Question

- (void)viewWillAppear:(BOOL)animated
{
MKUserTrackingBarButtonItem *trackingBarButtonItem = [[MKUserTrackingBarButtonItem alloc]initWithMapView:_mapView];

NSArray *barButtonItems = [NSArray arrayWithObjects:trackingBarButtonItem, nil];
mapToolbar.items = barButtonItems;
...
}

Code works fine on iPhone, but on iPad when view is unloading I get an error:

Cannot remove an observer <MKUserTrackingBarButtonItem 0x9cc0930> for the key path  
"controlSize" from <UIButton 0x991b420> because it is not registered as an observer.'

Answer 1

I contacted Apple DTS and their answer was:

“To the best of my knowledge there is no workaround for this in the current shipping SDK. I would check the latest iOS SDK beta though and see if this is still an issue.”