How do I get my data to show up in my ALV? - abap

Question

I'm thinking that I'm probably missing an export parameter (from my Function Call POV).
In the REUSE_ALV_GRID_DISPLAY function call, the parameters I pass around are:
Exporting:
i_callback_program,
i_callback_pf_status_set,
i_callback_user_command,
is_layout,
it_fieldcat,
i_save
Tables:
t_outtab
And the exceptions plus handling.
I've checked that the internal table that I pass has data and it does.
I think the information I put up will suffice but if you really need to see the code, I'll do so.
I'm a noob and any help would be appreciated.
Thanx.

Answer 1

There are several ways to use ALV, so we may indeed need more info on your code to help.
First Method is to use the function module REUSE_ALV_GRID_DISPLAY. This will directly display the table content in the output dynpro. If all you need is a display, then go for it, as this is the simpliest : If the table structure is in the dictionnary, this call can be as simple as the following (this will display all members of the struct as column)
myreport = sy-repid.
CALL FUNCTION 'REUSE_ALV_GRID_DISPLAY'
EXPORTING
i_callback_program = myreport
it_excluding = exclude_tab
TABLES
t_outtab = display_data
EXCEPTIONS
program_error = 1
OTHERS = 2.
If the structure is declared in the program, then you have to create a field catalog.
the following code can serve as basis :
FORM fill_fieldcat CHANGING p_fieldcat TYPE slis_t_fieldcat_alv.
* Data definition
DATA ls_fieldcat TYPE slis_fieldcat_alv.
* Macro definition
DEFINE append_fieldcat.
clear ls_fieldcat.
ls_fieldcat-fieldname = &1. * name of the field in struct
ls_fieldcat-tabname = &2. * name of the table
ls_fieldcat-row_pos = &3. * column
ls_fieldcat-ref_fieldname = &4. * field in ref table
ls_fieldcat-ref_tabname = &5. * ref table
ls_fieldcat-outputlen = &6. * size of output
ls_fieldcat-seltext_m = &7. * text (space if using the element typetext)
ls_fieldcat-ddictxt = 'M'.
ls_fieldcat-key = &8. * is this a key field in table
ls_fieldcat-emphasize = &9. * emphisze column display
append ls_fieldcat to p_fieldcat.
END-OF-DEFINITION.
* Init.
REFRESH p_fieldcat.
* Append fielcatalog for ALV
append_fieldcat:
'FORMATIONCODE' 'DISPLAY_TAB' 1 'SHORT' 'HRP1000' 12 'Code Stage' space space,
'FORMATIONTEXT' 'DISPLAY_TAB' 1 'STEXT' 'HRP1000' 20 'Libelle Stage' space space,
'SESSIONID' 'DISPLAY_TAB' 1 'OBJID' 'HRP1000' space 'Session' space space,
'BEGDA' 'DISPLAY_TAB' 1 'BEGDA' 'HRP1000' space 'Debut' space space,
'ENDDA' 'DISPLAY_TAB' 1 'BEGDA' 'HRP1000' space 'Fin' space space,
ENDFORM. "fill_fieldCat
you then call the form to create the field catalog, and use it in the it_fieldcat parameter of the function call.
Second method is to use ABAP-Object. Use check se83 for exemples of this use. the basis is as follows :
In your Dynpro you declare a custom container with a given name ("ALV_CONT"). Then in then PBO of the dynpro you initialize the container and put an ALV objct inside :
* global variables :
DATA : delegationlist_table TYPE REF TO cl_gui_alv_grid,
delegationlist_container TYPE REF TO cl_gui_custom_container.
data : gs_layout TYPE lvc_s_layo.
in PBO
IF delegationlist_container IS INITIAL.
* create a custom container control for our ALV Control
CREATE OBJECT delegationlist_container
EXPORTING
container_name = 'ALV_CONT'
EXCEPTIONS
cntl_error = 1
cntl_system_error = 2
create_error = 3
lifetime_error = 4
lifetime_dynpro_dynpro_link = 5.
* create an instance of alv control
CREATE OBJECT delegationlist_table
EXPORTING
i_parent = delegationlist_container.
* Set a titlebar for the grid control
gs_layout-grid_title = 'Délégations'.
gs_layout-sel_mode = 'A'.
gs_layout-cwidth_opt ='X'.
* set table as data source
* the struct name *must* be uppercase
* the table must have this struc
CALL METHOD delegationlist_table->set_table_for_first_display
EXPORTING
i_structure_name = 'ZPRT_DELEGATIONLIST'
is_layout = gs_layout
CHANGING
it_outtab = delegationlist.
ENDIF.
Hopes this help,
Regards
Guillaume PATRY

Answer 2

EDIT: Oh, and another thing - if you're really in POV (process on Value-Request = F4), be aware that there are limitations to what you can do. Try your code in a simple report right after START-OF-SELECTION, and if that works, try the same code in a POV module.
===
If you don't pass a structure name, you have to ensure that you pass a complete (!) field catalog, otherwise the ALV grid might start to work erratically or not at all. Use the function modules LVC_FIELDCATALOG_MERGE and LVC_FIELDCAT_COMPLETE (in this order) to get a LVC field catalog that can be used with the classes or REUSE_ALV_GRID_DISPLAY_LVC.

Answer 3

A couple people here suggested using the REUSE_ALV_GRID_DISPLAY. I'm sure this is a common way to get things done (I used to use it myself), but I've taken a sap delta course recently and they strongly suggested to not use it anymore (you can look it up, REUSE_ALV_GRID_DISPLAY is not officialy supported by SAP anymore).
Instead, use CL_SALV_TABLE, documentation here: http://help.sap.com/erp2005_ehp_04/helpdata/EN/d7/b22041aa7df323e10000000a155106/frameset.htm
It's actually rather convenient to use too.

Answer 4

Thanks for the effort but as it turned out, the mistake I did was that I didn't capitalize field names in building the Field Catalog. Such a newbie mistake. I guess I won't be doing that mistake again any time soon.
-migs

Answer 5

Pass the output internal table to the FM Parameter "t_outtab".
It will print your data output.