Unity SerializeReferenceExtensions

Inspired by this post.

The SerializeReference attribute, added in Unity 2019.3, makes it possible to serialize references to interfaces and abstract classes.

The SubclassSelector attribute allows you to easily set subclasses of those abstract classes in the Editor that are serialized by SerializeReference attribute.

Features

• Easily set subclass by popup.
• [New] Type finding by fuzzy finder.
• [New] Override the type name and path by the AddTypeMenu attribute.

🔰 Usage

using System;
using UnityEngine;

public class Example : MonoBehaviour {

	// The type that implements ICommand will be displayed in the popup.
	[SerializeReference, SubclassSelector]
	ICommand m_Command;

	// Collection support
	[SerializeReference, SubclassSelector]
	ICommand[] m_Commands = Array.Empty<ICommand>();

	void Start () {
		m_Command?.Execute();

		foreach (ICommand command in m_Commands) {
			command?.Execute();
		}
	}

	// Nested type support
	[Serializable]
	public class NestedCommand : ICommand {
		public void Execute () {
			Debug.Log("Execute NestedCommand");
		}
	}

}

public interface ICommand {
	void Execute ();
}

[Serializable]
public class DebugCommand : ICommand {

	[SerializeField]
	string m_Message;

	public void Execute () {
		Debug.Log(m_Message);
	}
}

[Serializable]
public class InstantiateCommand : ICommand {

	[SerializeField]
	GameObject m_Prefab;

	public void Execute () {
		UnityEngine.Object.Instantiate(m_Prefab,Vector3.zero,Quaternion.identity);
	}
}

// Menu override support
[AddTypeMenu("Example/Add Type Menu Command")]
[Serializable]
public class AddTypeMenuCommand : ICommand {
	public void Execute () {
		Debug.Log("Execute AddTypeMenuCommand");
	}
}

Supported Types

The SubclassSelector attribute supports types that meet the following conditions.

• Class
• Public
• Not abstract
• Not generic
• Not unity object
• Serializable attribute is applied.