如何倒计时到UTC的毫秒数

Question

I'm using an api which fetches all upcoming movies and all dates in the api are stored in milliseconds, when I try to countdown from today's date to the movie's release date, the countdown is in my local timezone. For example, I'm in the east coast and when the countdown reaches 8 PM it counts as a new day and the number of days left decrements

Here's a screenshot:

As you can see, this was the countdown when it was around 9 PM in the east coast, so at 8 PM it would have been 24 hours left, how can I change this? Of course I want it to reset the day at midnight, not at 8 PM. Thank you!

Here's my code:

  public long getMillisInGMT(long date) {
    // We don't care what date format we're going to format to
    SimpleDateFormat formatter = new SimpleDateFormat("dd-M-yyyy hh:mm:ss");
    formatter.setTimeZone(TimeZone.getTimeZone("GMT"));
    String formatted = formatter.format(new Date(date));
    try {
        return formatter.parse(formatted).getTime();
    } catch (ParseException e) {
        e.printStackTrace();
    }
    return 0;
}

public void initCountdown(_Release release) {
    long releaseDate = release.getDate();
    long timeTillRelease = getMillisInGMT(releaseDate) - getMillisInGMT(Calendar.getInstance().getTimeInMillis());
    mCountdownTimer = new CountDownTimer(timeTillRelease, 1000) { // adjust the milli seconds here
        public void onTick(long millisUntilFinished) {
            // 1 sec = 1000 millis
            long seconds = millisUntilFinished / 1000;
            long minutes = seconds / 60;
            long hours = minutes / 60;
            long days = hours / 24;
            mDaysTxt.setText(String.valueOf(days));
            mHoursText.setText(String.valueOf(hours % 24));
            mMinutesText.setText(String.valueOf(minutes % 60));
            mSecondsText.setText(String.valueOf(seconds % 60));
        }

        public void onFinish() {
            mHeaderReleasesTitle.setText("Released on");
            mOutNowTxt.setVisibility(View.VISIBLE);
            mCountdownLayout.setVisibility(View.GONE);
        }
    };
    mCountdownTimer.start();
}

Answer 1

I'm not 100% sure where your error is coming from, but I know that I've run into a lot of problems using the Date and Calendar libraries. By far the best time library out there is the Joda-Time library. If it were me, I'd replace the library and see if that fixed things before troubleshooting further.

To get the current UTC (GMT) time you would use the DateTime library like below:

DateTime.now().withZone(DateTimeZone.UTC)

To convert the Release millis to UTC you would use the DateTime library like below:

new DateTime(dateInMillis).withZone(DateTimeZone.UTC);

I know it's not a direct answer to your question, but I can't tell you how many odd issues I ran into while using the Date and Calendar libraries. Joda-Time fixes most issues. It's an amazing library.