MVVM灯光:使用DataService来检索数据库项

I am working on a sample MVVM Light project and am implementing the SimpleIoc ViewModelLocator. I have been able to construct a IRepositoryService that retrieves information from a database (i.e., Company, Employee, etc.) and stores the info into an ObservableCollection. The IRepositoryService then returns the ObservableCollection to the ViewModel. Here is how this is implemented:I am working on a sample MVVM Light project and