feat: Update package.json to 1.2.1

Fix compatibility for less than Unity 2021.3

Assets/MackySoft/MackySoft.SerializeReferenceExtensions/Editor/CopyAndPasteProperty.cs

@@ -1,4 +1,5 @@
-#if UNITY_2019_3_OR_NEWER
+// NOTE: managedReferenceValue getter is available only in Unity 2021.3 or later.
+#if UNITY_2021_3_OR_NEWER
 using UnityEditor;
 using UnityEngine;
 

Assets/MackySoft/MackySoft.SerializeReferenceExtensions/Editor/ManagedReferenceUtility.cs

@@ -8,14 +8,19 @@ namespace MackySoft.SerializeReferenceExtensions.Editor {
 	public static class ManagedReferenceUtility {
 
 		public static object SetManagedReference (this SerializedProperty property,Type type) {
-			object result;
+			object result = null;
+
+#if UNITY_2021_3_OR_NEWER
+			// NOTE: managedReferenceValue getter is available only in Unity 2021.3 or later.
 			if (property.managedReferenceValue != null)
 			{
 				// Restore an previous values from json.
 				string json = JsonUtility.ToJson(property.managedReferenceValue);
 				result = JsonUtility.FromJson(json, type);
 			}
-			else
+#endif
+
+			if (result == null)
 			{
 				result = (type != null) ? Activator.CreateInstance(type) : null;
 			}

Assets/MackySoft/MackySoft.SerializeReferenceExtensions/package.json

@@ -2,7 +2,7 @@
 	"name": "com.mackysoft.serializereference-extensions",
 	"displayName": "SerializeReference Extensions",
 	"author": { "name": "MackySoft", "url": "https://github.com/mackysoft" },
-	"version": "1.2.0",
+	"version": "1.2.1",
 	"unity": "2021.3",
 	"description": "Provide popup to specify the type of the field serialized by the [SerializeReference] attribute in the inspector.",
 	"keywords": [ "SerializeReference", "Editor" ],

README.md

@@ -15,6 +15,9 @@ The `SubclassSelector` attribute allows you to easily set subclasses of those ab
 - Easily set subclass by popup.
 - **[New]** Type finding by fuzzy finder.
 - **[New]** Override the type name and path by the `AddTypeMenu` attribute.
+- **[New]** Restore values of previous object from JSON when subclass is changed.
+- **[New]** Copy & Paste the subclass properties.
+- **[New]** Available `CustomPropertyDrawer` for subclasses.
 
 ## 📥 Installation