Plugins - Implemented features enable/disable UI

src/Artemis.Core/Plugins/DataModelExpansions/Internal/BaseDataModelExpansion.cs

@@ -20,7 +20,7 @@ namespace Artemis.Core.DataModelExpansions
         /// </summary>
         public ReadOnlyCollection<PropertyInfo> HiddenProperties => HiddenPropertiesList.AsReadOnly();
 
-        internal DataModel InternalDataModel { get; set; }
+        internal DataModel? InternalDataModel { get; set; }
 
         /// <summary>
         ///     Called each frame when the data model should update
@@ -28,6 +28,12 @@ namespace Artemis.Core.DataModelExpansions
         /// <param name="deltaTime">Time in seconds since the last update</param>
         public abstract void Update(double deltaTime);
 
+        internal void InternalUpdate(double deltaTime)
+        {
+            if (InternalDataModel != null)
+                Update(deltaTime);
+        }
+
         /// <summary>
         ///     Override to provide your own data model description. By default this returns a description matching your plugin
         ///     name and description

src/Artemis.Core/Plugins/Plugin.cs

@@ -129,14 +129,15 @@ namespace Artemis.Core
 
         internal void RemoveFeature(PluginFeature feature)
         {
+            if (feature.IsEnabled)
+                throw new ArtemisCoreException("Cannot remove an enabled feature from a plugin");
+            
             _features.Remove(feature);
-            feature.InternalDisable();
             feature.Dispose();
 
             OnFeatureRemoved(new PluginFeatureEventArgs(feature));
         }
-
-
+        
         internal void SetEnabled(bool enable)
         {
             if (IsEnabled == enable)

src/Artemis.Core/Plugins/PluginFeature.cs

@@ -87,8 +87,8 @@ namespace Artemis.Core
                         throw new ArtemisPluginLockException(LoadException);
                     }
 
-                    IsEnabled = true;
                     CreateLockFile();
+                    IsEnabled = true;
 
                     // Allow up to 15 seconds for plugins to activate.
                     // This means plugins that need more time should do their long running tasks in a background thread, which is intentional