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Why does my app crash when a button is clicked?

I am trying to make a friends function into my Unity game. Each friend will have their own line with their name and a few buttons (challenge, about, etc.).
I have a friend row prefab and I instantiate it into the parent list for each friend.
It works just fine, until I click the challenge button, which whould call a method that takes in two parameters: the UId of the friend, and their username (two strings).
I am using Firebase Realtime Database for database.
void RetrieveFriendList(object sender, ValueChangedEventArgs args) {
foreach(Transform childTransform in listParent.GetComponentInChildren<Transform>()) {
GameObject.Destroy(childTransform.gameObject);
}
friends.Clear();
foreach (DataSnapshot s in args.Snapshot.Children) {
friends.Add(s.Key);
GameObject newRow = Instantiate(friendRowPrefab);
newRow.transform.Find("Deny").gameObject.GetComponent<Button>().onClick.RemoveAllListeners();
newRow.transform.Find("Challenge").gameObject.GetComponent<Button>().onClick.RemoveAllListeners();
newRow.transform.SetParent(listParent.transform);
newRow.transform.localScale = new Vector3(1f, 1f, 1f);
newRow.transform.Find("Text_Name").gameObject.GetComponent<TMPro.TMP_Text>().text = s.Child("username").Value.ToString();
string retrievedStatus = s.Child("type").Value.ToString();
if (retrievedStatus == "sent") {
newRow.transform.Find("Status").gameObject.GetComponent<TMPro.TMP_Text>().text = "Friend request sent";
} else if (retrievedStatus == "request") {
newRow.transform.Find("Status").gameObject.GetComponent<TMPro.TMP_Text>().text = "Incoming friend request";
newRow.transform.Find("Accept").gameObject.SetActive(true);
newRow.transform.Find("Deny").gameObject.SetActive(true);
newRow.transform.Find("Accept").gameObject.GetComponent<Button>().onClick.AddListener(delegate { AcceptFriendRequest(s.Key); });
newRow.transform.Find("Deny").gameObject.GetComponent<Button>().onClick.AddListener(delegate { DenyFriendRequest(s.Key); });
} else if (retrievedStatus == "friends") {
newRow.transform.Find("Challenge").gameObject.SetActive(true);
Debug.Log(s.Key + " - " + s.Child("username").Value.ToString());
newRow.transform.Find("Challenge").gameObject.GetComponent<Button>().onClick.AddListener(delegate { ChallengeFriend(s.Key, s.Child("username").Value.ToString()); }); //this is the line that causes the crash
newRow.transform.Find("About").gameObject.SetActive(true);
newRow.transform.Find("Status").gameObject.SetActive(false);
}
}
FirebaseDatabase.DefaultInstance.GetReference("users").Child(auth.CurrentUser.UserId).Child("friends").ValueChanged -= RetrieveFriendList;
}

What's likely happening is that the underlying C++ representation of your database snapshot is being cleaned up before your button accesses it. See this bug.
The easiest thing to do would be to find this line:
newRow.transform.Find("Challenge").gameObject.GetComponent<Button>().onClick.AddListener(delegate { ChallengeFriend(s.Key, s.Child("username").Value.ToString()); }); //this is the line that causes the crash
and turn it into something like:
var challengeKey = s.Key;
var challengeUsername = s.Child("username").Value.ToString();
newRow.transform.Find("Challenge").gameObject.GetComponent<Button>().onClick.AddListener(delegate { ChallengeFriend(challengeKey, challengeUsername); });
This way you retrieve the values you need (key and username) at the time of the callback rather than in the context of the button click (at some arbitrary point in the future after this function has returned). If you still get a crash, you may have to .Clone or .CopyTo the data -- but I believe that once an object is retrieved from the underlying snapshot it should be a full on C# object obeying the expected C# GC rules.
You also may experience null reference exceptions if the snapshot hits a local cache first -- so make sure you have null checks around everything (generally a good practice whenever you're hitting the web).

Windows 10 Iot Core app crashes if I try to open a PWM pin

I want to open a PWM pin to my buzzer. But If I try to call the pwmController.OpenPin(6) method, the app crashes with an System.Runtime.InteropServices.SEHException.
I had already double checked the sample sources like the ms-iot-samples. But I cannot see what my problems are.
An idea was that some permissions are missing, but if I try to add for exmaple <iot:Capability Name="lowLevelDevices" />, I cannot longer build the application.
Source
private PwmPin buzzerPin;
private PwmController pwmController;
public RainbowHAT()
{
// ... do something else
InitAsync();
}
private async void InitAsync()
{
Logger.Log(this, "Init");
// Setup PWM controller.
if (LightningProvider.IsLightningEnabled)
{
LowLevelDevicesController.DefaultProvider = LightningProvider.GetAggregateProvider();
}
var pwmControllers = await PwmController.GetControllersAsync(LightningPwmProvider.GetPwmProvider());
if (pwmControllers == null || pwmControllers.Count < 2)
{
throw new OperationCanceledException("Operation canceled due missing GPIO controller");
}
pwmController = pwmControllers[1];
pwmController.SetDesiredFrequency(50);
// Setup buzzer
buzzerPin = pwmController.OpenPin(13); <-- CRASH
buzzerPin.SetActiveDutyCyclePercentage(0.05);
buzzerPin.Start();
}
I also tried the following tip to reduce the min required Windows version, but this does not help, too.

PWM Controller needs Lightning support. So you need to set the controller driver as Direct Memory Mapped Driver. Here is a sample about PWM on Raspberry Pi.
You also need to modify the code as following:
private async void InitAsync()
{
Logger.Log(this, "Init");
// Setup PWM controller.
if (LightningProvider.IsLightningEnabled)
{
var pwmControllers = await PwmController.GetControllersAsync(LightningPwmProvider.GetPwmProvider());
if (pwmControllers == null || pwmControllers.Count < 2)
{
throw new OperationCanceledException("Operation canceled due missing GPIO controller");
}
pwmController = pwmControllers[1];
pwmController.SetDesiredFrequency(50);
// Setup buzzer
buzzerPin = pwmController.OpenPin(13);
buzzerPin.SetActiveDutyCyclePercentage(0.05);
buzzerPin.Start();
}
}

How to download data from Firebase?

I'm attempting to retrieve some data from a Firebase database. I've been able to do it fine in the past, but there's something wrong with my GetValueAsync() code below. When debugging it gets stuck at the "await reference.Database" line, but I'm not sure what I'm doing wrong. When running without debugging, none of the information is ever retrieved.
I'm uncertain if the problem is with the path, or the await/async function. Debugging shows that loggedUserId is storing the value before referencing it in the next line, but the rest of the function never completes or faults. The application compiles but I'm never able to capture any info from the snapshot.
The format of my database is "users" -> 78cVqzA8qNTNigsao3VvdnM0Qol2 (Which is correct) -> (several data pairs such as level : 1, lives : 3, etc)
public static async void GetUserData()
{
FirebaseApp app = FirebaseApp.DefaultInstance;
app.SetEditorDatabaseUrl("https://narwhaltrivia.firebaseio.com/");
if (app.Options.DatabaseUrl != null) app.SetEditorDatabaseUrl(app.Options.DatabaseUrl);
DatabaseReference reference = Firebase.Database.FirebaseDatabase.DefaultInstance.RootReference;
loggedUserId = FirebaseAuth.DefaultInstance.CurrentUser.UserId;
await reference.Database.GetReference("users").Child(loggedUserId).GetValueAsync().ContinueWith(task =>
{
if (task.IsFaulted)
{
Debug.LogError("Error retrieving user data");
return;
}
if (task.IsCompleted)
{
DataSnapshot userSnapshot = task.Result;
loggedEmail = userSnapshot.Child("email").GetRawJsonValue();
loggedCurrentScore = userSnapshot.Child("currentScore").GetRawJsonValue();
loggedLevel = userSnapshot.Child("level").GetRawJsonValue();
loggedLives = userSnapshot.Child("lives").GetRawJsonValue();
loggedRound = userSnapshot.Child("round").GetRawJsonValue();
loggedTotalScore = userSnapshot.Child("totalScore").GetRawJsonValue();
return;
}
});
}

Enable/Disable VR from code

How can I set the display to stereoscopic programmatically in Unity for an app deployed to an Android device?
I want a UI menu where the user can toggle between "VR mode" and normal mode. I do not want VR mode by default as it should be an option at run-time. I know there is a setting for "Virtual Reality Supported" in the build settings, but again, I do not want this enabled by default.

Include using UnityEngine.XR; at the top.
Call XRSettings.LoadDeviceByName("") with empty string followed by XRSettings.enabled = false; to disable VR in the start function to disable VR.
When you want to enable it later on, call XRSettings.LoadDeviceByName("daydream") with the VR name followed by XRSettings.enabled = true;.
You should wait for a frame between each function call. That requires this to be done a corutine function.
Also, On some VR devices, you must go to Edit->Project Settings->Player and make sure that Virtual Reality Supported check-box is checked(true) before this will work. Then you can disable it in the Start function and enable it whenever you want.
EDIT:
This is known to work on some VR devices and not all VR devices. Although, it should work on Daydream VR. Complete code sample:
IEnumerator LoadDevice(string newDevice, bool enable)
{
XRSettings.LoadDeviceByName(newDevice);
yield return null;
XRSettings.enabled = enable;
}
void EnableVR()
{
StartCoroutine(LoadDevice("daydream", true));
}
void DisableVR()
{
StartCoroutine(LoadDevice("", false));
}
Call EnableVR() to enable vr and DisableVR() to disable it. If you are using anything other than daydream, pass the name of that VR device to the LoadDevice function in the EnableVR() function.

For newer builds of Unity (e.g. 2019.4.0f1) you can use the XR Plugin Management package.
To enable call:
XRGeneralSettings.Instance.Manager.InitializeLoader();
To disable call:
XRGeneralSettings.Instance.Manager.DeinitializeLoader();

I'm using Unity 2021 but this probably works in earlier versions, I'm also using XR Plug-in Management.
Start:
XRGeneralSettings.Instance.Manager.StartSubsystems();
Stop:
XRGeneralSettings.Instance.Manager.StopSubsystems();
Full documentation at:
https://docs.unity3d.com/Packages/com.unity.xr.management#4.0/manual/EndUser.html

2020.3.14f1
Doesn't work for me, I get this error when running my Android app.
Call to DeinitializeLoader without an initialized manager.Please make
sure wait for initialization to complete before calling this API.
[RuntimeInitializeOnLoadMethod(RuntimeInitializeLoadType.AfterAssembliesLoaded)]
static void TryToDeinitializeOculusLoader()
{
XRGeneralSettings.Instance.Manager.DeinitializeLoader();
}
More context.
I try to unload the Oculus loader, before he manages to load the plugin.
I have an Android app, and the Oculus loader calls Application.Quit because the device is not an Oculus headset.
Waiting for XRGeneralSettings.Instance.Manager.isInitializationComplete takes too long.
Tried all RuntimeInitializeLoadType annotations.
OculusLoader.cs
#elif (UNITY_ANDROID && !UNITY_EDITOR)
[RuntimeInitializeOnLoadMethod(RuntimeInitializeLoadType.AfterAssembliesLoaded)]
static void RuntimeLoadOVRPlugin()
{
var supported = IsDeviceSupported();
if (supported == DeviceSupportedResult.ExitApplication)
{
Debug.LogError("\n\nExiting application:\n\nThis .apk was built with the Oculus XR Plugin loader enabled, but is attempting to run on a non-Oculus device.\nTo build for general Android devices, please disable the Oculus XR Plugin before building the Android player.\n\n\n");
Application.Quit();
}
if (supported != DeviceSupportedResult.Supported)
return;
try
{
if (!NativeMethods.LoadOVRPlugin(""))
Debug.LogError("Failed to load libOVRPlugin.so");
}
catch
{
// handle Android standalone build with Oculus XR Plugin installed but disabled in loader list.
}
}
#endif
SOLUTION
Made my build class extend IPreprocessBuildWithReport
public void OnPreprocessBuild(BuildReport report)
{
DisableXRLoaders(report);
}
///https://docs.unity3d.com/Packages/com.unity.xr.management#3.2/manual/EndUser.html
/// Do this as a setup step before you start a build, because the first thing that XR Plug-in Manager does at build time
/// is to serialize the loader list to the build target.
void DisableXRLoaders(BuildReport report)
{
XRGeneralSettingsPerBuildTarget buildTargetSettings;
EditorBuildSettings.TryGetConfigObject(XRGeneralSettings.k_SettingsKey, out buildTargetSettings);
if (buildTargetSettings == null)
{
return;
}
XRGeneralSettings settings = buildTargetSettings.SettingsForBuildTarget(report.summary.platformGroup);
if (settings == null)
{
return;
}
XRManagerSettings loaderManager = settings.AssignedSettings;
if (loaderManager == null)
{
return;
}
var loaders = loaderManager.activeLoaders;
// If there are no loaders present in the current manager instance, then the settings will not be included in the current build.
if (loaders.Count == 0)
{
return;
}
var loadersForRemoval = new List<XRLoader>();
loadersForRemoval.AddRange(loaders);
foreach (var loader in loadersForRemoval)
{
loaderManager.TryRemoveLoader(loader);
}
}

public void Awake() {
StartCoroutine(SwitchToVR(()=>{
Debug.Log("Switched to VR Mode");
}));
//For disable VR Mode
XRSettings.enabled = false;
}
IEnumerator SwitchToVR(Action callback) {
// Device names are lowercase, as returned by `XRSettings.supportedDevices`.
// Google original, makes you specify
// string desiredDevice = "daydream"; // Or "cardboard".
// XRSettings.LoadDeviceByName(desiredDevice);
// this is slightly better;
string[] Devices = new string[] { "daydream", "cardboard" };
XRSettings.LoadDeviceByName(Devices);
// Must wait one frame after calling `XRSettings.LoadDeviceByName()`.
yield return null;
// Now it's ok to enable VR mode.
XRSettings.enabled = true;
callback.Invoke();
}

in app purchase issue in windows store app

I have created an app with in app purchase and tested it with CurrentAppSimulator and works fine but when i create the package for app it fails
This is my code for which i am creating package
public async System.Threading.Tasks.Task InAppInit()
{
var listing = await CurrentApp.LoadListingInformationAsync();
// Delux Unlock - Durable
var unlockFeatureDelux = listing.ProductListings.FirstOrDefault(p => p.Value.ProductId == "deluxe" && p.Value.ProductType == ProductType.Durable);
isDeluxPurchased = CurrentApp.LicenseInformation.ProductLicenses[unlockFeatureDelux.Value.ProductId].IsActive;
deluxProductID = unlockFeatureDelux.Value.ProductId;
// Standard Unlock - Durable
var unlockFeatureStandard = listing.ProductListings.FirstOrDefault(p => p.Value.ProductId == "standard" && p.Value.ProductType == ProductType.Durable);
isStarndardPurchased = CurrentApp.LicenseInformation.ProductLicenses[unlockFeatureStandard.Value.ProductId].IsActive;
standardProductID = unlockFeatureStandard.Value.ProductId;
}
I am calling this method OnLaunched in App.xaml.cs

Based on our discussion here is what I would do:
The LoadListingInformationAsync method uses internet and if the user does not have an internet connection then it will throw an exception. So I suggest to wrap this whole stuff into a try/ctach block
As we see the ProductListings does not contain any item. I don't know how this list is populated, but as long as your app is not in the store I would not be surprised when that list is empty (Maybe someone can help out here... but i did not find anything regarding this in the docs). So for this I would just simply check if the feature you need is in the list... With this your package will pass the test you mentioned and you can upload it. If the list is also empty when the package is installed via the store, then something with the IAP setting is wrong (but that is related to the store..)
And a general comment: Obviously this code is not complete... You need some code for purchasing the IAPs and here we only get the Ids.. (But I think you only pasted the relevant part anyway.)
So all this in code:
public async System.Threading.Tasks.Task InAppInit()
{
try
{
var listing = await CurrentApp.LoadListingInformationAsync();
if (listing.ProductListings.ContainsKey("deluxe"))
{
// Delux Unlock - Durable
var unlockFeatureDelux = listing.ProductListings.FirstOrDefault(p => p.Value.ProductId == "deluxe" && p.Value.ProductType == ProductType.Durable);
isDeluxPurchased = CurrentApp.LicenseInformation.ProductLicenses[unlockFeatureDelux.Value.ProductId].IsActive;
deluxProductID = unlockFeatureDelux.Value.ProductId;
}
else
{
//There is no deluxe IAP defined... so something with your IAP stuff is wrong...
}
if (listing.ProductListings.ContainsKey("standard"))
{
// Standard Unlock - Durable
var unlockFeatureStandard = listing.ProductListings.FirstOrDefault(p => p.Value.ProductId == "standard" && p.Value.ProductType == ProductType.Durable);
isStarndardPurchased = CurrentApp.LicenseInformation.ProductLicenses[unlockFeatureStandard.Value.ProductId].IsActive;
standardProductID = unlockFeatureStandard.Value.ProductId;
}
else
{
//same as for Delux
}
}
catch
{
//Show this on the UI...
}
}