如何避免swift 3中的错误无效重新声明？ [复制]答案

【问题标题】：How to avoid the error invalid redeclaration in swift 3? [duplicate]如何避免swift 3中的错误无效重新声明？ [复制]
【发布时间】：2018-05-07 04:45:05
【问题描述】：

在这里我已经集成了 Braintree PayPal 和 google 登录集成，然后我在应用程序委托类中实现了代码，但是两个代码具有相同的功能并显示错误 Invalid redeclaration of 'application(_:open:options:)' 任何人都可以帮助我如何避免这种情况？

这是我的代码

import UIKit
import Braintree
import GoogleSignIn
//import GoogleMaps

@UIApplicationMain
class AppDelegate: UIResponder, UIApplicationDelegate,GIDSignInDelegate {

    var window: UIWindow?

    func application(_ application: UIApplication, didFinishLaunchingWithOptions launchOptions: [UIApplicationLaunchOptionsKey: Any]?) -> Bool {
        BTAppSwitch.setReturnURLScheme("com.ewallsolutions.basic.Gometoo.payments")
        IQKeyboardManager.shared.enable = true
        GIDSignIn.sharedInstance().delegate = self
        return true
    }
    func application(_ app: UIApplication, open url: URL, options: [UIApplicationOpenURLOptionsKey : Any]) -> Bool {
        if url.scheme?.localizedCaseInsensitiveCompare("com.ewallsolutions.basic.Gometoo.payments") == .orderedSame {
            return BTAppSwitch.handleOpen(url, options: options)
        }
        return false
    }

    @available(iOS 9.0, *)
    func application(_ application: UIApplication, open url: URL, options: [UIApplicationOpenURLOptionsKey : Any]) -> Bool {
            return GIDSignIn.sharedInstance().handleURL(url,
                                                        sourceApplication:options[UIApplicationOpenURLOptionsKey.sourceApplication] as? String,
                                                        annotation: [:])
    }

    func sign(_ signIn: GIDSignIn!, didSignInFor user: GIDGoogleUser!, withError error: Error!) {
        if (error == nil) {
            // Perform any operations on signed in user here.
            let userId = user.userID                  // For client-side use only!
            let idToken = user.authentication.idToken // Safe to send to the server
            let name = user.profile.name
            let email = user.profile.email
            let userImageURL = user.profile.imageURL(withDimension: 200)

        }
        else
        {
            print("\(error.localizedDescription)")
        }
    }

    func signIn(signIn: GIDSignIn!, didDisconnectWithUser user:GIDGoogleUser!,
                withError error: NSError!)
    {
        print("user disconnected")
        // Perform any operations when the user disconnects from app here.
        // ...
    }

【问题讨论】：

见这个例如：stackoverflow.com/questions/35510410/…\

标签： ios swift

【解决方案1】：

你不能把同一个方法写两次。所以，你可以这样写。

func application(_ application: UIApplication, open url: URL, options: [UIApplicationOpenURLOptionsKey : Any]) -> Bool {
        let braintreeHandle = false
        if url.scheme?.localizedCaseInsensitiveCompare("com.ewallsolutions.basic.Gometoo.payments") == .orderedSame {
            braintreeHandle = BTAppSwitch.handleOpen(url, options: options)
        }

        let googleHandle = GIDSignIn.sharedInstance().handleURL(url,
                                                                sourceApplication:options[UIApplicationOpenURLOptionsKey.sourceApplication] as? String,
                                                                annotation: [:])
        return braintreeHandle || googleHandle
    }

【讨论】：

【解决方案2】：

您收到此错误是因为您使用了两次打开 url 方法。删除一种方法并使用以下代码来避免此错误：

 func application(_ application: UIApplication, open url: URL, options: [UIApplicationOpenURLOptionsKey : Any]) -> Bool {

        if url.scheme?.localizedCaseInsensitiveCompare("com.ewallsolutions.basic.Gometoo.payments") == .orderedSame {
            return BTAppSwitch.handleOpen(url, options: options)

        } else {

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

【讨论】：