- (void)evaluatePolicy

{

    LAContext *context = [[LAContext alloc] init];

    __block  NSString *msg;

     

    // show the authentication UI with our reason string

    [context evaluatePolicy:LAPolicyDeviceOwnerAuthenticationWithBiometrics localizedReason:NSLocalizedString(@"UNLOCK_ACCESS_TO_LOCKED_FATURE", nil) reply:

     ^(BOOL success, NSError *authenticationError) {

         if (success) {

             msg =[NSString stringWithFormat:NSLocalizedString(@"EVALUATE_POLICY_SUCCESS", nil)];

         } else {

             msg = [NSString stringWithFormat:NSLocalizedString(@"EVALUATE_POLICY_WITH_ERROR", nil), authenticationError.localizedDescription];

         }

         [self printResult:self.textView message:msg];

     }];

     

}