[weak self]

SelfServiceViewController.swift

func startLoad() {
        ReachabilityManager.performOperationOnceReachable("SelfServiceViewController", onConnectionBlock: {
            let rkObjectManager = RKObjectManager.sharedManager()
            
            let dndFetchOperation = AFJSONRequestOperation(request: rkObjectManager.HTTPClient.requestWithMethod("GET", path: "users/\(AppPreferences.userId())/extensions/b77bb090-2fde-11e5-80c4-56847afe9799", parameters: nil))
            let devicesFetchOperation = rkObjectManager.appropriateObjectRequestOperationWithObject(nil, method: .GET, path: "users/\(AppPreferences.userId())/devices", parameters: ["limit": 1000]) as! RKObjectRequestOperation
            rkObjectManager.enqueueBatchOfObjectRequestOperations([devicesFetchOperation, dndFetchOperation], progress: nil, completion: { [weak self] operations -> Void in
                let hasError = devicesFetchOperation.error != nil || dndFetchOperation.error != nil
                if hasError {
                    if !devicesFetchOperation.cancelled && !dndFetchOperation.cancelled {
                        return
                    }
                    self?.showFetchErrorMessage()
                } else {
                    let dndJSON = dndFetchOperation.responseJSON as? [String: AnyObject]
                    if let config = dndJSON?["config"] as? [String: AnyObject] {
                        if let simple = config["simple"] as? [String: AnyObject] {
                            let start = simple["start"] as? String
                            let end = simple["end"] as? String
                            self?.beginCellView.textField.text = UTCHelper.UTCToLocal(start)
                            self?.endCellView.textField.text = UTCHelper.UTCToLocal(end)
                            self?.serverStartDNDTime = start
                            self?.serverEndDNDTime = end
                            self?.dndEnabled = self?.serverStartDNDTime != nil && self?.serverEndDNDTime != nil
                            self?.toggleDoNotDisturbView((self?.toggleDndButton)!)
                        }
                    }
                    
                    self?.userDevices = devicesFetchOperation.mappingResult.array() as? [UserDevice]
                    self?.setInitialValues()
                    UIView.animateWithDuration(0.3, animations: {
                        if self?.loadingView != nil {
                            self?.loadingView.alpha = 0.0
                            self?.mainScrollView.alpha = 1.0
                        }
                        }, completion: {
                            finished in
                            if self?.loadingView != nil {
                                self?.loadingView.removeFromSuperview()
                            }
                            self?.mainScrollView.hidden = false
                    })
                }
            })
        })
    }