Get time from pressed button (hold pressed) - ios

Question

When trying to get the time, I am not getting the expected value.
When I ran this, the time was 19:59. And in the timeDifferenceString, the Value was 71976.894206.
I think that this is the current time.
I calculate 71976 / 3600 = 19,99 h
0,99 * 60 = 59,4 m
0,4 * 60 = 24 s
So I get the time 19:59:24 o'clock. But I want get the difference between the first time and the second time and not the current time in seconds.
I want only get the time when I (hold) pressed the button
and the time that the button is not pressed (by starting the first time if I press on the button and stopped if I press on an other button).
- (IBAction)pressTheButton:(id)sender {
NSDate * now = [NSDate date];
NSDateFormatter *formatter = [[NSDateFormatter alloc] init];
[formatter setDateFormat:#"hh:mm:ss:SSS"];
NSString *currentTime = [formatter stringFromDate:now];
NSCalendar *calendar = [[NSCalendar alloc] initWithCalendarIdentifier:NSGregorianCalendar];
NSDateComponents *components; //= [calendar components:NSYearCalendarUnit|NSMonthCalendarUnit|NSDayCalendarUnit fromDate:now];
[components setHour:10];
NSDate* firstDate = [NSDate date];
NSString *getTime = [formatter stringFromDate:now];
getTime = [formatter stringFromDate:firstDate];
if (iX==0)
{
components = [calendar components:NSYearCalendarUnit|NSMonthCalendarUnit|NSDayCalendarUnit fromDate:now];
firstDate = [calendar dateFromComponents:components];
getTime = [formatter stringFromDate:firstDate];
//firstDate = [NSDate date];//[dateFormatter dateFromString:#"00:01:00:090"];
}
components = [calendar components:NSYearCalendarUnit|NSMonthCalendarUnit|NSDayCalendarUnit fromDate:now];
//NSDate* secondDate = [dateFormatter dateFromString:#"10:01:02:007"];
NSDate * secondDate = [calendar dateFromComponents:components];
getTime = [formatter stringFromDate:firstDate];
NSTimeInterval timeDifference = [firstDate timeIntervalSinceDate:secondDate];
NSString *timeDifferenceString = [NSString stringWithFormat:#"%f", timeDifference];
timeDiff[iX] = [timeDifferenceString intValue];
[timeLabel setText:timeDifferenceString];
iX++;
}
If you have a better solution for my problem pleas help me.

Answer 1

Look at UIControlEventTouchDown, UIControlEventTouchUpInside here: http://developer.apple.com/library/ios/#documentation/uikit/reference/UIControl_Class/Reference/Reference.html
Then I suppose you want to store an NSDate of when you pressed down in some sort of ivar or property (UIControlEventTouchDown) and another one when you release the button (UIControlEventTouchUpInside or UIControlEventTouchUpOutside) and then call -timeIntervalSinceDate: on that date. So it would look roughly like this:
- (IBAction)pressedDown:(id)sender {
self.pressedDownDate = [NSDate date];
}
- (IBAction)touchedUp:(id)sender {
NSDate *now = [NSDate date];
NSLog(#"Time passed: %d", [now timeIntervalSinceDate:self.pressedDownDate]);
}