iOS的Google firebase Auth文档中是否有错误？ 当我尝试代码时，这些是错误

Question

I am developing a ios app and tried connecting it to firebase and use its user auth function I am encountering several errors and I would also request you ppl to review my code. I trying very hard but nothing is solving these errors. Pls help

I tried searching any updates in code and any answers to the error but unfortunately, I got nothing. I am using Xcode 11 beta and coding for iOS 12.2

override func viewWillAppear(_ animated: Bool) {
    super.viewWillAppear(animated)
    // [START auth_listener]
    var handle = Auth.auth().addStateDidChangeListener { (auth, user) in
      // [START_EXCLUDE]
      self.setTitleDisplay(user) //Error "Value of type 'ViewController' has no member 'setTitleDisplay'"
      self.tableView.reloadData() //Error "Value of type 'ViewController' has no member 'tableView'"



guard let strongSelf = self else { return } //Error "Initializer for conditional binding must have Optional type, not 'ViewController" 
        // [START_EXCLUDE]
        strongSelf.hideSpinner {
          if let error = error {
            strongSelf.showMessagePrompt(error.localizedDescription)
            return
          }
          strongSelf.navigationController?.popViewController(animated: true)
        }
        // [END_EXCLUDE]
      }

I expect the code to sign in an already existing user for firebase

Answer 1

The documentation is accurate but what's in the getting started guide are just snippets of code.

You will need to take a look at the actual full code example to get the 'big picture'. For example, this line

Auth.auth().removeStateDidChangeListener(handle!)

is being flagged as you've not defined a class var of handle. What's shown in the getting started guide is a snippet.

You should click on the blue link (I circled in red) that take you to the actual full code example. When you do that, you'll see handle is defined as a class var

var handle: AuthStateDidChangeListenerHandle?

I think if you'll work through the actual full code example, those errors will go away.