iphone - Why is my CLLocationmanager delegate not getting called?

Question

I'm not getting any location callbacks on either sim or device. I've got this code being called:

- (void)startLocationCallbacks: (NSObject*) ignore
{
  locationManager.delegate = self;
  locationManager.desiredAccuracy = kCLLocationAccuracyBestForNavigation;
  locationManager.distanceFilter = MINIMUM_METERS;

  [locationManager startUpdatingLocation];
  NSLog(@"[DEBUG] [locationManager startUpdatingLocation] (%@, %@)", locationManager, locationManager.delegate);
}

and log statements at the top of both

- (void)locationManager:(CLLocationManager *)manager didFailWithError:(NSError *)error

and

- (void)locationManager:(CLLocationManager *)manager didUpdateToLocation:(CLLocation *)newLocation fromLocation:(CLLocation *)oldLocation

but neither log statement ever gets called. Location Notifications are enabled for my app (as shown in Settings, plus I said "allow.")

What are some possible reasons that I'm not getting location updates?

Config/other info:

• I have allocated locationManager, and saved it in a retain property.
• I have called startUpdatingLocation
• I'm using 4.1 SDK
• Problem is on both Sim & iPod-touch (2nd Gen) & iPhone-3, all running 4.1
• Location notifications are allowed in my app (both as indicated in Settings and because I clicked "allow" in the alert.)
• I've used CLLocationManager successfully before (in many shipping apps!) This is a real hair-puller for me.

Thanks!

Answer 1

Whew! Ok, I found it.

It turns out that one of the ways to make a CLLocationManager not fire off location callbacks is to do all the set-up in not-the-main-thread. When I moved my setup routine to a performSelectorOnMainThread, all worked exactly as expected.

What a nightmare!

Hope this answer helps others...

Edit/clarification:

Originally, I had something like this:

- (BOOL) appDidFinishLaunchingWithOptions: (NSDictionary*) options
{
     // ...[app setup, snip]
    [NSThread detachNewThreadSelector: @selector(postLaunchSetupThread) toTarget: self withObject: nil];
}

- (void)postLaunchSetupThread
{
    NSAutoreleasePool *pool = [NSAutoreleasePool new];
    // ...[other setup, snip]
    [self setupLocationManager];
    [pool release];
}

- (void)setupLocationManager
{
     self.myLocationManager = [[[CLLocationManager alloc] init] autorelease];
     [myLocationManager startLocationUpdates];
}

But calling setupLocationManager in a thread prevented the callbacks. So my fix was to move the line

[self setupLocationManager];

out of the thread and back into appDidFinishLaunchingWithOptions