Question

我正在使用单例来从Firebase远程配置文件中获取参数。第一次运行应用程序时，我只能访问单例中的默认值;后续运行正确返回配置的值。什么是更好的方法，所以我可以从一个新的开始访问值？

protocol RemoteConfigProtocol {
    func remoteConfigReceived()
}

class RemoteConfigManager {

    static let sharedInstance = RemoteConfigManager()
    var delegate: RemoteConfigProtocol?

    let demoTitle: String

    // private initialiser for the singleton
    private init() {
        // Configure for dev mode, if needed
        let remoteConfig = RemoteConfig.remoteConfig()
        #if DEBUG
            let expirationDuration: TimeInterval = 0
            remoteConfig.configSettings = RemoteConfigSettings(developerModeEnabled: true)!
        #else
            let expirationDuration: TimeInterval = 3600
        #endif

        // default values
        let appDefaults: [String: NSObject] = [
            "demo_title": "Default Title" as NSObject
        ]
        remoteConfig.setDefaults(appDefaults)

        // what exactly does "activeFetched" do, then?
        remoteConfig.activateFetched()

        // set the values
        self.demoTitle = remoteConfig["demo_title"].stringValue!

        // this seems to prep app for subsequent launches
        remoteConfig.fetch(withExpirationDuration: expirationDuration) { status, _ in
            print("Fetch completed with status:", status, "(\(status.rawValue))")
            self.delegate?.remoteConfigReceived()
        }
    }
}

当异步fetch命令在上面的代码中返回时（可能是参数值），我仍然无法访问来自配置文件的这些值。只有在应用程序的后续运行中，它们才会存在。这是为什么？我在代码中遗漏了什么吗？

Answer 1

在获取完成后，您需要调用activateFetched（）。现在，你在之前调用它甚至开始提取。在您调用activateFetched（）之前，您的应用程序将无法使用提取的配置参数。

Answer 2

使用@ doug-stevenson的回答，这是获取配置参数的代码，并立即使用它们：

protocol RemoteConfigProtocol {
    func remoteConfigReceived()
}

class RemoteConfigManager {

    static let sharedInstance = RemoteConfigManager()
    var delegate: RemoteConfigProtocol?

    var demoTitle: String

    // private initialiser for the singleton
    private init() {
        // Configure for dev mode, if needed
        let remoteConfig = RemoteConfig.remoteConfig()
        #if DEBUG
            let expirationDuration: TimeInterval = 0
            remoteConfig.configSettings = RemoteConfigSettings(developerModeEnabled: true)!
        #else
            let expirationDuration: TimeInterval = 3600
        #endif

        // default values
        let appDefaults: [String: NSObject] = [
            "demo_title": "Default Title" as NSObject
        ]
        remoteConfig.setDefaults(appDefaults)

        // set the values from the defaults
        self.demoTitle = remoteConfig["demo_title"].stringValue!

        // fetch the new values
        remoteConfig.fetch(withExpirationDuration: expirationDuration) { status, _ in
            print("Fetch completed with status:", status, "(\(status.rawValue))")

            // activate the newly fetched values
            remoteConfig. activateFetched()

            // reset my variables
            self.demoTitle = remoteConfig["demo_title"].stringValue!

            // tell my view controller to update the UI
            self.delegate?.remoteConfigReceived()
        }
    }
}

Firebase远程配置会在初始请求时生成

2 个答案: