Main.java

package ken;

import rx.*;
import java.util.concurrent.TimeUnit;

enum MotionEvent { Down, Move, Up };
class Main {
  public static void test1() {
    Observable.just("Hello")
      .map(s -> s+"!!!")
      .subscribe(s -> System.out.println(s));
  }

  public static void test2() {
    final float speed = 1.0f;
    Observable.from(new MotionEvent[] {
          MotionEvent.Down,
          MotionEvent.Move, 
          MotionEvent.Move, 
          MotionEvent.Move, 
          MotionEvent.Up
        }
      ).zipWith(
        Observable.interval(2, TimeUnit.SECONDS),
        (x, y) -> x
      )
      .map(e -> {
          if(e == MotionEvent.Move) {
            return 2; //TODO
          } else {
            return 0;
          }
        }
      )
      .switchMap(
        distance -> {
          if(distance == 0) {
            return Observable.empty();
          } else {
            return Observable
                .just("move")
                .zipWith(
                  Observable.interval(
                    (long)(1.0 / distance * speed), TimeUnit.SECONDS),
                  (x, y) -> x
                );
          }
        }
      )
      .subscribe(s -> System.out.println(s));

      try {
        Thread.sleep(11000);
      } catch(InterruptedException e) {};
  }
  public static void main(String[] args) {
    //test1();
    test2();
  }
}