具有可编辑集合的MVVM示例，其中View不直接使用模型类型

I have read many people say that model types should not be exposed to View, but instead it should be wrapped inside ViewModel types. Is there some example where I can see how is synchronization done between ViewModel and Model data, using Entity Framework. In particular, I need an example of editable collection (example: DataGrid or DataForm displaying Customer list).I have read many people say that model types sh