Question

I have a timer that launches in viewDidLoad that looks like this

[NSTimer scheduledTimerWithTimeInterval:0.001f target:self selector:@selector(Dragon:) userInfo:nil repeats:YES];

I want to be able to change my Interval with a variable. However, any time I try to place a variable where the 0.001f is I get errors… any ideas?

Answer 1

I have an app that does exactly what you are asking. I allow the user to change the speed of the timer within the app so I need to make that speed a variable. Here’s how I did it:

1. I create a timer property on my main view controller class.

2. I initialize the timer when the main view controller class loads.

3. Each time thereafter, I invalidate my timer and reset it when the value changes.

Some snippets from inside of my main view controller .m file:

    //How often to switch views (float)
    #define kInterval [[NSUserDefaults standardUserDefaults] integerForKey:@"interval"]

- (void) viewDidAppear:(BOOL)animated{
    [self setTimer];
}

- (void) setTimer{
    [self.timer invalidate];
    [self setTimer: [NSTimer scheduledTimerWithTimeInterval:kInterval target:self selector:@selector(timerFired) userInfo:nil repeats:YES]];
}