Delphi Readonly TCollection in designtime

Question

I'm trying to create and register a custom editor for TCollection in Delphi XE5. I tried several things, including inheriting the TCollectionProperty class. I figured it's enough to override the GetColOptions function as follows:

function TMycollectionEditor.GetColOptions: TColOptions;
begin
  Result: = [];
end;

But nothing happened, it is still possible to add, remove and move items. so by searching more I found the code of the Edit function and wrote the following:

procedure TMycollectionEditor.Edit;
var
  ACollection: TCollection;
  APersistent: TPersistent;
begin
  APersistent: = GetComponent (0);

  while (APersistent <> nil) and not (APersistent is TComponent)
    APersistent: = GetPersistentOwner (APersistent);

  ACollection: = TCollection (TMy component (APersistent) .MyCollection);

  ShowCollectionEditorClass (Designer, GetEditorClass, TComponent (APersistent), ACollection, GetName, GetColOptions);
end;

This also did not change anything in the native editor's workings.

What am I doing wrong? Is this a good practice to do what I'm trying to do? Note: my goal is not the same as this post

Update

I made a temporary change to the method that works (except via context menu or double click [using the ExecuteVerb method of the inherited property of TCollection])

    procedure TMycollectionEditor.Edit;
    var
      ACollection: TCollection;
      APersistent: TPersistent;
    begin
      APersistent: = GetComponent (0);

      while (APersistent <> nil) and not (APersistent is TComponent)
        APersistent: = GetPersistentOwner (APersistent);

      ACollection: = TCollection (TMy component (APersistent) .MyCollection);
//    [update bellow]
      with ShowCollectionEditorClass (Designer, GetEditorClass, TComponent (APersistent), ACollection, GetName, GetColOptions) do
      begin
        AddCmd.Enabled := False;
        ListView1.DragMode := dmManual;
        ToolBar1.Visible := False;
        ToolBar2.Visible := False;
      end;

    end;