[unity] Fixed broken inspector preview in Unity7 2019. Closes #1331.

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

@@ -30,7 +30,7 @@
 
 #define SPINE_SKELETON_MECANIM
 
- #if (UNITY_2017_4 || UNITY_2018)
+ #if (UNITY_2017_4 || UNITY_2018_1_OR_NEWER )
  #define SPINE_UNITY_2018_PREVIEW_API
  #endif
 

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

@@ -106,8 +106,13 @@ namespace Spine.Unity.Editor {
 		}
 
 		void OnSelectionChange () {
+		#if UNITY_2019_1_OR_NEWER
+			SceneView.duringSceneGui -= this.OnSceneGUI;
+			SceneView.duringSceneGui += this.OnSceneGUI;
+		#else
 			SceneView.onSceneGUIDelegate -= this.OnSceneGUI;
 			SceneView.onSceneGUIDelegate += this.OnSceneGUI;
+		#endif
 
 			bool noSkeletonRenderer = false;
 
@@ -148,7 +153,11 @@ namespace Spine.Unity.Editor {
 			isPrefab = false;
 			boneName = string.Empty;
 			bone = null;
+		#if UNITY_2019_1_OR_NEWER
+			SceneView.duringSceneGui -= this.OnSceneGUI;
+		#else
 			SceneView.onSceneGUIDelegate -= this.OnSceneGUI;
+		#endif
 		}
 
 		void OnDestroy () {

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

@@ -201,8 +201,13 @@ namespace Spine.Unity.Editor {
 			Icons.Initialize();
 
 			// Drag and Drop
+		#if UNITY_2019_1_OR_NEWER
+			SceneView.duringSceneGui -= DragAndDropInstantiation.SceneViewDragAndDrop;
+			SceneView.duringSceneGui += DragAndDropInstantiation.SceneViewDragAndDrop;
+		#else
 			SceneView.onSceneGUIDelegate -= DragAndDropInstantiation.SceneViewDragAndDrop;
 			SceneView.onSceneGUIDelegate += DragAndDropInstantiation.SceneViewDragAndDrop;
+		#endif
 
 			EditorApplication.hierarchyWindowItemOnGUI -= HierarchyHandler.HandleDragAndDrop;
 			EditorApplication.hierarchyWindowItemOnGUI += HierarchyHandler.HandleDragAndDrop;