我已经在我的应用上实现了Face ID身份验证，并且用户在点击按钮时会获得身份验证。我还实现了一种注销用户的注销方法：
dismiss(animated: true, completion: {
UserDefaults.standard.set(false, forKey: "hasLoginKey")
})
但是，当我注销然后尝试重新登录时，系统不会提示我输入FaceID，而是跳过了它，并且我已完全登录。我的问题是如何防止这种情况发生，并在用户每次点击按钮时提示用户登录？
这是按钮代码：
@IBAction func loginButtonPressed(_ sender: Any) {
//Define Button variable from the button that has been tapped.
let button = sender as! UIButton
//If the button tag is Touch ID, authenticate the user
if(button.tag == loginWithTouchID)
{
//Check if device is compatible with Touch ID
if(touchMe.canEvaluatePolicy())
{
//Get Response from Touch ID popup
touchMe.authenticateUser() { responsCode in
if let responsCode = responsCode {
if(responsCode == 0)
{
//If Touch ID is not available
self.customAlert(title: "Error", message: "Touch ID not available")
}
else if(responsCode == 1)
{
//If Touch ID has not been setup
self.customAlert(title: "Error", message: "Touch ID may not be configured")
}
else if(responsCode == 2)
{
//If Touch ID authentication failed
self.customAlert(title: "Error", message: "There was a problem verifying your identity")
}
} else {
//If there is no response code, that means Touch ID was successful in authenticating user and we can now call the login method
Timer.scheduledTimer(timeInterval: 0.4, target: self, selector: #selector(Login.login), userInfo: nil, repeats: false)
}
}
}
}
else
{
Timer.scheduledTimer(timeInterval: 0.4, target: self, selector: #selector(Login.login), userInfo: nil, repeats: false)
}
}
和我的TouchIDAuth类
class TouchIDAuth {
let context = LAContext()
func canEvaluatePolicy() -> Bool {
return context.canEvaluatePolicy(.deviceOwnerAuthenticationWithBiometrics, error: nil)
}
func authenticateUser(completion: @escaping (NSNumber?) -> Void) {
guard canEvaluatePolicy() else {
completion(0)
return
}
context.evaluatePolicy(.deviceOwnerAuthenticationWithBiometrics, localizedReason: "Logging in with Touch ID") { (success, evaluateError) in
if success {
DispatchQueue.main.async {
completion(nil)
}
} else {
let response: NSNumber
switch evaluateError?._code {
case Int(kLAErrorAuthenticationFailed):
response = 2
case Int(kLAErrorUserCancel):
response = 3
case Int(kLAErrorUserFallback):
response = 4
default:
response = 1
}
completion(response)
}
}
}
}
这是在按下按钮的方法中调用的登录方法
@objc func login() {
//Start Activity Indicator
self.createIndicator()
//Define Username and Password Variables
var user: String!
var pass: String!
//Check if User is Authenticating with TouchID, we do this so we know to use credentials from Keychain to make the API call with
if(loginButton.tag == loginWithTouchID)
{
//If Yes, Get the username from Keychain
if let storedUsername = UserDefaults.standard.value(forKey: "username") as? String {
//Get Password from Keychain
do {
let passwordItem = KeychainPasswordItem(service: KeychainConfiguration.serviceName,
account: storedUsername,
accessGroup: KeychainConfiguration.accessGroup)
let keychainPassword = try passwordItem.readPassword()
//Store Username and Password from Keychain into Username and Password variables
user = storedUsername
pass = keychainPassword
}
catch {
//If something went wrong, stop the Activity Indicator and Alert the user something went wrong.
self.stopIndicator()
self.customAlert(title: "Error", message: "Error reading password from keychain - \(error)")
}
}
}
else
{
//If we are not using Touch ID, store the username and password text field into the username and password variable to use for the API Call
user = username.text!
pass = password.text!
}
//Finally call the webservice
WebService().loginUser(user, password: pass)
{
(result: Bool) in
//If API call is successful
if(result == true)
{
//Stop Activity Indicator
self.stopIndicator()
//Check if button tag is create, login or touch ID
if self.loginButton.tag == self.createLoginButtonTag {
//If create, check if a user has login
let hasLoginKey = UserDefaults.standard.bool(forKey: "hasLoginKey")
if !hasLoginKey {
//If not, add username to App Default
UserDefaults.standard.setValue(user, forKey: "username")
}
//Try and save the password to Keychain
do {
//Create a KeychainPasswordItem
let passwordItem = KeychainPasswordItem(service: KeychainConfiguration.serviceName, account: user!, accessGroup: KeychainConfiguration.accessGroup)
//Save password to the new KeychainPasswordItem
try passwordItem.savePassword(pass!)
//Add hasLoginKey bool to App Defaults
UserDefaults.standard.set(true, forKey: "hasLoginKey")
//Change Login button tag to Login as we do not need to create this user again
self.loginButton.tag = self.loginButtonTag
//Store Credentials to App Delegate to make API calls down the road.
self.appDelegate.username = user
self.appDelegate.password = pass
self.password.text = ""
//Everything has been authenticated, proceed to Dashboad
self.performSegue(withIdentifier: "toolbarSegue", sender: nil)
} catch {
//Something went wrong, alert the user with error.
self.customAlert(title: "Error", message: "Error updating keychain - \(error)")
}
}
//If Login Button tag with Login
else if self.loginButton.tag == self.loginButtonTag {
//Check if user exists in Keychain
if self.checkLogin(username: user, password: pass) {
//Store Credentials to App Delegate to make API calls down the road.
self.appDelegate.username = user
self.appDelegate.password = pass
self.password.text = ""
//Exisiting user has been authenticated, proceed to Dashboad
self.performSegue(withIdentifier: "toolbarSegue", sender: nil)
} else {
//User does not exist in Keychain, alert user there is an error.
self.customAlert(title: "Login Problem", message: "Sorry Login Failed, User and/or Passsword Incorrect")
}
}
//If Login Button tag with Touch ID
else if self.loginButton.tag == self.loginWithTouchID {
//Store Credentials to App Delegate to make API calls down the road.
self.appDelegate.username = user
self.appDelegate.password = pass
self.password.text = ""
//Touch ID has been authenticated, proceed to Dashboad
self.performSegue(withIdentifier: "toolbarSegue", sender: nil)
}
}
else
{
//Stop Activity Indicator
self.stopIndicator()
//API call was unsuccessful, alert user.
self.customAlert(title: "Login Problem", message: "Sorry Login Failed, User and/or Passsword Incorrect")
}
}
}
答案 0 :(得分：2)
我认为您正在const rectNode:any = this.createSvgElem('rect', {
'x': options.bbox[0],
'y': options.bbox[1],
'width': options.bbox[2] - options.bbox[0],
'height': options.bbox[3] - options.bbox[1],
'id': node.id,
'bbox': node.title,
'class': className
});
parentRectsNode.appendChild(rectNode);
// cross-link both nodes:
rectNode.linkedNode = node;
node.linkedNode = rectNode;
}
的这一行中跟踪登录按钮标记：
login这就是为什么当用户下次单击登录按钮时，它将直接对用户进行身份验证（因为条件是//Change Login button tag to Login as we do not need to create this user again, as you have specified
self.loginButton.tag = self.loginButtonTag
）：
false所以我认为您不应该更改 if(button.tag == loginWithTouchID) {
// login with touchID
else {
// authenticate the user
}
答案 1 :(得分：0)
注意：根据您的问题
但是，当我注销然后尝试重新登录时，系统不会提示我输入FaceID，而是跳过了它，并且我已完全登录。
通常，当您更新UserDefaults时（即针对键设置新值/对象），您确实添加了以下代码以使更改生效。
UserDefaults.standard.syncronize()
因此，请在
之后添加UserDefaults.standard.set(false, forKey: "hasLoginKey") // 1
UserDefaults.standard.setValue(user, forKey: "username") // 2
UserDefaults.standard.set(true, forKey: "hasLoginKey") // 3
希望有帮助。
答案 2 :(得分：0)
我还实现了一种注销用户的注销方法：
dismiss（动画：true，完成：{
UserDefaults.standard.set（false，forKey：“ hasLoginKey”）
}）
我的应用具有相同的行为。提示一次进行FaceID身份验证，而不是注销后提示。
如@Pranav Kasetti所述，在注销方法中添加TouchIDAuth.context = LAContext()（将其更改为var），如@Pranav Kasetti所述，身份验证上下文将重新初始化，并且将再次提示您的用户使用FaceID（或TouchID）。