ios - authorizationStatus 返回一个 bool 值

Question

我不确定这是否可能。

当我调用 UNUserNotificationCenter.current().getNotificationSettings()

时，我希望从 authorizationStatus 返回一个 bool 值

我首先创建了一个回调 block 来确定 authorizationStatus 然后下一个函数将返回一个 bool 返回给原始调用者。

我像往常一样在 void 函数中遇到非 void 返回值，因为我的回调返回 void。

理想情况下，我想使用 checkNotificationBlocks() 就像方法一样:isNotificationEnabled()

func checkNotificationBlocks(callback: @escaping (Bool) -> Void)
{
    UNUserNotificationCenter.current().getNotificationSettings()
        {
            settings in
            var status = false
            switch settings.authorizationStatus
            {
            case .authorized: status = true
            case .denied: status = false
            case .notDetermined: status = false
            }

            if UIApplication.shared.isRegisteredForRemoteNotifications && status == true
            {callback(true) }
            else { callback(false) }
    }

}

func isNotificationEnabledBlocks() -> Bool
{
    checkNotificationBlocks {
        b in
        if b == true { return true } //Unexpected non-void return value in void function
        else { return false } //Unexpected non-void return value in void function
    }
}
//currentUserNotificationSettings' was deprecated in iOS 10.0:
func isNotificationEnabled() -> Bool 
{
      if UIApplication.shared.isRegisteredForRemoteNotifications && settings.types.rawValue != 0
        { print("isNotificationEnabled return true"); return true }
        else { print("isNotificationEnabled return false");return false }
    }

Answer 1

我最终确实更新了我的代码以获得我想要的结果。信号量在进行等待调用时获得锁定，并在从异步 block 发出信号时释放。

 func isNotificationEnabledBlocks() -> Bool
{
    let waitOut = DispatchSemaphore(value: 0)
    var checks = false

    checkNotificationBlocks {
        b in checks = b
        waitOut.signal()
    }
    waitOut.wait()
    return UIApplication.shared.isRegisteredForRemoteNotifications && checks == true ? true : false
}