Putting current time into label

Ii am trying to get date and time using date but when i run application it takes first time executed application time and date in short time is not changed.

NSDate *StrDate = [NSDate date];
        NSDateFormatter *Dateformat = [[NSDateFormatter alloc]init]开发者_JAVA技巧;
        [Dateformat setDateFormat:@"DD-MM-YYYY"];
        NSMutableString *DateStr = [Dateformat stringFromDate:StrDate];
        [UserCntrl.timeDisplay setText:DateStr];
        [Dateformat setDateFormat:@"HH:MM"];
        NSMutableString *timeStr=[Dateformat stringFromDate:StrDate];

Place a scheduled timer in your uiview did show (or did load) method:

[NSTimer scheduledTimerWithTimeInterval:1.0f // 1 second
    target:self
    selector:@selector(updateTime:) 
    userInfo:nil
    repeats:YES];

Then, put this method in your View Controller:

- (void) updateTime:(id)sender
{
    NSDate *StrDate = [NSDate date];
        NSDateFormatter *Dateformat = [[NSDateFormatter alloc]init];
        [Dateformat setDateFormat:@"DD-MM-YYYY HH:mm:SS"];
        NSMutableString *DateStr = [Dateformat stringFromDate:StrDate];
        [UserCntrl.timeDisplay setText:DateStr]; // or whatever code updates your timer.  I didn't check this for bugs.
}

This will call the "updateTime:" method once a second, updating your controller.

[NSDate date] makes a date object of the time you call it. You must call it again to update the date. In other words, you must do StrDate = [NSDate date]; whenever you want to get the current date in your method.

You have a bug in your code: Instead of [Dateformat setDateFormat:@"HH:MM"]; it should be [Dateformat setTimeFormat:@"HH:MM"];