Unity含派生类的List使用[SerializeReference]触发序列化错误

为自定义抽象类的List添加[SerializeReference]特性后，Unity编辑器内部触发无法查看调用栈细节的空引用异常。触发条件：仅在Inspector窗口中操作该序列化列表时报错，单纯查看列表内容不会触发错误。

核心代码结构 #

数据容器类 #

[System.Serializable]
public class SingleSpellManager 
{ 
    [SerializeReference]
    public List<ModifierClass> OnCast_Modifier = new List<ModifierClass>();
    //[SerializeReference] do this one later
    //public List<ModifierClass> OnHit_Modifier = new List<ModifierClass>();
}

抽象基类与派生类 #

[System.Serializable]
public abstract class ModifierClass 
{ // 内部代码与错误无关 
}

// 派生类
[System.Serializable]
public class Projectile : ModifierClass
{ // 内部代码与错误无关 
}

[System.Serializable]
public class Delay : ModifierClass
{ // 内部代码与错误无关 
}

GUI列表引用逻辑 #

为跨脚本操作方便，在UI管理脚本中直接引用该列表，疑似错误诱因：

public class SCC_GUI_Manager : MonoBehaviour
{
    public void Load_ModifierList_OnCast()
    {   // 清空面板
        foreach (Transform child in ModifierList_OnCast_Space.transform) 
        {GameObject.Destroy(child.gameObject);}

        // 引用目标列表
        OnCast_ModifierList = SelectedSpell.OnCast_Modifier;

        // 加载面板元素
        foreach(ModifierClass CC in OnCast_ModifierList)
        {
            GameObject newElm = Instantiate(Modifier_elm, ModifierList_OnCast_Space.transform);
            newElm.GetComponent<ModifierElm_UI>().SCC_GUI_Manager_scpt = this;
            newElm.GetComponent<ModifierElm_UI>().Modifier = CC;
        }
    }
}

列表操作逻辑 #

移动列表元素的操作会稳定触发错误：

public class SCC_GUI_Manager : MonoBehaviour
{   // 将列表元素移动到新索引位置
    public void Move(int oldIndex, int newIndex, int onWhatTrigger)
    {
        if(onWhatTrigger == 0)
        {   // 执行移动
            ModifierClass item = OnCast_ModifierList[oldIndex];
            OnCast_ModifierList.RemoveAt(oldIndex);
            OnCast_ModifierList.Insert(newIndex, item);
        }
    }
}

控制台错误信息 #

NullReferenceException: SerializedObject of SerializedProperty has been Disposed.
UnityEditor.SerializedProperty.FindPropertyRelativeInternal (System.String propertyPath) (at <88872b21b1e746a7ad699974a2be8304>:0)
UnityEditor.SerializedProperty.FindPropertyRelative (System.String relativePropertyPath) (at <88872b21b1e746a7ad699974a2be8304>:0)
UnityEditor.UIElements.Bindings.SerializedObjectBindingContext.BindPropertyRelative (UnityEngine.UIElements.IBindable field, UnityEditor.SerializedProperty parentProperty) (at <68890c016c7a40d7ab0d5ba9aecf643f>:0)
UnityEditor.UIElements.Bindings.SerializedObjectBindingContext.BindTree (UnityEngine.UIElements.VisualElement element, UnityEditor.SerializedProperty parentProperty) (at <68890c016c7a40d7ab0d5ba9aecf643f>:0)
UnityEditor.UIElements.Bindings.SerializedObjectBindingContext.ContinueBinding (UnityEngine.UIElements.VisualElement element, UnityEditor.SerializedProperty parentProperty) (at <68890c016c7a40d7ab0d5ba9aecf643f>:0)
UnityEditor.UIElements.Bindings.DefaultSerializedObjectBindingImplementation+BindingRequest.Bind (UnityEngine.UIElements.VisualElement element) (at <68890c016c7a40d7ab0d5ba9aecf643f>:0)
UnityEngine.UIElements.VisualTreeBindingsUpdater.Update () (at <6350d5f72ec34638985fbaab06c4c559>:0)
UnityEngine.UIElements.VisualTreeUpdater.UpdateVisualTreePhase (UnityEngine.UIElements.VisualTreeUpdatePhase phase) (at <6350d5f72ec34638985fbaab06c4c559>:0)
UnityEngine.UIElements.Panel.UpdateBindings () (at <6350d5f72ec34638985fbaab06c4c559>:0)
UnityEngine.UIElements.UIElementsUtility.UnityEngine.UIElements.IUIElementsUtility.UpdateSchedulers () (at <6350d5f72ec34638985fbaab06c4c559>:0)
UnityEngine.UIElements.UIEventRegistration.UpdateSchedulers () (at <6350d5f72ec34638985fbaab06c4c559>:0)
UnityEditor.RetainedMode.UpdateSchedulers () (at <68890c016c7a40d7ab0d5ba9aecf643f>:0)

内容的提问来源于stack exchange，提问作者Gilang Agung