OK, so I have had this problem before and solved it unknowingly and now it is reoccurring!
"error:
Error Domain=ALAssetsLibraryErrorDomain Code=-3312 "Global denied access" UserInfo=0x169aa0
{NSLocalizedFailureReason=The user has denied all applications access to their media.,
NSLocalizedRecoverySuggestion=This setting can be changed in Preferences.,
NSLocalizedDescription=Global denied access}"
Please NOTE://I do not get this issue in the simulator - my code for iterating assets works perfectly on the simulator.
Surely this is an easy fix but be damned if I can find anything under 'Preferences' anywhere that assists.
Please halp!
What a joke - Location services must be turned on...
What a JOKE!
Simply go to Settings>General>Reset>Reset Location Warnings.
However this won't help your users out but it is useful for development
For iOS 4.2 and later use CLLocationManager authorizationStatus class method.
it will return a CLAuthorizationStatus enum ( declared at CLLocationManager.h ), you can test the return for kCLAuthorizationStatusAuthorized.
if ( [CLLocationManager authorizationStatus] == kCLAuthorizationStatusAuthorized ) {
// do your stuff
} else {
// sorry user, you must enable us to see your location if you want to use YOURS assets library
}
iOS 6 introduce this method for ALAssetsLibrary class also.
来源：https://stackoverflow.com/questions/3561321/iphone-how-to-enable-application-access-to-media-on-the-device-alassetslibr