Method ifThen

src/main/java/rx/Statement.java:157–159

Return an Observable that emits the emissions from a specified Observable if a condition evaluates to true, otherwise return an empty Observable. @param the result value typ

(Func0<Boolean> condition, Observable<? extends R> then)

     *         Observable otherwise
     */
    public static <R> Observable<R> ifThen(Func0<Boolean> condition, Observable<? extends R> then) {
        return ifThen(condition, then, Observable.<R> empty());
    }

    /**
     * Return an Observable that emits the emissions from a specified Observable