This helps us to implement all the features mentioned very effectively.
Using ALV, We can have three types of reports:
1. Simple Report
2. Block Report
3. Hierarchical Sequential Report
There are some function modules which will enable to produce the above reports without much effort.
All the definitions of internal tables, structures and constants are declared in a type-pool called SLIS.
1. SIMPLE REPORT.
The important function modules are
a. Reuse_alv_list_display
b. Reuse_alv_fieldcatalog_merge
c. Reuse_alv_events_get
d. Reuse_alv_commentary_write
e. Reuse_alv_grid_display
A. REUSE_ALV_LIST_DISPLAY : This is the function module which prints the data.
The important parameters are :
I. Export :
i. I_callback_program : report id
ii. I_callback_pf_status_set : routine where a user can set his own pf status or change the functionality of the existing pf status
iii. I_callback_user_command : routine where the function codes are handled
iv. I_structure name : name of the dictionary table
v. Is_layout : structure to set the layout of the report
vi. It_fieldcat : internal table with the list of all fields and their attributes which are to be printed (this table can be populated automatically by the function module REUSE_ALV_FIELDCATALOG_MERGE
vii. It_events : internal table with a list of all possible events of ALV and their corresponding form names.
II. Tables :
i. t_outtab : internal table with the data to be output
B. REUSE_ALV_FIELDCATALOG_MERGE : This function module is used to populate a fieldcatalog which is essential to display the data in ALV. If the output data is from a single dictionary table and all the columns are selected, then we need not exclusively create the field catalog. Its enough to mention the table name as a parameter(I_structure name) in the REUSE_ALV_LIST_DISPLAY. But in other cases we need to create it.
The Important Parameters are :
I. Export :
i. I_program_name : report id
ii. I_internal_tabname : the internal output table
iii. I_inclname : include or the report name where all the dynamic forms are handled.
II Changing
ct_fieldcat : an internal table
with the type SLIS_T_FIELDCAT_ALV which is declared in the type pool SLIS.
C. REUSE_ALV_EVENTS_GET : Returns table of possible events for a list type
Parameters :
I. Import :
Et_Events : The event table is returned with all possible CALLBACK events for the specified list type (column 'NAME'). For events to be processed by Callback, their 'FORM' field must be filled. If the field is initialized, the event is ignored. The entry can be read from the event table, the field 'FORM' filled and the entry modified using constants from the type pool SALV.
II. Export :
I_List_type :
0 = simple list REUSE_ALV_LIST_DISPLAY
1 = hierarchcal-sequential list REUSE_ALV_HIERSEQ_LIST_DISPLAY
2 = simple block list REUSE_ALV_BLOCK_LIST_APPEND
3 = hierarchical-sequential block list REUSE_ALV_BLOCK_LIST_HS_APPEND
D. REUSE_ALV_COMMENTARY_WRITE : This is used in the Top-of-page event to print the headings and other comments for the list.
Parameters :
I. it_list_commentary : internal table with the headings of the type slis_t_listheader.
This internal table has three fields :
Typ : ‘H’ – header, ‘S’ – selection , ‘A’ - action
Key : only when typ is ‘S’.
Info : the text to be printed
E. REUSE_ALV_GRID_DISPLAY : A new function in 4.6 version, to display the results in grid rather than as a preview.
Parameters : same as reuse_alv_list_display
This is an example for simple list.
