = new Timeline(
                new KeyFrame(Duration.seconds(1), event -> {
                    LocalTime now = LocalTime.now();
                    double hours = now.getHour() % 12 + now.getMinute() / 60.0;
                    double minutes = now.getMinute();
                    double seconds = now.getSecond();

                    hourHand.setEndX(100 + 40 * Math.sin(hours * 30 * Math.PI / 180));
                    hourHand.setEndY(100 - 40 * Math.cos(hours * 30 * Math.PI / 180));

                    minuteHand.setEndX(100 + 60 * Math.sin(minutes * 6 * Math.PI / 180));
                    minuteHand.setEndY(100 - 60 * Math.cos(minutes * 6 * Math.PI / 180));

                    String timeString = now.format(DateTimeFormatter.ofPattern("HH:mm:ss"));
                    timeText.setText(timeString);
                })
        );
        timeline.setCycleCount(Animation.INDEFINITE);
        timeline.play();

        // Create the root node and add the clock components
        StackPane root = new StackPane();
        root.getChildren().addAll(outerCircle, innerCircle, hourHand, minuteHand, timeText);

        // Create the scene and add the root node
        Scene scene = new Scene(root, 200, 200);

        // Set the stage title and scene, and show the stage
        primaryStage.setTitle("Simple Clock");
        primaryStage.setScene(scene);
        primaryStage.show();
    }

    public static void main(String[] args) {
        launch(args);
    }
}

这个程序创建了一个圆形时钟，它包括一个外部圆，一个内部圆，一个时针，一个分针和一个显示当前时间的文本。时钟每秒钟更新一次。