JavaFX Running a large amount of countdown timers at once?

Question

So I can see a couple different ways to do what I need and I\'ve done a bunch of google/stack overflow searching but can\'t find really what I\'m looking for. I need to run mult

Answer 1

What you are looking for is RxJava and its bridge to JavaFx which is RxJavaFx. Import dependency:

    io.reactivex.rxjava2
    rxjavafx
    2.2.2

and run

import java.util.concurrent.TimeUnit;

import io.reactivex.Observable;
import io.reactivex.rxjavafx.observables.JavaFxObservable;
import io.reactivex.rxjavafx.schedulers.JavaFxScheduler;
import io.reactivex.schedulers.Schedulers;
import javafx.application.Application;
import javafx.scene.Scene;
import javafx.scene.control.Label;
import javafx.scene.control.ToggleButton;
import javafx.scene.layout.HBox;
import javafx.scene.layout.VBox;
import javafx.stage.Stage;

public class TimersApp extends Application {

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

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

        VBox vBox = new VBox();
        for (int i = 0; i < 4; i++) {
            ToggleButton button = new ToggleButton("Start");
            Label label = new Label("0");
            HBox hBox = new HBox(button, label, new Label("seconds"));
            vBox.getChildren().add(hBox);

            JavaFxObservable.valuesOf(button.selectedProperty())
            .switchMap(selected -> {
                if (selected) {
                    button.setText("Stop");
                    return Observable.interval(1, TimeUnit.SECONDS, Schedulers.computation()).map(next -> ++next);
                } else {
                    button.setText("Start");
                    return Observable.empty();
                }
            })
            .map(String::valueOf)
            .observeOn(JavaFxScheduler.platform())
            .subscribe(label::setText);
        }

        stage.setScene(new Scene(vBox));
        stage.show();
    }
}

Let me know if you are intrested in this solution. I will provide you some materials to learn.