[unity] Fix SpineAttributes not seeing sibling fields in arrays and serialized structs/classes.

spine-unity/Assets/spine-unity/Editor/SpineAttributeDrawers.cs

@@ -74,7 +74,7 @@ namespace Spine.Unity.Editor {
 				return;
 			}
 
-			var dataField = property.serializedObject.FindProperty(TargetAttribute.dataField);
+			var dataField = property.FindBaseOrSiblingProperty(TargetAttribute.dataField);
 			if (dataField != null) {
 				if (dataField.objectReferenceValue is SkeletonDataAsset) {
 					skeletonDataAsset = (SkeletonDataAsset)dataField.objectReferenceValue;
@@ -108,7 +108,7 @@ namespace Spine.Unity.Editor {
 		}
 
 		public ISkeletonComponent GetTargetSkeletonComponent (SerializedProperty property) {
-			var dataField = property.serializedObject.FindProperty(TargetAttribute.dataField);
+			var dataField = property.FindBaseOrSiblingProperty(TargetAttribute.dataField);
 
 			if (dataField != null) {
 				var skeletonComponent = dataField.objectReferenceValue as ISkeletonComponent;
@@ -282,10 +282,9 @@ namespace Spine.Unity.Editor {
 				menu.AddSeparator("");
 			}
 
-
 			Skin defaultSkin = data.Skins.Items[0];
+			var slotProperty = property.FindBaseOrSiblingProperty(TargetAttribute.slotField);
 
-			SerializedProperty slotProperty = property.serializedObject.FindProperty(targetAttribute.slotField);
 			string slotMatch = "";
 			if (slotProperty != null) {
 				if (slotProperty.propertyType == SerializedPropertyType.String)
@@ -369,7 +368,7 @@ namespace Spine.Unity.Editor {
 			if (string.IsNullOrEmpty(atlasAssetFieldName))
 				atlasAssetFieldName = "atlasAsset";
 
-			atlasProp = property.serializedObject.FindProperty(atlasAssetFieldName);
+			atlasProp = property.FindBaseOrSiblingProperty(atlasAssetFieldName);
 
 			if (atlasProp == null) {
 				EditorGUI.LabelField(position, "ERROR:", "Must have AtlasAsset variable!");

spine-unity/Assets/spine-unity/Editor/SpineInspectorUtility.cs

@@ -79,6 +79,20 @@ namespace Spine.Unity.Editor {
 			return EditorGUIUtility.ObjectContent(null, type).image as Texture2D;
 		}
 
+		#region SerializedProperty Helpers
+		public static SerializedProperty FindBaseOrSiblingProperty (this SerializedProperty property, string propertyName) {
+			if (string.IsNullOrEmpty(propertyName)) return null;
+			SerializedProperty relativeProperty = property.serializedObject.FindProperty(propertyName); // baseProperty
+			if (relativeProperty == null) { // If no baseProperty, find sibling property.
+				int nameLength = property.name.Length;
+				string propertyPath = property.propertyPath;
+				propertyPath = propertyPath.Remove(propertyPath.Length - nameLength, nameLength) + propertyName;
+				relativeProperty = property.serializedObject.FindProperty(propertyPath);
+			}
+			return relativeProperty;
+		}
+		#endregion
+
 		#region Layout Scopes
 		static GUIStyle grayMiniLabel;
 		public static GUIStyle GrayMiniLabel {