Merge pull request #88 from VPDPersonal/master

Fix "ArgumentException: Empty path name is not legal" when assetPath is empty

Author: AlexeyTaranov

Editor/Dropdown/SerializeReferencePropertyDrawer_UIToolkit.cs

@@ -159,14 +159,22 @@ void RefreshDropdown(SerializedObject so)
                 var selectedType = TypeUtils.ExtractTypeFromString(prop.managedReferenceFullTypename);
                 var selectedTypeName = GetTypeName(selectedType);
                 var tooltipText = $"Type Full Name: {selectedType?.FullName}";
-                var isMissingType = TryGetMissingType(property, assetPath, out var missingType);
-                if (isMissingType)
+
+                var isMissingType = false;
+
+                if (!string.IsNullOrEmpty(assetPath))
                 {
-                    selectedTypeName = $"MISSING TYPE: {missingType.className}";
-                    tooltipText = missingType.GetDetailData();
-                    selectTypeButton.AddToClassList("error-bg");
+                    isMissingType = TryGetMissingType(property, assetPath, out var missingType);
+
+                    if (isMissingType)
+                    {
+                        selectedTypeName = $"MISSING TYPE: {missingType.className}";
+                        tooltipText = missingType.GetDetailData();
+                        selectTypeButton.AddToClassList("error-bg");
+                    }
                 }
-                else
+                
+                if (!isMissingType)
                 {
                     selectTypeButton.RemoveFromClassList("error-bg");
                 }
@@ -250,4 +258,4 @@ void ShowModifyWindow(TypeData typeData, long refId)
             }
         }
     }
-}
+}