Serialize Reference isn't working with Custom Attributes (for example - Range)

Unity Engine
1

I am trying to combine serialize reference with my custom attribute but it ignores and use default drawer.
I tried to setup with Int property and Range attributes to see if the problem on my custom attribute implementation but it is not.

Sample script:

using System;
using System.Collections.Generic;
using System.Linq;
using UnityEngine;
#if UNITY_EDITOR
using UnityEditor;

#endif


public interface IFruit
{
}

public abstract class Fruit : IFruit
{
    public string fruitName;
}

[Serializable]
public class Orange : Fruit
{
    public enum OrangeType
    {
        Valencia,
        Blood,
        Jaffa
    }

    [SerializeField] private OrangeType orangeType = default;
}

[Serializable]
public class Apple : Fruit
{
    public enum AppleType
    {
        Gala,
        GrannySmith,
        RedDelicious
    }

    [SerializeField] private AppleType appleType = default;

    [SerializeField] [Range(0, 9)] private int count;
}

public class InspectorTesting : MonoBehaviour
{
    [SerializeReference] public List<IFruit> fruits = new List<IFruit>();
}

#if UNITY_EDITOR

[CustomEditor(typeof(InspectorTesting))]
public class InspectorTestingEditor : Editor
{
    private InspectorTesting source;
    private SerializedObject sourceRef;
    private SerializedProperty fruits;

    private int dropDownSelection;
    private Type[] types;
    private string[] names;

    private void OnEnable()
    {
        source = (InspectorTesting) target;
        sourceRef = serializedObject;

        GetProperties();
    }

    void GetProperties()
    {
        types = GetAllOfInterface(typeof(Fruit));
        names = new string[1];
        names[0] = "Add A Fruit!";
        names = names.Concat(GetAllOfInterfaceNames(typeof(Fruit))).ToArray();
        fruits = sourceRef.FindProperty("fruits");
    }

    public override void OnInspectorGUI()
    {
        DisplayProperties();
        sourceRef.ApplyModifiedProperties();
    }

    void DisplayProperties()
    {
        dropDownSelection = EditorGUILayout.Popup(dropDownSelection, names);
        if (dropDownSelection != 0)
        {
            var fruit = Activator.CreateInstance(types[dropDownSelection - 1]) as Fruit;
            fruit.fruitName = fruit.GetType().Name;
            source.fruits.Add(fruit);
            dropDownSelection = 0;
        }

        EditorGUILayout.PropertyField(fruits, true);
    }

    string[] GetAllOfInterfaceNames(Type _interfaceType)
    {
        return GetAllOfInterface(_interfaceType)
            .Select(x => x.Name)
            .ToArray();
    }

    Type[] GetAllOfInterface(Type _interfaceType)
    {
        return AppDomain.CurrentDomain.GetAssemblies()
            .SelectMany(s => s.GetTypes())
            .Where(x => _interfaceType.IsAssignableFrom(x) && x != _interfaceType && !x.IsAbstract)
            .OrderBy(x => x.Name)
            .ToArray();
    }
}

#endif
3 Likes
2

Same issue here. I think SerializeReference doesn’t work with polymorhisim on the inspector.
Unity 2019.3.0b11.