Complete Unity with ejected RN - Shaunakdas/doc_genius_native GitHub Wiki

AndroidJavaClass activityClass;
AndroidJavaObject activity, packageManager;
AndroidJavaObject launch;
activityClass = new AndroidJavaClass("com.unity3d.player.UnityPlayer");
activity = activityClass.GetStatic<AndroidJavaObject>("currentActivity");
Debug.Log("Calling unityActivity");
activity.Call("Call");
string key = "key";
Debug.Log(activity.Call<string>("getPrefsValue",key));
activity.Call("setPrefsValue",key, "value");
Debug.Log(activity.Call<string>("getPrefsValue",key));

const key = 'key';
NativeModules.ActivityStarter.getPrefsValue(key, (value) => { console.log(value); });
NativeModules.ActivityStarter.setPrefsValue(key, 'old');
NativeModules.ActivityStarter.getPrefsValue(key, (value) => { console.log(value); });