In the PerformFilter method in the DialogViewController Class. sections are added to a list if their elements are matches to the searched text. But instead of using the RootElement Add method, the list of sections just overwrites the internal Sections list. Since the Add method is not called, then the Parent property on the Sections is not set. So all my sections in the root have a null Parent property value after I type a character into the search bar.
I would suggest changing the following line in the PerformFilter method.
this.Root.Sections = lists;
or something along those lines.
Created attachment 4257 [details]
this is the suggested change to the performfilter method in the dialogviewcontroller class