Calling a NSTimer method

Question

I'm new to working with timers on the iPhone and would need some support.

I have a method as below that takes the time and update a UILabel in my userinterface. I also have an NSTimer that calls that method once a second (I only show hours and minutes). This works just fine, except for the first second the App is live (as I understand it takes one second before the timer calls the method).

I would like to call my method from viewDidLoad, but how can I supply the right arguments? Or is there a better way of doing this?

// Timer for updating time
[NSTimer scheduledTimerWithTimeInterval:1.0f 
                                 target:self 
                               selector:@selector(updateTime:) 
                               userInfo:nil 
                                repeats:YES];   


-(void)updateTime: (NSTimer *) timer {

    currentTime = [NSDate date];
    NSDateFormatter *dateFormatter = [[NSDateFormatter alloc] init];
    // display in 12HR/24HR (i.e. 11:25PM or 23:25) format according to User Settings
    [dateFormatter setTimeStyle:NSDateFormatterShortStyle];
    NSString *currentTimeString = [dateFormatter stringFromDate:currentTime];
    [dateFormatter release];

    timeLabel.text =  currentTimeString;
}

Appreciate anything that would point me in the right direction.

score 2 · Accepted Answer · answered Jun 22 '10 at 04:12

2

In your method, you don't use the timer variable right? So, why just call [self updateTime:nil]. That should work

answered Jun 22 '10 at 04:12

vodkhang

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Yes you are right. Such a simple and neat solution. Tested and is working fine. Thanks! Seems to also be a solution with "fire" that you can trigger the timer event but I have not had the time to test it yet. – Structurer Jun 22 '10 at 10:09

score 2 · Answer 2 · edited Dec 23 '13 at 08:48

2

One more option ... you can do:

[NSTimer scheduledTimerWithTimeInterval:0.01f 
                                 target:self 
                               selector:@selector(updateTime:) 
                               userInfo:nil  
                                repeats:NO];    

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

edited Dec 23 '13 at 08:48

Alex Cio

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answered Jun 22 '10 at 04:32

ohho

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Thanks Horace. I think I will go for vodkhangs solution though. – Structurer Jun 22 '10 at 10:07

Calling a NSTimer method

2 Answers2