我正在制作一个带有登录表单的 iOS 应用程序 (Obj-c)。我想弄清楚是否有办法使用 Touch ID 登录。这对我的应用程序来说将是一个了不起的功能，但我找不到实现它的方法。 在最近的 PayPal 更新中，它们包含了 Touch ID 登录 - 所以有一种方法可以做到这一点。

编辑:如果用户输入了正确的 Touch ID，我知道如何获取，但我不知道之后该怎么做。 如果用户输入他的用户名，然后正确添加 Touch ID 会怎样？我怎么知道这个用户有这个 Touch ID？

最佳答案

好的，首先创建一个像这样的 Action :

我们需要更多详细信息，因为我不知道您是指 Obj-C 还是 swift，我将两者都发布。

Obj-C

首先导入本地认证框架

#import <LocalAuthentication/LocalAuthentication.h>

然后我们创建一个 IBAction 并添加以下代码:

- (IBAction)authenticateButtonTapped:(id)sender {
   LAContext *context = [[LAContext alloc] init];

   NSError *error = nil;
   if ([context canEvaluatePolicy:LAPolicyDeviceOwnerAuthenticationWithBiometrics error:&error]) {
       [context evaluatePolicy:LAPolicyDeviceOwnerAuthenticationWithBiometrics
               localizedReason:@"Are you the device owner?"
                         reply:^(BOOL success, NSError *error) {

           if (error) {
               UIAlertView *alert = [[UIAlertView alloc] initWithTitle:@"Error"
                                                               message:@"There was a problem verifying your identity."
                                                              delegate:nil
                                                     cancelButtonTitle:@"Ok"
                                                     otherButtonTitles:nil];
               [alert show];
               return;
           }

           if (success) {
               UIAlertView *alert = [[UIAlertView alloc] initWithTitle:@"Success"
                                                               message:@"You are the device owner!"
                                                              delegate:nil
                                                     cancelButtonTitle:@"Ok"
                                                     otherButtonTitles:nil];
               [alert show];

           } else {
               UIAlertView *alert = [[UIAlertView alloc] initWithTitle:@"Error"
                                                               message:@"You are not the device owner."
                                                              delegate:nil
                                                     cancelButtonTitle:@"Ok"
                                                     otherButtonTitles:nil];
               [alert show];
           }

       }];

   } else {

       UIAlertView *alert = [[UIAlertView alloc] initWithTitle:@"Error"
                                                       message:@"Your device cannot authenticate using TouchID."
                                                      delegate:nil
                                             cancelButtonTitle:@"Ok"
                                             otherButtonTitles:nil];
       [alert show];

   }
}

只需将您的 IBAction 连接到一个将提示身份验证的按钮。

但是在 Swift 中你会使用:

将以下框架添加到您的项目中:LocalAuthentication 然后将其导入到您的 swift 文件中:

import LocalAuthentication

然后创建以下方法，提示您使用 touch id:

func authenticateUser() {
        // Get the local authentication context.
        let context = LAContext()

        // Declare a NSError variable.
        var error: NSError?

        // Set the reason string that will appear on the authentication alert.
        var reasonString = "Authentication is needed to access your notes."

        // Check if the device can evaluate the policy.
        if context.canEvaluatePolicy(LAPolicy.DeviceOwnerAuthenticationWithBiometrics, error: &error) {
            [context .evaluatePolicy(LAPolicy.DeviceOwnerAuthenticationWithBiometrics, localizedReason: reasonString, reply: { (success: Bool, evalPolicyError: NSError?) -> Void in

                if success {

                }
                else{
                    // If authentication failed then show a message to the console with a short description.
                    // In case that the error is a user fallback, then show the password alert view.
                    println(evalPolicyError?.localizedDescription)

                    switch evalPolicyError!.code {

                    case LAError.SystemCancel.rawValue():
                        println("Authentication was cancelled by the system")

                    case LAError.UserCancel.rawValue():
                        println("Authentication was cancelled by the user")

                    case LAError.UserFallback.rawValue():
                        println("User selected to enter custom password")
                        self.showPasswordAlert()

                    default:
                        println("Authentication failed")
                        self.showPasswordAlert()
                    }
                }

            })]
        }
        else{
            // If the security policy cannot be evaluated then show a short message depending on the error.
            switch error!.code{

            case LAError.TouchIDNotEnrolled.rawValue():
                println("TouchID is not enrolled")

            case LAError.PasscodeNotSet.rawValue():
                println("A passcode has not been set")

            default:
                // The LAError.TouchIDNotAvailable case.
                println("TouchID not available")
            }

            // Optionally the error description can be displayed on the console.
            println(error?.localizedDescription)

            // Show the custom alert view to allow users to enter the password.
            self.showPasswordAlert()
        }
    }

最后从 func viewDidLoad 调用函数，如下所示:authenticateUser()

希望对您有所帮助。继续编码。

资料来源: 迅速: App Coda iOS 8 Touch ID Api

objective-C : tutPlus iOS Touch ID

感谢 Matt Logan 更新了 swift 代码。

关于ios - 用于登录 iOS 的 Touch ID，我们在Stack Overflow上找到一个类似的问题： https://stackoverflow.com/questions/30594516/