Ios TouchID：如何获取TouchID身份验证尝试？

我需要实现触摸ID，并且必须向用户显示关于剩余身份验证尝试的警报。下面是我使用的代码

在一次错误的身份验证尝试后，未调用应答块。它在3之后被调用，继续错误的身份验证尝试。是否有任何方法可以获得错误身份验证尝试的计数

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

NSError *authError = nil;
NSString *myLocalizedReasonString = @"Touch ID Test to show Touch ID working in a custom app";

if ([myContext canEvaluatePolicy:LAPolicyDeviceOwnerAuthenticationWithBiometrics error:&authError]) {
    [myContext evaluatePolicy:LAPolicyDeviceOwnerAuthenticationWithBiometrics
              localizedReason:myLocalizedReasonString
                        reply:^(BOOL success, NSError *error) {
                            if (success) {
                                dispatch_async(dispatch_get_main_queue(), ^{
                                    [self performSegueWithIdentifier:@"Success" sender:nil];
                                });
                            } else {
                                dispatch_async(dispatch_get_main_queue(), ^{
                                    UIAlertView *alertView = [[UIAlertView alloc] initWithTitle:@"Error"
                                                                                        message:error.description
                                                                                       delegate:self
                                                                              cancelButtonTitle:@"OK"
                                                                              otherButtonTitles:nil, nil];
                                    [alertView show];
                                    NSLog(@"Switch to fall back authentication - ie, display a keypad or password entry box");
                                });
                            }
                        }];
} else {
    dispatch_async(dispatch_get_main_queue(), ^{
        UIAlertView *alertView = [[UIAlertView alloc] initWithTitle:@"Error"
                                                            message:authError.description
                                                           delegate:self
                                                  cancelButtonTitle:@"OK"
                                                  otherButtonTitles:nil, nil];
        [alertView show];
    });
}

---

我浏览了文档，不可能在每次失败的尝试中显示警报。只需参考文档即可 .

您可以在不同的错误情况下显示警报。第三次失败尝试后LAError。将调用authenticationFailed，第五次失败尝试后LAError。将调用touchIDLockout。您可以在此处显示警报。有关更多信息，请参阅