Displaying Table contents is one of the important requirement in any application. ALV is the short form of ABAP List viewer. ALV is used to display the table of contents. It generally shows the data of the internal table. It can also be used to export data in to Excel file.
REUSE_ALV_GRID_DISPLAY: It is based on the function module. DDIC Structure, Field catalog und merged field catalog are parameters of the function module.
CL_GUI_ALV_GRID: It is one of the old models of the SAP ALV List. This old model facilitates users to edit and input data in the list. Therefore the user must have authorization.
CL_SALV_TABLE: It is the new model of SAP ALV List. It has a simplified user interface. The User cannot edit or input data. The functions are very similar to old models. The new ALV models can be editable by using the old ALV Types and Adapter Class.
CL_SALV_GUI_TABLE_IDA: It is the newly introduced ALV with Integrated data access(IDA). It has a very high performance. It is directly connected to a database or view.
Most important variables used in ALV List:
- Internal table : It contains the table of data which is read from the Database table.
- Containers: It is used to show the ALV Table in a certain area of the screen.
- Field Catalog: It contains information such as the Column heading, breadth of the column and the data type of the column.
- ALV Object: It is the reference variable which specfies the ALV Object.
- Layout: It is variable of type structure ( lvc_s_layo ). As the name clearly states that it is used to change the layout of the table.
Creation of ALV List is an easy task. But to bring additional features in the ALV List such as editing fields, disabling fields, Column changes, Highlighting rows or columns, Icons, sorting data, functions, events are more complicated.
