In this chapter, you have seen how you can design a logic tier comprising of business objects that encapsulate the raw datasets retrieved from the data tier. You have also designed reusable UI components by inheriting from existing .NET Compact Framework controls and also via user controls.

Through the TaskDetailViewer form, you've learned how to build the interfaces to handle master-detail data. You've learned the various approaches to handling file attachments and how you can build a repository to store uploaded files through the FileManager class. Through the HistoryList control, you've learned how you can use an inherited ListView control to achieve custom formatting and sorting. And through the ProductList control, you've learned how to load and store XML data in the database.

You've also made use of the data tier you've built in the previous chapter to commit an entire dataset to the database and vice versa from the main AccountViewer form. More importantly, you have used one of the core features of data-driven programming—data binding to bind presentation-layer controls to your business objects.

You have also used SQL-based paging for both the Oracle Lite and SQL Server CE databases to return result sets of a fixed size and explored how to build a user control to handle the navigation between pages of data.

At this point you have already built more than half of the sales force application, and you now have a functional sales force application working on your mobile device that can at least store and retrieve data! The next few chapters aim to add some additional functionality to your sales force application. In the next chapter, you will see how you can build a robust search facility to search through file content and data.