Exposed ExpandRelated to the view and view model

The `TopicQueryOptions.ExpandRelated` value is now relayed via the `RelationshipAttributeTopicViewModel` to its view, which uses that to configure the web service call used to bind the `SelectableTreeView` control. This allows users to configure whether or not a relationship should automatically be expanded as part of the `RelationshipAttribute` configuration in OnTopic.

Author: JeremyCaney

OnTopic.Editor.AspNetCore/Areas/Editor/Views/Editor/Components/Relationship/Default.cshtml

@@ -16,7 +16,7 @@
 <script type="text/javascript">
   Ext.onReady(function(){
     var tree                    = new OnTopic.SelectableTreeView({
-      dataUrl                   : '/OnTopic/Json/@rootTopicKey?ShowRoot=@descriptor.ShowRoot&ShowAll=true&RelatedNamespace=@descriptor.Key&RelatedTopicID=@Model.CurrentTopic.Id&AttributeName=@descriptor.AttributeKey&AttributeValue=@descriptor.AttributeValue',
+      dataUrl                   : '/OnTopic/Json/@rootTopicKey?ShowRoot=@descriptor.ShowRoot&ShowAll=true&RelatedNamespace=@descriptor.Key&RelatedTopicID=@Model.CurrentTopic.Id&AttributeName=@descriptor.AttributeKey&AttributeValue=@descriptor.AttributeValue&ExpandRelated=@descriptor.ExpandRelated',
       checkAscendants           : @((descriptor.CheckAscendants is true).ToString().ToLower()),
       backingField              : '@Html.IdFor(m => m.Value)'
     });

OnTopic.Editor.Models/Metadata/RelationshipAttributeTopicViewModel.cs

@@ -25,6 +25,15 @@ public class RelationshipAttributeTopicViewModel: QueryableTopicListAttributeTop
     /// </summary>
     public bool? ShowRoot { get; set; }
 
+    /*==========================================================================================================================
+    | PROPERTY: EXPAND RELATED?
+    \-------------------------------------------------------------------------------------------------------------------------*/
+    /// <summary>
+    ///   Determines whether or not the tree panel should be expanded to ensure visibility of any related (checked)
+    ///   relationships upon load. Defaults to <c>true</c>.
+    /// </summary>
+    public bool? ExpandRelated { get; set; }
+
     /*==========================================================================================================================
     | PROPERTY: CHECK ASCENDANTS
     \-------------------------------------------------------------------------------------------------------------------------*/