用户取消了 touchID 实现错误答案

【问题标题】：touchID implementation error cancelled by user用户取消了 touchID 实现错误
【发布时间】：2020-01-18 14:44:50
【问题描述】：

如何解决 TouchId 错误：Domain=com.apple.LocalAuthentication Code=-2 "Canceled by user."

我再次尝试添加本地上下文：

let myContext = LAContext()
let myLocalizedReasonString = "Please use your last login for Inspyrus Supplier Central."        

var authError: NSError?
if #available(iOS 8.0, macOS 10.12.1, *) {
    if myContext.canEvaluatePolicy(.deviceOwnerAuthenticationWithBiometrics, error: &authError) {
        myContext.evaluatePolicy(.deviceOwnerAuthenticationWithBiometrics, localizedReason: myLocalizedReasonString) { success, evaluateError in
            DispatchQueue.main.async {
                if success {
                    self.btnLoginClicked(UIButton())
                } else {
                    print(evaluateError?.localizedDescription ?? "Failed to authenticate")
                    // Fall back to a asking for username and password.
                    // ...
                }
            }
        }
    }
}

【问题讨论】：

标签： ios swift biometrics touch-id localauthentication

【解决方案1】：

您可以检查从evaluatePolicy 调用返回的evaluateError 是否为LAError.userCancel。

类似这样的：

if success {
    //...
}
else if let authError = evaluateError as? LAError {
    switch authError.code {
    case .userCancel:
        // Authentication was canceled by user (e.g. tapped Cancel button).
        break
    default:
        // Other error
        break
    }

    // Or
    switch authError {
    case LAError.userCancel:
        // Authentication was canceled by user (e.g. tapped Cancel button).
        break
    default:
        // Other error
        break
    }
}

【讨论】：