Use of unresolved identifier 'handled'エラーについて

Question

swift4
xcode9.1

iosアプリにgoogle認証を実装する動画を参考にしています。
まだコードを自ら書けるレベルでは無いので動画作成者さんのコードをとにかく追って真似ていますが、

Use of unresolved identifier 'handled'のエラーが出ます。
（ 場所は●return handled●の所です）

恥ずかしながらこれら組み込んだコードの成り立ちを把握できていない為、エラー原因が分かりません。
このAppDelegateで不備のある箇所を教えていただきたいです。
また、return hundredは特にどんなメソッドで使うのでしょうか？
お願いします。

import UIKit
import Firebase
import FirebaseAuth
import GoogleSignIn


@UIApplicationMain
class AppDelegate: UIResponder, UIApplicationDelegate, GIDSignInDelegate {
            
    var window: UIWindow?
    
    func application(_ application: UIApplication, didFinishLaunchingWithOptions launchOptions: [UIApplicationLaunchOptionsKey: Any]?) -> Bool {
                // Override point for customization after application launch.
                FirebaseApp.configure()
                
                GIDSignIn.sharedInstance().clientID = FirebaseApp.app()?.options.clientID
                GIDSignIn.sharedInstance().delegate = self
                
                return true
    }
            
    func applicationWillResignActive(_ application: UIApplication) {
                // Sent when the application is about to move from active to inactive state. This can occur for certain types of temporary interruptions (such as an incoming phone call or SMS message) or when the user quits the application and it begins the transition to the background state.
                // Use this method to pause ongoing tasks, disable timers, and invalidate graphics rendering callbacks. Games should use this method to pause the game.
    }
            
            func applicationDidEnterBackground(_ application: UIApplication) {
                // Use this method to release shared resources, save user data, invalidate timers, and store enough application state information to restore your application to its current state in case it is terminated later.
                // If your application supports background execution, this method is called instead of applicationWillTerminate: when the user quits.
    }
            
            func applicationWillEnterForeground(_ application: UIApplication) {
                // Called as part of the transition from the background to the active state; here you can undo many of the changes made on entering the background.
    }
            
            func applicationDidBecomeActive(_ application: UIApplication) {
                // Restart any tasks that were paused (or not yet started) while the application was inactive. If the application was previously in the background, optionally refresh the user interface.
    }
            
            func applicationWillTerminate(_ application: UIApplication) {
                // Called when the application is about to terminate. Save data if appropriate. See also applicationDidEnterBackground:.
    }
  
    func application(_ app: UIApplication, open url: URL, options:
        [UIApplicationOpenURLOptionsKey : Any] = [:]) -> Bool {
        GIDSignIn.sharedInstance().handle(url, sourceApplication:options[UIApplicationOpenURLOptionsKey.sourceApplication] as? String!, annotation: options[UIApplicationOpenURLOptionsKey.annotation])
    
         return handled
    }
    func sign(_ signIn: GIDSignIn!, didSignInFor user: GIDGoogleUser!, withError error: Error?) {
        // ...
        if let error = error {
           print(error.localizedDescription)
            return
    }
        print("Google Login Successful")
        
        guard let authentication = user.authentication else { return }
        let credential = GoogleAuthProvider.credential(withIDToken: authentication.idToken,
         accessToken: authentication.accessToken)
        
        Auth.auth().signIn(with: credential, completion: { (user, error) in
            if let error = error{
                print(error.localizedDescription)
                return
    }
            print("Successfully logged into Firebase")
    })
    }

    func sign(_  signIn: GIDSignIn!, didDisconnectWith user: GIDGoogleUser!, withError error: Error!) {
    //
    }
    
   
}

Answer 1

変数は宣言しないと使えません。
他の質問をみると苦戦してるようですが頑張ってください。

let handled = GIDSignIn.sharedInstance().handle(url, sourceApplication:options[UIApplicationOpenURLOptionsKey.sourceApplication] as? String!, annotation: options[UIApplicationOpenURLOptionsKey.annotation])

return handled

または

return GIDSignIn.sharedInstance().handle(url, sourceApplication:options[UIApplicationOpenURLOptionsKey.sourceApplication] as? String!, annotation: options[UIApplicationOpenURLOptionsKey.annotation])

Comments

[退会済みユーザー]

fromageblanc様　何度もご回答感謝します。
変数を注意して見ます。
前者のコードをreturn handled上に組み込むとエラーが消えました！ありがとうございます。
気になったのですが、このすぐ上に　GIDSignIn.sharedInstance() ...から続くコードと記述が同じですが重複してるのでしょうか？

[fromageblanc]

GIDSignIn.sharedInstance... を、let handled = GIDSignIn.sharedInstanceに変更するんですよ。追加じゃなくて。

[退会済みユーザー]

理解しました。
ありがとうございます！