I use Google Analytics to collect usage statistics across both my web and mobile applications. There are a few great AngularJS and other libraries that track page usage automatically when a controller is initialized. Using these concepts I wanted to create my own similar approach in Swift. The end result of this is the creation of a simple BaseController which makes an analytics call when viewDidLoad is called.
class BaseController: UIViewController { override func viewDidLoad() { super.viewDidLoad() Analytics().screenView(self.controllerName) } }
Deconstructing this simple one line method call you will notice there are an extension method called controllerName passed into a static method on the analytics struct. The controllerName references the below extension method and simply is used to get the name of the UIViewController so that we can track usage by the screen name. Below is a snippet with the code for this extension method.
extension UIViewController { var controllerName: String { return NSStringFromClass(self.classForCoder).componentsSeparatedByString(".").last! } }
The analytics struct is an anti corruption layer that I’ve added to my app to wrap the underlying Google Analytics code. This also provides a layer of abstraction which helps combat the fact that Xcode randomly makes the Google Analytics Objective-C references invalid. The Analytics struct is used in two places in my app. First it is initialized in my app delegate, then it is used within my BaseController to record feature usage.
Before we get to the Analytics struct code below is the snippet using in my app delegate used to create a default tracker with our Google Analytics key.
Analytics.createTracker(Analytics.GAToken.QAKey.rawValue)
Once initialized the Analytics struct method screenView is used on each viewDidLoad call to record that a UIViewController has been viewed.
import Google public struct Analytics { enum GAToken: String { case QAKey = "UPDATE-WITH-QA-KEY" case ProdKey = "UPDATE-WITH-PROD-KEY" } public static func createTracker(key: String) { GAI.sharedInstance().trackerWithTrackingId(key) GAI.sharedInstance().logger.logLevel = GAILogLevel.None GAI.sharedInstance().trackUncaughtExceptions = true } private func getTracker() -> GAITracker { return GAI.sharedInstance().defaultTracker } public func screenView(name: String) { let tracker = getTracker() tracker.set(kGAIScreenName, value: name) let builder = GAIDictionaryBuilder.createScreenView() tracker.send(builder.build() as [NSObject : AnyObject]) } }
Although there are more comprehensive Analytics (Google or other) approaches I’ve found this straightforward approach provides the basics in away that works for me.
Helpful Links:
- gist with source code available here
- Google Analytics on CocoaPods here
- Google Analytics for iOS resources
