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    <p>There really is no way for you to check "is my delegate 'active' for this locationmanager?".</p> <p>What you need to do is keep track yourself of whether you're done with the location updates. </p> <p>I'm not sure if this is what you need, but here's what i do:</p> <p>1- when i start requesting updates, i do as you do, i.e. through requestlocationupdates and a delegate.</p> <p>2- In the case where i don't get the updates i need, i want to time out after some time, so that my app doesn't wait for a location forever, in this case i use a Selector with a timeout:</p> <pre><code>[self performSelector:@selector(fetchLocationTimeout) withObject:nil afterDelay:LOCATION_LISTEN_TIME]; </code></pre> <p>and in the selector:</p> <pre><code>(void)fetchLocationTimeout{ if(!finished){ [self stopUpdatingLocation]; [delegate locationFinished:bestEffortAtLocation];//see more on this below } } </code></pre> <p>3- in my didupdate-delegate i both store away the "best" location i have gotten, and if i decide that the new location is "good enough", i finish my location-fetching process:</p> <pre><code>(void)locationManager:(CLLocationManager *)manager didUpdateToLocation:(CLLocation *)newLocation fromLocation:(CLLocation *)oldLocation{ if(newLocation is the best i have){ self.bestEffortAtLocation = newLocation; } // test the measurement to see if it is more accurate than the previous measurement if (bestEffortAtLocation == nil || newLocation is the best i have) { // store the location as the "best effort" if (bestEffortAtLocation is good enough and i want to use it) { [self stopUpdatingLocation]; // we can also cancel our previous performSelector:withObject:afterDelay: - it's no longer necessary SEL selector = NSSelectorFromString(@"fetchLocationTimeout"); [NSObject cancelPreviousPerformRequestsWithTarget:self selector:selector object:nil]; [delegate locationFinished:bestEffortAtLocation]; } } } </code></pre> <p>Finally, this is my method which is called above, both from within the didupdate-delegate and from the selector timeout to reduce the risk of a race condition:</p> <pre><code>(void)stopUpdatingLocation{ finished = true; NSLog(@"stopUpdatingLocation! manager: %@", [locationManager description]); [locationManager stopUpdatingLocation]; locationManager.delegate = nil; } </code></pre> <p>Final note: the "delegate" i'm calling when i'm done is my own interface describing a class that knows how to take care of the result of a location-fetching process. it has only one method to be implemented "locationFinished", as you can see.</p> <p>Hope this helps even though my code-pasting skills aren't exactly ninja.</p>
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