Question

我正在尝试创建一个运行线程而不是时间轴的程序。这是我在下面修改的程序。我不确定为什么它不起作用。任何提示将不胜感激。线程使用任务来启动动画。谢谢你的帮助。

import javafx.animation.KeyFrame;
import javafx.animation.Timeline;
import javafx.application.Application;
import javafx.geometry.Pos;
import javafx.scene.Scene;
import javafx.scene.control.Button;
import javafx.scene.layout.BorderPane;
import javafx.scene.layout.HBox;
import javafx.scene.layout.Pane;
import javafx.scene.paint.Color;
import javafx.scene.shape.Arc;
import javafx.scene.shape.ArcType;
import javafx.scene.shape.Circle;
import javafx.stage.Stage;
import javafx.util.Duration;

public class ch30 extends Application {
  @Override // Override the start method in the Application class
  public void start(Stage primaryStage) {       
    FanPane fan = new FanPane();

    HBox hBox = new HBox(5);
    Button btPause = new Button("Pause");
    Button btResume = new Button("Resume");
    Button btReverse = new Button("Reverse");
    hBox.setAlignment(Pos.CENTER);
    hBox.getChildren().addAll(btPause, btResume, btReverse);

    BorderPane pane = new BorderPane();
    pane.setCenter(fan);
    pane.setBottom(hBox);

    // Create a scene and place it in the stage
    Scene scene = new Scene(pane, 200, 200);
    primaryStage.setTitle("Exercise15_28"); // Set the stage title
    primaryStage.setScene(scene); // Place the scene in the stage
    primaryStage.show(); // Display the stage

     Runnable first = new Begin();

     Thread t1 = new Thread(first);

     t1.start();









   //Timeline animation = new Timeline(
      //new KeyFrame(Duration.millis(100), e -> fan.move()));
    //animation.setCycleCount(Timeline.INDEFINITE);
    //animation.play(); // Start animation

    scene.widthProperty().addListener(e -> fan.setW(fan.getWidth()));
    scene.heightProperty().addListener(e -> fan.setH(fan.getHeight()));

    //btPause.setOnAction(e -> first.wait());
    btResume.setOnAction(e -> first.run());
    btReverse.setOnAction(e -> fan.reverse());
  }

  /**
   * The main method is only needed for the IDE with limited
   * JavaFX support. Not needed for running from the command line.
   */
  public static void main(String[] args) {
    launch(args);


  }
} 

class FanPane extends Pane {
  private double w = 200;
  private double h = 200;
  private double radius = Math.min(w, h) * 0.45;
  private Arc arc[] = new Arc[4];   
  private double startAngle = 30;
  private Circle circle = new Circle(w / 2, h / 2, radius);

  public FanPane() {
    circle.setStroke(Color.BLACK);
    circle.setFill(Color.WHITE);
    getChildren().add(circle);

    for (int i = 0; i < 4; i++) {
      arc[i] = new Arc(w / 2, h / 2, radius * 0.9, radius * 0.9, startAngle + i * 90, 35);
      arc[i].setFill(Color.RED); // Set fill color
      arc[i].setType(ArcType.ROUND);
      getChildren().addAll(arc[i]); 
    } 
  }

  private double increment = 5;

  public void reverse() {
    increment = -increment;
  }

  public void move() {
    setStartAngle(startAngle + increment);
  }

  public void setStartAngle(double angle) {
    startAngle = angle;
    setValues();
  }

  public void setValues() {
    radius = Math.min(w, h) * 0.45;
    circle.setRadius(radius);
    circle.setCenterX(w / 2);
    circle.setCenterY(h / 2);

    for (int i = 0; i < 4; i++) {
      arc[i].setRadiusX(radius * 0.9);
      arc[i].setRadiusY(radius * 0.9);
      arc[i].setCenterX(w / 2);
      arc[i].setCenterY(h / 2);
      arc[i].setStartAngle(startAngle + i * 90);
    }     
  }

  public void setW(double w) {
    this.w = w;
    setValues();
  }

  public void setH(double h) {
    this.h = h;
    setValues();
  }
}

   class Begin implements Runnable {
        private int times = 1000;
        FanPane fan = new FanPane();

        public Begin(){
           // times = t;
       }

        @Override
        public void run(){
            //for (int i = 0; i < times; i++)
            //{
                fan.move();
            }
        }

Answer 1

您的线程需要一个循环，重复暂停然后更新UI。如果你想使用显式线程而不是更明显的Timeline，你需要自己编写该循环的代码。

无法从您正在创建的后台线程调用UI的更新：要更新FX Application线程上的UI，您必须将调用包装到更新Platform.runLater(...)中的UI的方法。

从时间轴转换为线程

1 个答案: