Hi,

I developed my own Inventory/Shop/Purchase system, but I have trouble serializing a dictionary ( I made use of the SerializableMap in Naninovel)

I have a customized ScritableObject class Item with below code:

using System.Collections;
using System.Collections.Generic;
using UnityEngine;
using System;

[CreateAssetMenu(fileName = "New Item", menuName = "Inventory/New Item", order = 0)]
[Serializable]
public class Item : ScriptableObject 
{
    public string itemName;
    public Sprite itemImage;

[TextArea]
public string itemInfo;

public bool gift;

public int price;
}

In my InventoryManager, I implement the SerializableMap as below

    

[Serializable]
public class InventoryMap: SerializableMap<Item, int>
{
    public InventoryMap(){}
    public InventoryMap(InventoryMap map){}
}

And I did similar job in InventoryManager as in https://naninovel.com/guide/state-manag ... stom-state

    

[Serializable]
public class GameState
{
    public InventoryMap SaveItemDict;
}

public static InventoryMap itemDict;

void Awake()
{
    if (instance != null)
    {
        Destroy(this);
        Debug.Log("singleton destroy...");
    }
    
    instance = this;
    itemDict = new InventoryMap();

    stateManager = Engine.GetService<IStateManager>();

}

private void OnEnable() {
    stateManager.AddOnGameSerializeTask(SerializeState);
    stateManager.AddOnGameDeserializeTask(DeserializeState);
}

private void OnDisable()
{
    stateManager.RemoveOnGameSerializeTask(SerializeState);
    stateManager.RemoveOnGameDeserializeTask(DeserializeState);
}

private void SerializeState (GameStateMap stateMap)
{
    var state = new GameState()
    {
        SaveItemDict = itemDict // I would suspect is there a copy issue/not just simple equal here
    };
    stateMap.SetState(state);
}

private UniTask DeserializeState(GameStateMap stateMap)
{

    var state = stateMap.GetState<GameState>();
    if (state is null) return UniTask.CompletedTask;

    itemDict = state.SaveItemDict;   // I would suspect is there a copy issue/not just simple equal here
    return UniTask.CompletedTask;
}

The issue could be described as below:

1. If I add an <Item, int> ( an item, number of Item added) to the bag, and save, it was working fine. I exit play mode in unity editor, restart the game, its working fine as well.
2. The problem happens when I exit the whole unity editor, when I restart the Unity Editor, it always gives an ArgumentNullException

ArgumentNullException: Value cannot be null.
Parameter name: key
System.Collections.Generic.Dictionary2[TKey,TValue].TryInsert (TKey key, TValue value, System.Collections.Generic.InsertionBehavior behavior) (at <695d1cc93cca45069c528c15c9fdd749>:0)
System.Collections.Generic.Dictionary2[TKey,TValue].set_Item (TKey key, TValue value) (at <695d1cc93cca45069c528c15c9fdd749>:0)
Naninovel.SerializableMap2[TKey,TValue].OnAfterDeserialize () (at Assets/Naninovel/Runtime/Common/Collections/SerializableMap.cs:67)
UnityEngine.JsonUtility:FromJson(String, Type)
Naninovel.StateMap:OnAfterDeserialize() (at Assets/Naninovel/Runtime/State/StateMap.cs:33)
Naninovel.GameStateMap:OnAfterDeserialize() (at Assets/Naninovel/Runtime/State/GameStateMap.cs:59)
UnityEngine.JsonUtility:FromJson(String)
Naninovel.<DeserializeDataAsync>d__20:MoveNext() (at Assets/Naninovel/Runtime/Common/SaveSlotManager/IOSaveSlotManager.cs:157)
UniRx.Async.CompilerServices.MoveNextRunner1:Run() (at Assets/Naninovel/ThirdParty/UniTask/UniRx.Async/CompilerServices/MoveNextRunner.cs:18)
UniRx.Async.UniTaskCompletionSource1:TryInvokeContinuation() (at Assets/Naninovel/ThirdParty/UniTask/UniRx.Async/UniTaskCompletionSource.cs:344)
UniRx.Async.UniTaskCompletionSource1:TrySetResult(String) (at Assets/Naninovel/ThirdParty/UniTask/UniRx.Async/UniTaskCompletionSource.cs:363)
UniRx.Async.CompilerServices.AsyncUniTaskMethodBuilder1:SetResult(String) (at Assets/Naninovel/ThirdParty/UniTask/UniRx.Async/CompilerServices/AsyncUniTaskMethodBuilder.cs:227)
Naninovel.<UnzipStringAsync>d__28:MoveNext() (at Assets/Naninovel/Runtime/Common/Utilities/StringUtils.cs:395)
UniRx.Async.CompilerServices.MoveNextRunner1:Run() (at Assets/Naninovel/ThirdParty/UniTask/UniRx.Async/CompilerServices/MoveNextRunner.cs:18)
UnityEngine.UnitySynchronizationContext:ExecuteTasks() (at /Users/bokken/buildslave/unity/build/Runtime/Export/Scripting/UnitySynchronizationContext.cs:107)

I tried debugging, I could see in StateMap, ObjectMap, the dictionary is loaded fine. After this step, it jumps into the ArgumentNullException, I could not figure out what is happening next and I suspected the way I use the SerializableMap to serialize the dictionary might be wrong (since it contains my custom class)

Could you provide any hint on this? Really appreciate your help.

Thanks!

Check how state management of a serializable map is handled in UnlockableManager.cs (under SaveServiceStateAsync and LoadServiceStateAsync specifically).

idaot wrote: ↑29 Oct 2022 20:11

Check how state management of a serializable map is handled in UnlockableManager.cs (under SaveServiceStateAsync and LoadServiceStateAsync specifically).

Hi,

Thanks for the instruction.

I implement exactly the same as in SaveServiceState and LoadServiceStateAsync, it seems like that doesn't help, still get the same null error.

My implementation is as follow:

My Map extend from SerializableMap

    [Serializable]
    public class InventoryMap: SerializableMap<Item, int>
    {
        public InventoryMap () : base() { }
        public InventoryMap(InventoryMap map): base (map){ }
    }

GameState, instead of GlobalState, I would like to save to slot

    [Serializable]
    public class GameState
    {
        public InventoryMap SaveItemDict = new InventoryMap();
    }

SerializeState and DeserializeState

    

private void SerializeState (GameStateMap stateMap)
    {
        var state = new GameState
        {
            SaveItemDict = new InventoryMap(itemDict),
        };
        Debug.Log("SerializeState: " + state.SaveItemDict[0]);
        stateMap.SetState(state);
    }

private UniTask DeserializeState(GameStateMap stateMap)
{

    var state = stateMap.GetState<GameState>();
    if (state is null) return UniTask.CompletedTask;

    itemDict = new InventoryMap(state.SaveItemDict);
    Display();
    return UniTask.CompletedTask;
}

During debugging, the error will arise when the game starts, seems like during SerializaState method is called, still get some ArgumentNullExceptions:
Value cannot be null.
Parameter name: key

It sounds like you are triggering the script in the editor. Make sure the InventoryManager fulfills the engine service requirements (https://naninovel.com/guide/engine-serv ... e-services) and check the Inventory extension for reference (https://naninovel.com/guide/inventory.html#inventory)

hey,

Thanks for the guide! I think I figure out the root cause for this. I did not put [Serializable] when I created my Scriptable Object Item, the [Serializable] was added afterwards. So it leads to the fact that the previous added Item is not able to serialize and result in Null Key error when it got deserialized.

I will also check the engine service requirements accordingly and the Inventory extension as well!

Thanks!