我看到了一些其他问题,但我无法使其正常工作。我有一个用 swift 编码的 Mac 应用程序,它有一个 Firebase 登录,但用户输入一个存储在 Firebase 上的 key ,有没有办法在用户成功使用该 key 后自动删除该 key ?
这是我的数据库。
这是当前使用的代码。
import Cocoa
import FirebaseAuth
import FirebaseDatabase
class LoginViewController: NSViewController {
@IBOutlet weak var textUsername: NSTextField!
@IBOutlet weak var textPassword: NSSecureTextFieldCell!
@IBOutlet weak var btnLogin: NSButton!
var keyArray = \[Int64\]()
override func viewDidLoad() {
super.viewDidLoad()
}
override func viewWillAppear() {
}
func getLoginState() -> Bool{
let state = UserDefaults.standard.bool(forKey: "isRegistered")
if (state) {
return true
} else {
return false
}
}
override func viewDidAppear() {
let state = self.getLoginState()
if (state){
self.performSegue(withIdentifier: NSStoryboardSegue.Identifier(rawValue: "loginsegue"), sender: nil)
self.view.window?.close()
}
var ref: DatabaseReference!
ref = Database.database().reference()
let keyRef = ref.child("key1")
keyRef.observe(DataEventType.childAdded, with: { (snapshot) in
// let postDict = snapshot.value as? \[String : AnyObject\] ?? \[:\]
let keyStr = snapshot.value as? Int64
if let actualPost = keyStr{
self.keyArray.append(actualPost)
}
})
}
@IBAction override func dismissViewController(_ viewController: NSViewController) {
dismiss(self)
}
@IBAction func close(sender: AnyObject) {
self.view.window?.close()
}
@IBAction func onSignup(_ sender: Any) {
// self.performSegue(withIdentifier: NSStoryboardSegue.Identifier(rawValue: "gotosignup"), sender: sender)
// self.view.window?.close()
}
func dialogOK(question: String, text: String) -> Void {
let alert: NSAlert = NSAlert()
alert.messageText = question
alert.informativeText = text
alert.alertStyle = NSAlert.Style.warning
alert.addButton(withTitle: "OK")
alert.runModal()
}
@IBAction func onLogin(_ sender: Any) {
//self.btnLogin.isEnabled = false
var isKey = false
if (!self.textUsername.stringValue.isEmpty) {
for key in keyArray{
if(Int64(self.textUsername.stringValue)! == key)
{
UserDefaults.standard.set(true, forKey:"isRegistered")
self.performSegue(withIdentifier: NSStoryboardSegue.Identifier(rawValue: "loginsegue"), sender: nil)
self.view.window?.close()
isKey = true
}
}
if (!isKey){
self.dialogOK(question: "Error", text: "Invalid Key")
}
} else {
self.dialogOK(question: "Error", text: "Please Input Key")
}
}
}
最佳答案
你不能像这样对数据库进行排序并期望有一个有效的代码,即使有任何代码。它会产生困惑的代码:
You need to:
- Sort your database like [1220:0]. the key first. 0 & 1 as an indicator if it's used or not.
- Once the user taps
onLogin()
you need to set the used key value to 1- Setup Cloud Functions to check if the used key is equal to 1, if yes. then remove the key.
Do the rest of the work.
帮助您入门的相关文章:
关于swift - 自动从 Firebase 数据库中删除数据,我们在Stack Overflow上找到一个类似的问题: https://stackoverflow.com/questions/52789548/