Implement a one shot request (ViewModel)

ViewModel.kt

class ProductsViewModel(val productsRepository: ProductsRepository): ViewModel() {
   private val _sortedProducts = MutableLiveData<List<ProductListing>>()
   val sortedProducts: LiveData<List<ProductListing>> = _sortedProducts

   /**
    * Called by the UI when the user clicks the appropriate sort button
    */
   fun onSortAscending() = sortPricesBy(ascending = true)
   fun onSortDescending() = sortPricesBy(ascending = false)

   private fun sortPricesBy(ascending: Boolean) {
       viewModelScope.launch {
           // suspend and resume make this database request main-safe
           // so our ViewModel doesn't need to worry about threading
           _sortedProducts.value =
                   productsRepository.loadSortedProducts(ascending)
       }
   }
}