he key to configuring the ALV Grid Control for your particular application is the structures that are passed by the application to an ALV Grid instance before or during list display. For some simple extensions of your ALV Grid instance, you only need to set the right parameter and pass the table or structure by using method set_table_for_first_display.
The ALV Grid Control solves this problem. Its user interface provides a set of generic functions (e.g., sorting, filtering) for handling tabular data. It also confers the many benefits of controls technology to users, enabling more operations by mouse, and interaction with other controls, such as drag-and-drop. Developers simply plug the ALV Grid Control into their applications and the tool takes care of the rest. You do not need to do any further programming to offer users these functions. How you “plug” the control into an application is the first thing I will show you in this month’s blog. So lets get started!
In all the aspects, enhancements are more powerful than modifications, even given all the modification support that transaction SPAU offers. The reason is due to an important difference between an enhancement and a modification that stems from the conceptual difference between the two technologies.
In contrast to enhancements in the Enhancement Framework, modifications are physically part of the object they modify. This means that every single modification gets lost in an upgrade and needs to be re-inserted even in cases where the underlying SAP object has not changed at all!