public CollectionVM(CollectionModel model, CollectionWrkspcVM wrkspc)
{
_model = model;
Workspace = wrkspc;
Filter = new CollectionFilterData();
Columns = new ObservableCollection<PropertyDefinitionModel> { new PropertyDefinitionModel { Name = "id", Path="id", Type = Enums.PropertyType.String } };
this.AvailableProperties = new ObservableCollection<PropertyDefinitionModel>();
this.MaxItems = 20;
}