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iphonegpscllocationmanagercllocation

Heading accuracy is coming up negative

I am trying to show compass on my screen

if ([CLLocationManager headingAvailable]) {
    CLController.locMgr.headingFilter = 0.1;
    [CLController.locMgr startUpdatingHeading];
}

it goes into method, and goes into method

- (void)locationManager:(CLLocationManager *)manager didUpdateHeading:(CLHeading *)newHeading {
if (newHeading.headingAccuracy < 0){
    NSLog(@"heading accuracy < 0");
    return;
}
// Use the true heading if it is valid.
CLLocationDirection  direction = ((newHeading.trueHeading > 0) ?
                                   newHeading.trueHeading : newHeading.magneticHeading);

[self.delegate headingUpdate:direction];

}

Earlier it was working fine, but dont know what happened now,

It's showing "heading accuracy < 0"..

Solution

  • A negative headingAccuracy value simply means that the compass cannot get a good reading at the moment. Perhaps the phone is near some strong magnetic field or you need to wave it in a figure 8 to calibrate the compass. It doesn't mean your code is incorrect.

    Just ignore the heading updates where the headingAccuracy < 0, and only use the other values you get. This is normal behaviour.