Detecting if there is data transfer in iOS app with Swift - ios

Question

I was wanting to know if anyone knows how to detect if there is data transfer or not within an iOS app. I am using a Swift Reachability library to detect if there is wifi or cellular connection, but this does not let me know if there is actual data being transferred.
My app starts out with a WKWebView, and in the case there is no data being transferred to load the webview that takes up the entire screen, I would like to present an alertController to the user.
Reachability lets me know if there is a connection to wifi or a cellular network, but they don't help with letting me know if there is any data being transferred. I'm testing with my wifi on, but with no network connection, and I'm unable to present any alertController as connection is always passing true for isReachable().
Does anyone know how to go about this? Thank you.

Answer 1

Alamofire Provide the functionaly to check the network status. So here it is in detail with some other functionality.
I have created an APIClient Manager class in my project.
import UIKit
import Alamofire
import AlamofireNetworkActivityIndicator
// Completion handeler
typealias TSAPIClientCompletionBlock = (response: NSHTTPURLResponse?, result: AnyObject?, error: NSError?) -> Void
// MARK: -
class TSAPIClient: Manager {
// MARK: - Properties methods
private let manager = NetworkReachabilityManager(host: "www.apple.com") // could be any website, Just to check connectivity
private var serviceURL: NSURL?
// MARK: - init & deinit methods
init(baseURL: NSURL,
configuration: NSURLSessionConfiguration = NSURLSessionConfiguration.defaultSessionConfiguration(),
delegate: SessionDelegate = SessionDelegate(),
serverTrustPolicyManager: ServerTrustPolicyManager? = nil) {
super.init(configuration: configuration, delegate: delegate, serverTrustPolicyManager: serverTrustPolicyManager)
var aURL = baseURL
// Ensure terminal slash for baseURL path, so that NSURL relativeToURL works as expected
if aURL.path?.characters.count > 0 && !aURL.absoluteString.hasSuffix("/") {
aURL = baseURL.URLByAppendingPathComponent("")
}
serviceURL = baseURL
NetworkActivityIndicatorManager.sharedManager.isEnabled = true
observeNetworkStatus()
}
// MARK: - Public methods
func serverRequest(methodName: String, parameters: [String : AnyObject]? , isPostRequest: Bool, headers: [String : String]?, completionBlock: TSAPIClientCompletionBlock) -> Request {
let url = NSURL(string: methodName, relativeToURL: serviceURL)
print("\(url)")
let request = self.request(isPostRequest ? .POST : .GET, url!, parameters: parameters, encoding: isPostRequest ? .JSON : .URL, headers: headers)
.validate(statusCode: 200..<600)
.responseJSON { response in
switch response.result {
case .Success:
completionBlock(response: response.response, result: response.result.value, error: nil
)
break
case .Failure(let error):
completionBlock(response: response.response, result: nil, error: error)
break
}
}
return request
}
func cancelAllRequests() {
session.getAllTasksWithCompletionHandler { tasks in
for task in tasks {
task.cancel()
}
}
}
// this will contiously observe network changes
func observeNetworkStatus() {
manager?.listener = { status in
print("Network Status Changed: \(status)")
if status == .NotReachable {
} else if status == .Unknown {
} else {
// status is reachable
// posting a notification for network connectivity NSNotificationCenter.defaultCenter().postNotificationName(kNetworkStatusConnectedNotification, object: nil)
}
}
manager?.startListening()
}
// If you want to check network manually for Example before pushing a viewController.
func isNetworkReachable() -> Bool {
return manager?.isReachable ?? false
}
}
kNetworkStatusConnectedNotification is a constant declared as following
let kNetworkStatusConnectedNotification = "kNetworkStatusConnectedNotification"
Now, Where you want to observe the network changes in your application, register the notification in that viewController as follows
NSNotificationCenter.defaultCenter().addObserver(self, selector: #selector(HomeViewController.applicationIsConnectedToNetwok), name: kNetworkStatusConnectedNotification, object: nil)
and in the selector do whatever you want to do when you get network connectivity
func applicationIsConnectedToNetwok() {
// e.g LoadData
}
I have written this method in my Session class and I am using it to check connectivity mannualy
func isNetworkReachable() -> Bool {
return YourAPIClient.sharedClient.isNetworkReachable()
}
I have added some comments in the code for your understanding. I hope it helps.