Rxjava elegant implementation of SMS verification code transmission

Do not talk nonsense directly on the code

private fun countDown() {
        btn_send_code_activity_login.isEnabled = false
        disPose = Flowable.intervalRange(0,
                .doOnNext {
                            .text = String.format(getString(R.string.label_code_time), 120 - it)
                .doOnComplete {
                    btn_send_code_activity_login.isEnabled = true
                    btn_send_code_activity_login.text = getString(R.string.label_get_code)

Use hereThe intervalRange parameter means the following

     * Signals a range of long values, the first after some initial delay and the rest periodically after.
     * <p>
     * The sequence completes immediately after the last value (start + count - 1) has been reached.
     * <dl>
     *  <dt><b>Backpressure:</b></dt>
     *  <dd>The operator signals a {@code MissingBackpressureException} if the downstream can't keep up.</dd>
     *  <dt><b>Scheduler:</b></dt>
     *  <dd>{@code intervalRange} by default operates on the {@link Schedulers#computation() computation} {@link Scheduler}.</dd>
     * </dl>
     * @param start that start value of the range
     * @param count the number of values to emit in total, if zero, the operator emits an onComplete after the initial delay.
     * @param initialDelay the initial delay before signaling the first value (the start)
     * @param period the period between subsequent values
     * @param unit the unit of measure of the initialDelay and period amounts
     * @return the new Flowable instance
    public static Flowable<Long> intervalRange(long start, long count, long initialDelay, long period, TimeUnit unit) {
        return intervalRange(start, count, initialDelay, period, unit, Schedulers.computation());