Skip to content

WebView User Session Continuity

For cases where your app uses WebViews, we provide a mechanism to inject a user session, so that the CMP on the WebView is not shown every time the user opens it.

To implement this feature the SDK offers the method getUserSessionData, which returns a String (JSON) with the user session.

This data must then be injected into a global variable called UC_UI_USER_SESSION_DATA in your WKWebView. 

let sessionData = UsercentricsCore.shared.getUserSessionData()

let script = """
window.ucMobileSdk = {
    getUserSessionData: function() {
        return '\(sessionData)';
    }
}
"""

let userScript = WKUserScript(source: script, injectionTime: .atDocumentStart, forMainFrameOnly: true)
let contentController = WKUserContentController()
contentController.addUserScript(userScript)

let preferences = WKPreferences()
preferences.javaScriptEnabled = true

let webConfiguration = WKWebViewConfiguration()
webConfiguration.preferences = preferences
webConfiguration.userContentController = contentController

webView = WKWebView(frame: .zero, configuration: webConfiguration)
webView.uiDelegate = self

let myURL = URL(string:"https://<some_url>")
let myRequest = URLRequest(url: myURL!)
webView.load(myRequest)

This data must be injected using a JavaScriptInterface with a method getSessionData.

webView.settings.javaScriptEnabled = true
webView.settings.domStorageEnabled = true

webView.addJavascriptInterface(SampleJavascriptInterface(userSessionData), "ucMobileSdk")
webView.loadUrl("https://<some_url>")

class SampleJavascriptInterface(private val userSessionData: UserSessionData) {

    @JavascriptInterface
    fun getUserSessionData(): String? {
        return userSessionData
    }
}

This data must then be injected into a global variable called UC_UI_USER_SESSION_DATA. However due to the webview_flutter library limitations, it is important that you guarantee in some way or another that the data is available at the time the Usercentrics script is executed in the webview. For example:

FutureBuilder<String>(
  future: Usercentrics.userSessionData,
  builder: (context, snapshot) {
    final userSessionData = snapshot.data;
    if (userSessionData == null) return const SizedBox();
    return WebView(
      onWebViewCreated: (WebViewController controller) async {
        this.controller = controller;
        await controller.loadFlutterAsset('assets/webview_index.html'); // loadUrl or whatever
      },
      onPageFinished: (String url) async {
        await controller?.runJavascript("""
        window.UC_UI_USER_SESSION_DATA = $userSessionData;
        window.dispatchEvent(new Event('Usercentrics_userSessionData_injected'));
        """);
      },
      javascriptMode: JavascriptMode.unrestricted,
      debuggingEnabled: true,
    );
  }),
)

function addUsercentricsScript() {
    var settingsId = 'Yi9N3aXia';
    var script = document.createElement('script');
    script.id = 'usercentrics-cmp';
    script.setAttribute('data-settings-id', settingsId);
    script.setAttribute('src', 'https://app.usercentrics.eu/browser-ui/latest/bundle_legacy.js');
    script.async = true;
    document.head.appendChild(script);
}

window.addEventListener("Usercentrics_userSessionData_injected", function() {
    addUsercentricsScript();
});

See more here.

This data must then be injected into a global variable called UC_UI_USER_SESSION_DATA in your WebView injectedJavaScriptBeforeContentLoaded property. 

<WebView
    javaScriptEnabled={true}
    domStorageEnabled={true}
    injectedJavaScriptBeforeContentLoaded={`window.UC_UI_USER_SESSION_DATA = ${userSessionData};`.toString()}
    source=... />

See more here.

This feature is intended to be used with a single SettingsID

For seamless integration and support, it is imperative that the SDK utilized within your application employs the same SettingsID as the one implemented within the WebView. The utilization of divergent SettingsIDs between the SDK and WebView are not supported by the SDK.

WebView Banner and the Native SDK

When displaying a WebView and adhering to the provided instructions, it's important to note that any changes to consent made by the user within the Web banner will not automatically be reflected in the Native SDK. This means that if a user alters their consent settings, these changes won't be communicated back to the native environment of your application.

To ensure that your application's functionality remains unaffected by these potential discrepancies, it's crucial to implement a mechanism that re-synchronizes consent statuses whenever the WebView is dismissed. This proactive approach will help maintain consistency across your application's consent management processes.

Compatibility

User Session injection is only supported if your WebView is running version 1.4.0 or higher of the Usercentrics Browser SDK.