Question

I’m trying to make a timer by myself but it doesn’t work. It seems like it goes nil every time it repeats, anyone? It works on OS X but not on iOS.

I just need a working loop method – any suggestions?

Header:

@interface ViewController : UIViewController
@property (strong, nonatomic) IBOutlet UILabel *timerOutlet;
- (void)timer:(id)sender;
@end

Implementation:

@synthesize timerOutlet;

- (void)viewDidLoad
{
    [super viewDidLoad];
    started = TRUE;
    [self timer:nil];
}

- (void)timer:(id)sender {
    int test = 1;
    NSString *number = [NSString stringWithFormat:@"%i",test];
    timerOutlet.text = number;
    [self performSelector:@selector(timer:) withObject:Nil afterDelay:1.0];
    test ++;                
}

Answer 1

The problem is that you re-declare test and assign 1 to it every time the timer method executes. So if you either omit the declaration and make test an instance variable, or make it static, that should help. Apart from that, however, you should really use an NSTimer object instead of raping the framework.

- (void)viewDidLoad
{
    [super viewDidLoad];
    started = TRUE;
    test = 1;
    [NSTimer scheduledTimerWithTimeInterval:1.0f target:self selector:@selector(timer:) userInfo:nil repeats:YES];
}

- (void)timer:(id)sender {
    NSLog(@"%i",test);
    test++;
}