Updating NSDateFormatter with NSTimer

[iOS.Lover]

Hi, I have created a custom class which show time date formatter and I need a timer like method to update the seconds, so here is my code :

CustomClass.m

- (NSString *) showLocaleTime {

        [timeFormater setDateFormat:@"HH:mm:ss"];
        NSString *timer = [timeFormater stringFromDate:[NSDate date]];
        timer = [NSString stringWithFormat:@"%@",timer];
        [timeFormater release];


    return timer;
}


- (void) updateLocaleTime {

    [NSTimer scheduledTimerWithTimeInterval:0.5 target:self selector:@selector(showLocaleTime) userInfo:nil repeats:YES];

}

viewController.m :

CustomClass *time = [[CustomClass alloc]init];
label.text = [time showLocaleTime];

[time updateLocaleTime];

\


But the problem is the updateLocaleTime does not call to update seconds ! am I missing something ? Thanks

[Duncan C]

Originally Posted by iOS.Lover

Hi, I have created a custom class which show time date formatter and I need a timer like method to update the seconds, so here is my code :

CustomClass.m

- (NSString *) showLocaleTime {

        [timeFormater setDateFormat:@"HH:mm:ss"];
        NSString *timer = [timeFormater stringFromDate:[NSDate date]];
        timer = [NSString stringWithFormat:@"%@",timer];
        [timeFormater release];


    return timer;
}


- (void) updateLocaleTime {

    [NSTimer scheduledTimerWithTimeInterval:0.5 target:self selector:@selector(showLocaleTime) userInfo:nil repeats:YES];

}

viewController.m :

CustomClass *time = [[CustomClass alloc]init];
label.text = [time showLocaleTime];

[time updateLocaleTime];

\


But the problem is the updateLocaleTime does not call to update seconds ! am I missing something ? Thanks

You have showLocalTime set up as a method with no parameters, that returns a string as a result.

NSTimer methods need to take a single parameter, the timer itself, and not return any result. To quote the Apple docs from NSTimer:

The message to send to target when the timer fires. The selector must have the following signature:

- (void)timerFireMethod:(NSTimer*)theTimer

You need to write a timer method that calls your showLocaleTime method, takes the result, and does something with it.

[iOS.Lover]

Originally Posted by Duncan C

You have showLocalTime set up as a method with no parameters, that returns a string as a result.

NSTimer methods need to take a single parameter, the timer itself, and not return any result. To quote the Apple docs from NSTimer:
You need to write a timer method that calls your showLocaleTime method, takes the result, and does something with it.

Sorry my code was wrong , here is showLocaleTime , would you please reconsider it again ?

- (NSString *) showLocaleTime {

NSDateFormatter *timeFormater = [[NSDateFormatter alloc] init];
timeFormater = [setDateFormat:@"HH:mm:ss "];

NSString *currDay = [timeFormater stringFromDate:[NSDate date]];
currDay = [NSString stringWithFormat:@"%@",currDay];
[timeFormater release];


    return timer;
}


- (void) updateLocaleTime {

    [NSTimer scheduledTimerWithTimeInterval:0.5 target:self selector:@selector(showLocaleTime) userInfo:nil repeats:YES];

}

[Domele]

His post still applies. You are calling showLocaleTime with your timer. showLocaleTime returns a NSString. It should returning nothing. In your showLocaleTime method, you should set a UILabel's text property with your currDay NSString variable.

[Duncan C]

Originally Posted by iOS.Lover

Sorry my code was wrong , here is showLocaleTime , would you please reconsider it again ?

- (NSString *) showLocaleTime {

NSDateFormatter *timeFormater = [[NSDateFormatter alloc] init];
timeFormater = [setDateFormat:@"HH:mm:ss "];

NSString *currDay = [timeFormater stringFromDate:[NSDate date]];
currDay = [NSString stringWithFormat:@"%@",currDay];
[timeFormater release];


    return timer;
}


- (void) updateLocaleTime {

    [NSTimer scheduledTimerWithTimeInterval:0.5 target:self selector:@selector(showLocaleTime) userInfo:nil repeats:YES];

}

A method that's invoked by a timer must have specific signature or it won't get called. Go back and read my previous post.

The method the timer calls can't return a value. It must have a single parameter, which is the timer itself. This is not a "well maybe" situation. Do it that way, or it doesn't work. Period.