[unity] Fixed SkeletonGraphic related import error occurring occasionally on first import. Error message was usually 'Skeleton JSON file not set for SkeletonData asset'. Closes #1226.

spine-unity/Assets/Spine/Editor/spine-unity/Editor/SpineEditorUtilities.cs

@@ -453,6 +453,9 @@ namespace Spine.Unity.Editor {
 
 
 		public static class DataReloadHandler {
+
+			internal static Dictionary<int, string> savedSkeletonDataAssetAtSKeletonGraphicID = new Dictionary<int, string>();
+
 #if NEWPLAYMODECALLBACKS
 			internal static void OnPlaymodeStateChanged (PlayModeStateChange stateChange) {
 #else
@@ -462,6 +465,7 @@ namespace Spine.Unity.Editor {
 			}
 
 			public static void ReloadAllActiveSkeletonsEditMode () {
+
 				if (EditorApplication.isPaused) return;
 				if (EditorApplication.isPlaying) return;
 				if (EditorApplication.isCompiling) return;
@@ -475,10 +479,20 @@ namespace Spine.Unity.Editor {
 					if (skeletonDataAsset != null) skeletonDataAssetsToReload.Add(skeletonDataAsset);
 				}
 
+				// Under some circumstances (e.g. on first import) SkeletonGraphic objects 
+				// have their skeletonGraphic.skeletonDataAsset reference corrupted
+				// by the instance of the ScriptableObject being destroyed but still assigned.
+				// Here we save the skeletonGraphic.skeletonDataAsset asset path in order
+				// to restore it later.
 				var activeSkeletonGraphics = GameObject.FindObjectsOfType<SkeletonGraphic>();
 				foreach (var sg in activeSkeletonGraphics) {
 					var skeletonDataAsset = sg.skeletonDataAsset;
-					if (skeletonDataAsset != null) skeletonDataAssetsToReload.Add(skeletonDataAsset);
+					if (skeletonDataAsset != null) {
+						var assetPath = AssetDatabase.GetAssetPath(skeletonDataAsset);
+						var sgID = sg.GetInstanceID();
+						savedSkeletonDataAssetAtSKeletonGraphicID[sgID] = assetPath;
+						skeletonDataAssetsToReload.Add(skeletonDataAsset);
+					}
 				}
 
 				foreach (var sda in skeletonDataAssetsToReload) {
@@ -780,6 +794,22 @@ namespace Spine.Unity.Editor {
 #endif
 				}
 				// Any post processing of images
+
+				// Under some circumstances (e.g. on first import) SkeletonGraphic objects 
+				// have their skeletonGraphic.skeletonDataAsset reference corrupted
+				// by the instance of the ScriptableObject being destroyed but still assigned.
+				// Here we restore broken skeletonGraphic.skeletonDataAsset references.
+				var skeletonGraphicObjects = Resources.FindObjectsOfTypeAll(typeof(SkeletonGraphic)) as SkeletonGraphic[];
+				foreach (var skeletonGraphic in skeletonGraphicObjects) {
+					
+					if (skeletonGraphic.skeletonDataAsset == null) {
+						var skeletonGraphicID = skeletonGraphic.GetInstanceID();
+						if (DataReloadHandler.savedSkeletonDataAssetAtSKeletonGraphicID.ContainsKey(skeletonGraphicID)) {
+							string assetPath = DataReloadHandler.savedSkeletonDataAssetAtSKeletonGraphicID[skeletonGraphicID];
+							skeletonGraphic.skeletonDataAsset = (SkeletonDataAsset)AssetDatabase.LoadAssetAtPath<SkeletonDataAsset>(assetPath);
+						}
+					}
+				}
 			}
 
 			static void ReloadSkeletonData (string skeletonJSONPath) {

spine-unity/Assets/Spine/Runtime/spine-unity/Modules/SkeletonGraphic/SkeletonGraphic.cs

@@ -64,7 +64,7 @@ namespace Spine.Unity {
 		protected override void OnValidate () {
 			// This handles Scene View preview.
 			base.OnValidate ();
-			if (this.IsValid) {
+			if (this.IsValid) { 
 				if (skeletonDataAsset == null) {
 					Clear();
 				} else if (skeletonDataAsset.skeletonJSON == null) {
@@ -100,12 +100,16 @@ namespace Spine.Unity {
 
 				}
 			} else {
-				if (skeletonDataAsset != null)
+				// Under some circumstances (e.g. sometimes on the first import) OnValidate is called
+				// before SpineEditorUtilities.ImportSpineContent, causing an unnecessary exception.
+				// The (skeletonDataAsset.skeletonJSON != null) condition serves to prevent this exception.
+				if (skeletonDataAsset != null && skeletonDataAsset.skeletonJSON != null)
 					Initialize(true);
-			}				
+			}
 		}
 
 		protected override void Reset () {
+
 			base.Reset();
 			if (material == null || material.shader != Shader.Find("Spine/SkeletonGraphic (Premultiply Alpha)"))
 				Debug.LogWarning("SkeletonGraphic works best with the SkeletonGraphic material.");			
@@ -154,8 +158,17 @@ namespace Spine.Unity {
 		}
 
 		protected override void Awake () {
+
 			base.Awake ();
 			if (!this.IsValid) {
+#if UNITY_EDITOR
+				// workaround for special import case of open scene where OnValidate and Awake are
+				// called in wrong order, before setup of Spine assets.
+				if (!Application.isPlaying) {
+					if (this.skeletonDataAsset != null && this.skeletonDataAsset.skeletonJSON == null)
+						return;
+				}
+#endif
 				Initialize(false);
 				Rebuild(CanvasUpdate.PreRender);
 			}
@@ -311,5 +324,5 @@ namespace Spine.Unity {
 			//this.UpdateMaterial(); // TODO: This allocates memory.
 		}
 		#endregion
-	}
+	} 
 }