 
 
     // MARK: - WKWebView delegate
+
+    func webView(webView: WKWebView, didStartProvisionalNavigation navigation: WKNavigation!) {
+        UIApplication.sharedApplication().networkActivityIndicatorVisible = true
+    }
+
+    func webView(webView: WKWebView, didFinishNavigation navigation: WKNavigation!) {
+        UIApplication.sharedApplication().networkActivityIndicatorVisible = false
+    }
 
     func webView(webView: WKWebView, decidePolicyForNavigationAction navigationAction: WKNavigationAction, decisionHandler: (WKNavigationActionPolicy) -> Void) {
 

        self.webview?.loadRequest(NSURLRequest(URL: NSURL(string: authUrlString as String)!))
    }


    // MARK: - Private methods



                    delegate?.foursquareAuthViewControllerDidSucceed(accessToken)

                    dismissViewControllerAnimated(true, completion: nil)

                    decisionHandler(WKNavigationActionPolicy.Cancel)
