单击按钮时在标签中显示实时持续时间(秒表),并在使用 JavaFX-8 单击另一个按钮时停止

Show a live duration (stopwatch) in a label when clicking a button and stop it when clicking another button using JavaFX-8

我想使用 JavaFX-8 实现以下目标:

  1. 按下按钮“呼叫”
  2. 一个直播时长(秒表)从00:00:00开始出现在标签中,保持运行每秒
  3. 按另一个按钮“结束通话”
  4. 直播时长应该停止
  5. 再次按下“呼叫”按钮
  6. 直播时长应重置为 00:00:00 并保持每秒 运行

这个想法是模拟 phone 通话从按下“通话”到按下“结束通话”的持续时间。

public class Main extends Application {
    @Override
    public void start(Stage primaryStage) {

        Button callBtn = new Button("Call");
        Button endCallBtn = new Button("End Call");

        Label duration = new Label("Duration");
        Label callDuration = new Label("00:00:00");

        VBox vBox = new VBox(callBtn, duration, callDuration, endCallBtn);
        vBox.setPadding(new Insets(10));
        vBox.setSpacing(10);

        Scene scene = new Scene(vBox);
        primaryStage.setScene(scene);
        primaryStage.show();
    }

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

以下是满足您要求的一种方法。话虽如此,可能还有其他更好的方法,但这可以给出如何开始的想法。

import javafx.animation.Animation;
import javafx.animation.KeyFrame;
import javafx.animation.Timeline;
import javafx.application.Application;
import javafx.geometry.Insets;
import javafx.scene.Scene;
import javafx.scene.control.Button;
import javafx.scene.control.Label;
import javafx.scene.layout.VBox;
import javafx.stage.Stage;
import javafx.util.Duration;

import java.util.concurrent.TimeUnit;

public class StopClock_Demo extends Application {
    private long time;

    @Override
    public void start(Stage primaryStage) {
        Label callDuration = new Label("00:00:00");
        Timeline clock = new Timeline(new KeyFrame(Duration.ZERO, e -> {
            long millis = System.currentTimeMillis() - time;
            String txt = String.format("%02d:%02d:%02d",
                    TimeUnit.MILLISECONDS.toHours(millis),
                    TimeUnit.MILLISECONDS.toMinutes(millis) -
                            TimeUnit.HOURS.toMinutes(TimeUnit.MILLISECONDS.toHours(millis)),
                    TimeUnit.MILLISECONDS.toSeconds(millis) -
                            TimeUnit.MINUTES.toSeconds(TimeUnit.MILLISECONDS.toMinutes(millis)));
            callDuration.setText(txt);
        }), new KeyFrame(Duration.seconds(1)));
        clock.setCycleCount(Animation.INDEFINITE);

        Button callBtn = new Button("Call");
        callBtn.setOnAction(e -> {
            if (clock.getStatus() != Animation.Status.RUNNING) {
                time = System.currentTimeMillis();
                clock.play();
            }
        });
        Button endCallBtn = new Button("End Call");
        endCallBtn.setOnAction(e -> {
            if (clock.getStatus() == Animation.Status.RUNNING) {
                clock.stop();
            }
        });
        Label duration = new Label("Duration");

        VBox vBox = new VBox(callBtn, duration, callDuration, endCallBtn);
        vBox.setPadding(new Insets(10));
        vBox.setSpacing(10);

        Scene scene = new Scene(vBox);
        primaryStage.setScene(scene);
        primaryStage.show();
    }

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