public async Task <ObservableCollection <ServiceType> > GetServiceTypes(ServiceTypeFilter serviceTypeFilter)
        {
            var ret = new ObservableCollection <ServiceType>();

            foreach (
                var s in
                await
                Post <ServiceTypeFilter, ObservableCollection <DtoServiceType> >("GetServiceTypes",
                                                                                 serviceTypeFilter))
            {
                ret.Add(ServiceTypeConverter.DtoToViewModel(s));
            }
            return(ret);
        }
        /// <summary>
        ///     Method returns filtered ServiceTypes
        /// </summary>
        /// <param name="filter">Filter to select specific service types</param>
        /// <returns>Collection of service types</returns>
        public async Task <ObservableCollection <DtoServiceType> > GetServiceTypes(ServiceTypeFilter filter)
        {
            var ret = new ObservableCollection <DtoServiceType>();

            try
            {
                using (var data = Context)
                {
                    foreach (var st in await data.ServiceType
                             .Where(st =>
                                    (filter.IsCourse == null || st.isCourse == filter.IsCourse) &&
                                    (filter.SportId == null || st.SportType.id == filter.SportId))
                             .Take(TakeTop).ToListAsync())
                    {
                        ret.Add(ServiceTypeConverter.DataAccsessToDto(st));
                    }
                }
            }
            catch (Exception)
            {
                ret = null;
            }
            return(ret);
        }