CLLocationManager doesn't show popup if location services were previously disabled - ios

Question

When I launch my app I check current location authorisation status like this:
- (void)checkCurrentStatus
{
if ([CLLocationManager authorizationStatus] == kCLAuthorizationStatusNotDetermined)
{
[self.locationManager requestWhenInUseAuthorization];
}
else
if ([CLLocationManager authorizationStatus] == kCLAuthorizationStatusDenied && ![CLLocationManager locationServicesEnabled])
{
[self.locationManager startUpdatingLocation];
}
}
If overall location services are enabled (for the whole device) than it just asks user for permission, the alert pops up. If they are disabled (else if condition) then I need to call startUpdatingLocation because call to [self.locationManager requestWhenInUseAuthorization]; has no effect when authorisation status is kCLAuthorizationStatusDenied (without any if conditions). Ok, so I call startUpdatingLocation and then alert pops up which says:
Turn On Location Services to Allow "AppName" to Determine Your Location
Ok, I go to the settings on turn overall location services on. After that authorizationStatus becomes kCLAuthorizationStatusNotDetermined but when I call requestWhenInUseAuthorization it has no effect! No popup appears, user is not prompted for to authorise location, the status remains the same, I can't use location manager. How can I handle that?

Answer 1

From Apple's doc on CLLocationManager about - (void)requestWhenInUseAuthorization
If the current authorization status is anything other than
kCLAuthorizationStatusNotDetermined, this method does nothing and does
not call the locationManager:didChangeAuthorizationStatus: method
Here's what you need :
- (void)requestAlwaysAuthorization
{
CLAuthorizationStatus status = [CLLocationManager authorizationStatus];
// If the status is denied or only granted for when in use, display an alert
if (status == kCLAuthorizationStatusAuthorizedWhenInUse || status == kCLAuthorizationStatusDenied) {
NSString *title;
title = (status == kCLAuthorizationStatusDenied) ? #"Location services are off" : #"Background location is not enabled";
NSString *message = #"To use background location you must turn on 'Always' in the Location Services Settings";
UIAlertView *alertView = [[UIAlertView alloc] initWithTitle:title
message:message
delegate:self
cancelButtonTitle:#"Cancel"
otherButtonTitles:#"Settings", nil];
[alertView show];
}
// The user has not enabled any location services. Request background authorization.
else if (status == kCLAuthorizationStatusNotDetermined) {
[self.locationManager requestAlwaysAuthorization];
}
}
- (void)alertView:(UIAlertView *)alertView clickedButtonAtIndex:(NSInteger)buttonIndex
{
if (buttonIndex == 1) {
// Send the user to the Settings for this app
NSURL *settingsURL = [NSURL URLWithString:UIApplicationOpenSettingsURLString];
[[UIApplication sharedApplication] openURL:settingsURL];
}
}
Courtesy copy of this blog post