Highlights from my first pure swift iOS app - Swiflytics!

I needed an app to look at live analytics of my website/app but did not find a good app on AppStore. Swiflytics is super simple tiny app completely written in swift. Here is a video overview:

Get it on AppStore

Source code and build instructions are available at github.

Here is some of the code from app which I want to highlight :

No more ugly dispatch_async snake case

onMainThread { completion(onlineUsers) }

Some of the async code look totally elegant

fetchTotalOnlineUsers {
    self.activeUsersLabel.text = $0
}

fetchData {
    self.tableView.reloadData()
}

guards for easy validation code!

@IBAction func saveButtonPressed(sender: AnyObject?) {
  guard let cardName = self.cardNameField.text where cardName.characters.count > 0 else {
    showAlertWithText("Enter name of the card", onViewController: self)
    return
  }

  guard let metric = self.metric else {
    showAlertWithText("Select a metric", onViewController: self)
    return
  }

  guard let dimension = self.dimension else {
    showAlertWithText("Select a dimension", onViewController: self)
    return
  }

  let card = AnalyticsCard(cardName: cardName, dimension: dimension, metric: metric)
  CardManager.sharedManager.addCard(card)
}

This might be a bad thing to highlight but one line singletons :D

static let sharedManager = CardManager()

Protocol Extensions!

protocol StoryboardInstantiable {
    typealias ViewController
    static var storyboardID: String { get }
    static func instance(storyboard: UIStoryboard) -> ViewController?
}

extension StoryboardInstantiable {
    static func instance(storyboard: UIStoryboard) -> ViewController? {
        return storyboard.instantiateViewControllerWithIdentifier(Self.storyboardID) as? ViewController
    }
}

This lets us do things like: (no more global static constants for identifiers >_<)

LoginViewController.instance(storyboard)

Powerful Enums: This is very handy while making network calls

enum AnalyticsDimension: String, EnumCollectable {

    case PagePath = "rt:pagePath"
    case PageTitle = "rt:pageTitle"

    case ReferralPath = "rt:referralPath"
    case Campaign = "rt:campaign"
    case Source = "rt:source"
    case Medium = "rt:medium"
    case TrafficType = "rt:trafficType"
    case Keyword = "rt:keyword"

    case Browser = "rt:browser"
    case BrowserVersion = "rt:browserVersion"
    case OperatingSystem = "rt:operatingSystem"
    case OperatingSystemVersion = "rt:operatingSystemVersion"
		...
}

Crazy if-case-let and for-case-let

if case let savedCardsArray as NSArray = savedCards {
    for case let savedCard as NSDictionary in savedCardsArray  {
        guard let card = AnalyticsCard.from(savedCard) else { continue }
        cards.append(card)
    }
}

The only thing I really struggled was persistence and handling JSON responses due to swift’s strict type system (cake-walk in ObjC) though Mantle-like feature were possible via Lyft’s Mapper.