Subchapter 77.24

Usage

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iOS SDK usage

Usage · Instrument Feature Flags · PostHog/skills · Skills Docs

// This will trigger a screen view event with $screen_name: "HomeViewContent"
struct HomeView: View {
    var body: some View {
        HomeViewContent()
            .postHogScreenView()
    }
}

// This will trigger a screen view event with $screen_name: "My Home View" and an additional event property from_button: "start"
struct HomeView: View {
    var body: some View {
        HomeViewContent()
            .postHogScreenView("My Home View", ["from_button": "start"])
    }
}

let config = PostHogConfig(projectToken: "<ph_project_token>", host: "https://us.i.posthog.com")
config.captureElementInteractions = true // Disabled by default
PostHogSDK.shared.setup(config)

let config = PostHogConfig(projectToken: "<ph_project_token>", host: "https://us.i.posthog.com")
config.rageClickConfig.enabled = true // Enabled by default
config.rageClickConfig.minimumTapCount = 3 // Optional, default is 3
config.rageClickConfig.thresholdPoints = 30 // Optional, default is 30
config.rageClickConfig.timeoutInterval = 1.0 // Optional, default is 1.0s
PostHogSDK.shared.setup(config)

PostHogSDK.shared.identify("user_id_from_your_database",
                            userProperties: ["name": "Peter Griffin", "email": "peter@familyguy.com"],
                            userPropertiesSetOnce: ["date_of_first_log_in": "2024-03-01"])

PostHogSDK.shared.setPersonProperties(userPropertiesToSet: ["plan": "Pro++"])

PostHogSDK.shared.setPersonProperties(
    userPropertiesToSet: ["plan": "Pro++"],
    userPropertiesToSetOnce: ["first_seen_source": "ios"]
)

if let result = PostHogSDK.shared.getFeatureFlagResult("flag-key"), result.enabled {
    // Do something differently for this user

    // Optional: fetch the payload from the same evaluation result
    let matchedFlagPayload = result.payload
}

if let result = PostHogSDK.shared.getFeatureFlagResult("flag-key"), result.variant == "variant-key" { // replace "variant-key" with the key of your variant
    // Do something differently for this user

    // Optional: fetch the payload from the same evaluation result
    let matchedFlagPayload = result.payload
}

struct FlagPayload: Decodable {
    let title: String
}

if let result = PostHogSDK.shared.getFeatureFlagResult("flag-key"),
   let payload = result.payloadAs(FlagPayload.self) {
    // Use payload.title
}

class AppDelegate: NSObject, UIApplicationDelegate {
    func application(_ application: UIApplication, didFinishLaunchingWithOptions launchOptions: [UIApplication.LaunchOptionsKey : Any]? = nil) -> Bool {
        // register for `didReceiveFeatureFlags` notification before SDK initialization
        NotificationCenter.default.addObserver(
            self,
            selector: #selector(receiveFeatureFlags),
            name: PostHogSDK.didReceiveFeatureFlags,
            object: nil
        )

        let POSTHOG_PROJECT_TOKEN = "<ph_project_token>"
        // usually 'https://us.i.posthog.com' or 'https://eu.i.posthog.com'
        let POSTHOG_HOST = "https://us.i.posthog.com"

        let config = PostHogConfig(projectToken: POSTHOG_PROJECT_TOKEN, host: POSTHOG_HOST)

        PostHogSDK.shared.setup(config)

        return true
    }

    // The "receiveFeatureFlags" method will be called when the SDK receives the feature flags from the server.
    @objc func receiveFeatureFlags() {
        print("receiveFeatureFlags called")
    }
}

// Reload feature flags and check if a specific feature is enabled
PostHogSDK.shared.reloadFeatureFlags {
    if PostHogSDK.shared.isFeatureEnabled("flag-key") {
        // do something
    }
}

let config = PostHogConfig(projectToken: "<ph_project_token>", host: "https://us.i.posthog.com")
config.bootstrap = PostHogBootstrapConfig(
    distinctId: "distinct_id_of_your_user",
    isIdentifiedId: true,
    featureFlags: [
        "flag-1": true,
        "variant-flag": "control"
    ],
    featureFlagPayloads: nil
)
PostHogSDK.shared.setup(config)