没有Xcode，后台提取永远不会触发

Question

当我使用Xcode的背景提取模拟时，背景提取有效。但是，当设备未连接到Xcode时，后台提取不会进行大约几个小时的测试。

我启用了功能，我的应用未终止。有什么建议吗？

func application(_ application: UIApplication, didFinishLaunchingWithOptions launchOptions: [UIApplication.LaunchOptionsKey: Any]?) -> Bool {
    UIApplication.shared.setMinimumBackgroundFetchInterval(UIApplication.backgroundFetchIntervalMinimum)
    return true
}


func application(_ application: UIApplication, performFetchWithCompletionHandler completionHandler: @escaping (UIBackgroundFetchResult) -> Void) {

    let request = WeatherRequest(url: weatherUrl(for: "city"))
    request.perform{result in
        // show data in view controller
        completionHandler(.newData)
    }
}