How to countdown from a NSDate and display it in hours and minutes

ios, nsdate, nstimer, objective-c

Solution

- (NSString *)stringFromTimeInterval:(NSTimeInterval)interval 
  {
    NSInteger ti = (NSInteger)interval;
    NSInteger seconds = ti % 60;
    NSInteger minutes = (ti / 60) % 60;
    NSInteger hours = (ti / 3600);
    return [NSString stringWithFormat:@"%02i:%02i:%02i", hours, minutes, seconds];
  }

Problem

I'm trying to countdown from a NSDate and display it in hours and minutes. Like this: 1h:18min At the moment my date is updating to a UILabel and counting down but displaying like this: Here's the code I'm using. A startTimer method and a updateLabel method ``` - (void)startTimer { // Set the date you want to count from // convert date string to date then set to a label NSDateFormatter *dateStringParser = [[NSDateFormatter alloc] init]; [dateStringParser setDateFormat:@"yyyy-MM-dd'T'HH:mm:ss.000Z"]; NSDate *date = [dateStringParser dateFromString:deadlineDate]; NSDateFormatter *labelFormatter = [[NSDateFormatter alloc] init]; [labelFormatter setDateFormat:@"HH-dd-MM-yyyy"]; NSDate *countdownDate = [[NSDate alloc] init]; countdownDate = date; // Create a timer that fires every second repeatedly and save it in an ivar NSTimer *timer = [[NSTimer alloc] init]; timer = [NSTimer scheduledTimerWithTimeInterval:1.0 target:self selector:@selector(updateLabel) userInfo:nil repeats:YES]; } - (void)updateLabel { // convert date string to date then set to a label NSDateFormatter *dateStringParser = [[NSDateFormatter alloc] init]; [dateStringParser setDateFormat:@"yyyy-MM-dd'T'HH:mm:ss.000Z"]; NSDate *date = [dateStringParser dateFromString:deadlineDate]; NSDateFormatter *labelFormatter = [[NSDateFormatter alloc] init]; [labelFormatter setDateFormat:@"HH-dd-MM"]; NSTimeInterval timeInterval = [date timeIntervalSinceNow]; ///< Assuming this is in the future for now. self.deadlineLbl.text = [NSString stringWithFormat:@"%f", timeInterval]; } ``` thanks for any help

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