Update a Label daily with new text - nsdate

Question

I have a label I want to update daily and automatically? in some specific time. How could the code be.. I have searched every where about how to updating the label daily.
the NSdate and NStimer label working . And also datepicker if the user want to look at forward events.
I think it is something with, 'if' the date is.. }else{... and something like that
Thanks
edit:
If I already have these codes in my app then there will be something wrong
NSDateFormatter* dateFormatter = [[NSDateFormatter alloc] init];
NSDate *nowDate = [NSDate date];
self.currentDateLabel.text = [dateFormatter stringFromDate:nowDate];

Answer 1

Try this code for any comparison between dates... You should not compare date in the form of string. Compare the dates before conversion to string. Convert the self.serverDate into date format using dateFromString function of the formatter by specifying the exact date format as that of the dateString. Then compare the dates using following function.
-(void) callAfterSixtySecond:(NSTimer*) t
{
NSDate *today = [NSDate date]; // current date
NSDate *newDate = self.serverDate; // other date
NSDateFormatter *formatter = [[NSDateFormatter alloc]init];
[formatter setDateFormat:#"HH:mm"];
NSDate *todayTime = [formatter dateFromString:[formatter stringFromDate:today]];
NSDate *requiredTime = [formatter dateFromString:[formatter stringFromDate:newDate]];
NSComparisonResult result;
result = [todayTime compare:requiredTime ]; // comparing two dates
if(result == NSOrderedAscending)
NSLog(#"today is less");
else if(result == NSOrderedDescending)
NSLog(#"newDate is less");
else if(result == NSOrderedSame)
NSLog(#"Both dates are same"); // time has reached. Update Label using setText method of label
else
NSLog(#"Date cannot be compared");
}
You will need to run this method every minute using an NSTimer...
NSTimer* myTimer = [NSTimer scheduledTimerWithTimeInterval: 60.0 target: self
selector: #selector(callAfterSixtySecond:) userInfo: nil repeats: YES];