Question

I’m trying to to stop an NSTimer with the following code:

- (void)viewDidLoad
{
    [super viewDidLoad];
    timer3 = [NSTimer timerWithTimeInterval:5.0 target:self selector:@selector(start) userInfo:nil repeats:YES];
    [[NSRunLoop mainRunLoop] addTimer:timer3 forMode:NSDefaultRunLoopMode];
}

-(void)invalidate
{  
    [timer3 invalidate];
    timer3 = nil; 
}

and I call -(void)invalidate from another class like this:

-(void)timer
{
    ClassOfMyTimer *class = [[ClassOfMyTimer alloc] init];
    [class invalidate];
}

but the timer doesn’t stop. Does anyone know what I’m doing wrong?

Answer 1

You need to call your invalidate method on the same instance of your class that created the timer. In your timer method you create a new instance of your class which could have its own timer and invalidate that.