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copied!<p>Can't tell where the invalid coordinates are coming from but I suggest adding the following checks to the <code>zoomToUserLocation</code> method.</p> <p>Just checking if <code>userlocation</code> is <code>nil</code> is not enough. You have to also check if the <code>location</code> property inside <code>userlocation</code> is nil or not. <em>Then</em>, you can use the <code>coordinate</code> property (especially when you're using the coordinates outside the <code>didUpdateUserLocation</code> delegate method). </p> <p>Also, just checking if <code>coordinate</code> is <code>0,0</code> (technically a valid coordinate) is not recommended as the struct will be "zero" if it's never been set or it could even be filled with random data. The Core Location framework's <code>CLLocationCoordinate2DIsValid</code> function is used as the last line of defense to prevent an invalid region.</p> <p>You could also check the <code>timestamp</code> and <code>horizontalAccuracy</code> if you want.</p> <pre><code>- (void)zoomToUserLocation:(MKUserLocation *)userlocation { if (!userlocation) return; if (!userlocation.location) { NSLog(@"actual location has not been obtained yet"); return; } //optional: check age and/or horizontalAccuracy //(technically should check if location.timestamp is nil first) NSTimeInterval locationAgeInSeconds = [[NSDate date] timeIntervalSinceDate:userlocation.location.timestamp]; if (locationAgeInSeconds > 300) //adjust max age as needed { NSLog(@"location data is too old"); return; } if (!CLLocationCoordinate2DIsValid(userlocation.coordinate)) { NSLog(@"userlocation coordinate is invalid"); return; } MKCoordinateRegion region; region.center = userlocation.coordinate; region.span = MKCoordinateSpanMake(2.0, 2.0); //region = [self.mapView regionThatFits:region]; //don't need to call regionThatFits explicitly, setRegion will do it [self.mapView setRegion:region animated:YES]; } </code></pre> <p>Additionally (possibly unrelated and you may have already done this but), based on a couple of your previous questions related to this, you might want to clear and re-set the map view's <code>delegate</code> in the map view controller's <code>viewWillDisappear</code> and <code>viewWillAppear</code> methods to prevent certain errors:</p> <pre><code>-(void)viewWillAppear:(BOOL)animated { mapView.delegate = self; } -(void)viewWillDisappear:(BOOL)animated { mapView.delegate = nil; } </code></pre>

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