Add UI filter for null data provider types

Author: keveleigh

Assets/MRTK/Core/Inspectors/Profiles/DataProviderAccessServiceInspector.cs

@@ -162,6 +162,13 @@ protected bool RenderDataProviderEntry(int index, GUIContent removeContent, Syst
 
             var serviceType = GetDataProviderConfiguration(index).ComponentType;
 
+
+            SerializedProperty typeProperty = providerProperties.componentType.FindPropertyRelative("reference");
+            if (!string.IsNullOrEmpty(typeProperty.stringValue) && Type.GetType(typeProperty.stringValue) == null && !MixedRealityProjectPreferences.ShowNullDataProviders)
+            {
+                return false;
+            }
+
             using (new EditorGUILayout.VerticalScope(EditorStyles.helpBox))
             {
                 using (new EditorGUILayout.HorizontalScope())

Assets/MRTK/Core/Utilities/Editor/Preferences/MixedRealityProjectPreferences.cs

@@ -122,6 +122,34 @@ public static bool RunOptimalConfiguration
 
         #endregion Run optimal configuration analysis on Play
 
+        #region Display null data providers
+
+        private static readonly GUIContent NullDataProviderContent = new GUIContent("Show null data providers in the input profile", "Mainly used for debugging unexpected behavior. Will render null data providers in red in the inspector.");
+        private const string NULL_DATA_PROVIDER_KEY = "MixedRealityToolkit_Editor_NullDataProviders";
+        private static bool nullDataProviderPrefLoaded;
+        private static bool nullDataProvider;
+
+        /// <summary>
+        /// Whether to show null data providers in the profile UI.
+        /// </summary>
+        /// <remarks>Mainly used for debugging unexpected behavior. Data providers may be null due to a namespace change or while using an incompatible Unity version.</remarks>
+        public static bool ShowNullDataProviders
+        {
+            get
+            {
+                if (!nullDataProviderPrefLoaded)
+                {
+                    nullDataProvider = ProjectPreferences.Get(NULL_DATA_PROVIDER_KEY, false);
+                    nullDataProviderPrefLoaded = true;
+                }
+
+                return nullDataProvider;
+            }
+            set => ProjectPreferences.Set(NULL_DATA_PROVIDER_KEY, nullDataProvider = value);
+        }
+
+        #endregion Display null data providers
+
         #region Project configuration cache
 
         // This section contains data that gets cached for future reference to help detect configuration
@@ -212,6 +240,12 @@ void GUIHandler(string searchContext)
                     RunOptimalConfiguration = runOptimalConfig;
                 }
 
+                bool nullProviders = EditorGUILayout.Toggle(NullDataProviderContent, ShowNullDataProviders);
+                if (ShowNullDataProviders != nullProviders)
+                {
+                    ShowNullDataProviders = nullProviders;
+                }
+
                 EditorGUIUtility.labelWidth = prevLabelWidth;
             }