fix: dynamically enable or disable PostHogWidget

Author: ioannisj

lib/src/posthog.dart

@@ -1,4 +1,4 @@
-import 'package:meta/meta.dart';
+import 'package:flutter/foundation.dart';
 
 import 'package:posthog_flutter/src/error_tracking/posthog_error_tracking_autocapture_integration.dart';
 import 'package:posthog_flutter/src/error_tracking/posthog_exception.dart';
@@ -14,6 +14,9 @@ class Posthog {
 
   PostHogConfig? _config;
 
+  @internal
+  final sessionRecordingActive = ValueNotifier<bool>(false);
+
   factory Posthog() {
     return _instance;
   }
@@ -42,6 +45,10 @@ class Posthog {
   Future<void> setup(PostHogConfig config) {
     _config = config; // Store the config
 
+    if (config.sessionReplay) {
+      sessionRecordingActive.value = true;
+    }
+
     _installFlutterIntegrations(config);
 
     return _posthog.setup(config);
@@ -200,6 +207,7 @@ class Posthog {
   Future<void> close() {
     _config = null;
     _currentScreen = null;
+    sessionRecordingActive.value = false;
     PosthogObserver.clearCurrentContext();
 
     // Uninstall Flutter integrations
@@ -217,13 +225,18 @@ class Posthog {
   ///
   /// [resumeCurrent] - If true (default), resumes recording of the current session.
   /// If false, starts a new session and begins recording.
-  Future<void> startSessionRecording({bool resumeCurrent = true}) =>
-      _posthog.startSessionRecording(resumeCurrent: resumeCurrent);
+  Future<void> startSessionRecording({bool resumeCurrent = true}) async {
+    await _posthog.startSessionRecording(resumeCurrent: resumeCurrent);
+    sessionRecordingActive.value = true;
+  }
 
   /// Stops the current session recording if one is in progress.
   ///
   /// This method will have no effect if PostHog is not enabled.
-  Future<void> stopSessionRecording() => _posthog.stopSessionRecording();
+  Future<void> stopSessionRecording() async {
+    await _posthog.stopSessionRecording();
+    sessionRecordingActive.value = false;
+  }
 
   /// Returns whether session replay is currently active.
   Future<bool> isSessionReplayActive() => _posthog.isSessionReplayActive();

lib/src/posthog_widget.dart

@@ -31,19 +31,51 @@ class PostHogWidgetState extends State<PostHogWidget> {
     super.initState();
 
     final config = Posthog().config;
-    if (config == null || !config.sessionReplay) {
+    if (config == null) {
       return;
     }
 
-    _throttleDuration = config.sessionReplayConfig.throttleDelay;
+    if (config.sessionReplay) {
+      _initComponents(config);
+      _changeDetector?.start();
+    }
+
+    // start listening for session recording toggles
+    Posthog().sessionRecordingActive.addListener(_onSessionRecordingChanged);
+  }
 
+  void _initComponents(PostHogConfig config) {
+    _throttleDuration = config.sessionReplayConfig.throttleDelay;
     _screenshotCapturer = ScreenshotCapturer(config);
     _nativeCommunicator = NativeCommunicator();
-
     _changeDetector = ChangeDetector(_onChangeDetected);
+  }
+
+  void _onSessionRecordingChanged() {
+    if (Posthog().sessionRecordingActive.value) {
+      _startRecording();
+    } else {
+      _stopRecording();
+    }
+  }
+
+  void _startRecording() {
+    final config = Posthog().config;
+    if (config == null) {
+      return;
+    }
+
+    if (_changeDetector == null) {
+      _initComponents(config);
+    }
+
     _changeDetector?.start();
   }
 
+  void _stopRecording() {
+    _changeDetector?.stop();
+  }
+
   // This works as onRootViewsChangedListeners
   void _onChangeDetected() {
     if (_isThrottling) {
@@ -97,6 +129,8 @@ class PostHogWidgetState extends State<PostHogWidget> {
 
   @override
   void dispose() {
+    Posthog().sessionRecordingActive.removeListener(_onSessionRecordingChanged);
+
     _throttleTimer?.cancel();
     _throttleTimer = null;
     _changeDetector?.stop();

lib/src/replay/change_detector.dart

@@ -1,5 +1,4 @@
 import 'package:flutter/widgets.dart';
-import 'package:posthog_flutter/posthog_flutter.dart';
 
 /// A class that detects changes in the UI and executes a callback when changes occur.
 ///
@@ -51,11 +50,6 @@ class ChangeDetector {
   /// Executes the [onChange] callback and schedules itself for the next frame
   /// if the change detector is still running.
   void _onFrameRendered() {
-    final config = Posthog().config;
-    if (config == null || !config.sessionReplay) {
-      return;
-    }
-
     if (!_isRunning) {
       return;
     }