setVisitorIdFrom

The setVisitorIdFrom methods read the pk_vid query parameter from a URL (string or URL) and, if it is valid, apply the same rules as setVisitorID to set the visitor ID. Call setVisitorIdFrom(deepLink:) or setVisitorIdFrom(url:) when the user opens your app from a link that carries pk_vid, for example a universal / app link opened in Safari or another browser on the same phone, or a link followed from an in-app web view. That way you can reuse the same visitor ID for the website (or web content) and the app on that phone.

Syntax

let stringResult = PiwikTracker.sharedInstance()?.setVisitorIdFrom(deepLink: "deepLink") ?? false

let urlResult = PiwikTracker.sharedInstance()?.setVisitorIdFrom(url: url) ?? false

BOOL result = [[PiwikTracker sharedInstance] setVisitorIdFromDeepLink:@"deepLink"];

BOOL result = [[PiwikTracker sharedInstance] setVisitorIdFromURL:url];

Parameters

• deepLink string, optional. Any URL string the system can parse as a URL; it must include a pk_vid query parameter whose first 16 characters are a valid visitor ID (lowercase hexadecimal 0-9a-f, same rule as visitorID). Example: piwik://example?pk_vid=25a3c7d060a94360.
• url URL, optional. Same requirements as deepLink, as an NSURL / URL value.

Returns

true if the visitor ID was updated from pk_vid. false if it was left unchanged: the URL is missing or cannot be parsed, pk_vid is absent, the value is shorter than 16 characters, or the first 16 characters are not valid lowercase hex (see visitorID).

Examples

To set the visitor ID from a deep link delivered to application(_:open:options:):

func application(_ app: UIApplication, open url: URL, options: [UIApplication.OpenURLOptionsKey: Any] = [:]) -> Bool {
    return PiwikTracker.sharedInstance()?.setVisitorIdFrom(url: url) ?? false
}

- (BOOL)application:(UIApplication *)app openURL:(NSURL *)url options:(NSDictionary<UIApplicationOpenURLOptionsKey, id> *)options {
    return [[PiwikTracker sharedInstance] setVisitorIdFromURL:url];
}

Attach the .onOpenURL modifier to the root view of your App:

@main
struct MyApp: App {
    var body: some Scene {
        WindowGroup {
            ContentView()
                .onOpenURL { url in
                    PiwikTracker.sharedInstance()?.setVisitorIdFrom(url: url)
                }
        }
    }
}

To set the visitor ID from a string-based deep link:

PiwikTracker.sharedInstance()?.setVisitorIdFrom(deepLink: "piwik://example?pk_vid=25a3c7d060a94360")

[[PiwikTracker sharedInstance] setVisitorIdFromDeepLink:@"piwik://example?pk_vid=25a3c7d060a94360"];

Notes

• If pk_vid is longer than 16 characters, only the first 16 are used (they must still satisfy the hex format check).
• For cross-platform flows, see Cross-platform tracking.

Related methods

• visitorID