ABAP-how to define a drop-down list in the alv_grid Function

Recently, I have heard from netizens and users that I want you to add a list to the ALV grid function. In fact, sap has already considered your needs and your needs can be fulfilled. I will dedicate the code for your reference and learning.

The Code is as follows:

Report.
**************************************** ********************************
* Daten definition *
**************************************** ********************************
Type-pools: slis.

Types:
Begin of t_data,
Matnr type Makt-matnr,
Maktx type Makt-maktx,
Spras type Makt-spras,
End of t_data,
Begin of t_alv,
Matnr type Makt-matnr,
Maktx type Makt-maktx,
Spras type Makt-spras,
Dd_handle type int4,
End of t_alv.
Data:
Gt_fieldcatalog type lvc_t_fcat,
Gw_fieldcatalog type lvc_s_fcat,
* Define data in the storage drop-down list
Gt_ddval type lvc_t_drop,
Gw_ddval type lvc_s_drop,

Gt_events type slis_t_event,
Gw_events type slis_alv_event,
Gt_data type table of t_data,
Gw_data type t_data,
Gt_alv type table of t_alv,
Gw_alv type t_alv,
G_repid type sy-repid value sy-repid.
**************************************** ********************************
* Selection screen *
**************************************** ********************************
Select-options: s_matnr for gw_data-matnr.

**************************************** ********************************
* Start-of-selection *
**************************************** ********************************
Start-of-selection.
Select matnr maktx spras
Into Table gt_data up to 50 rows
From Makt
Where matnr in s_matnr
And spras = 'en '.

Loop at gt_data into gw_data.
Move-corresponding gw_data to gw_alv.
Append gw_alv to gt_alv.
Endloop.

Perform creat_fieldcat.
Perform creat_dropdown_values.
Perform creat_event_exits.
Call function 'reuse _ alv_grid_display_lvc'
Exporting
I _callback_program = g_repid
It_fieldcat_lvc = gt_fieldcatalog
It_events = gt_events
Tables
T_outtab = gt_alv.
*---------------------------------------------------------------------*
* Set the format of the output field
*---------------------------------------------------------------------*
Form creat_fieldcat.
Clear gw_fieldcatalog.
Gw_fieldcatalog-fieldname = 'matnr '.
Gw_fieldcatalog-ref_field = 'matnr '.
Gw_fieldcatalog-ref_table = 'makt '.
Append gw_fieldcatalog to gt_fieldcatalog.

Clear gw_fieldcatalog.
Gw_fieldcatalog-fieldname = 'maktx '.
Gw_fieldcatalog-ref_field = 'maktx '.
Gw_fieldcatalog-ref_table = 'makt '.
Append gw_fieldcatalog to gt_fieldcatalog.

Clear gw_fieldcatalog.
Gw_fieldcatalog-fieldname = 'spras '.
Gw_fieldcatalog-OUTPUTLEN = '7 '.
Gw_fieldcatalog-dd_outlen = '7 '.
Gw_fieldcatalog-intlen = '2 '.
Gw_fieldcatalog-inttype = 'C '.
Gw_fieldcatalog-coltext = 'language '.
Gw_fieldcatalog-tooltip = 'language '.
Gw_fieldcatalog-seltext = 'language '.
Gw_fieldcatalog-drdn_field = 'dd _ handle '.
Gw_fieldcatalog-EDIT = 'x '.
Append gw_fieldcatalog to gt_fieldcatalog.
Endform. "creat_fieldcat
*---------------------------------------------------------------------*
* Generate different drop-down lists based on all the languages of the materials.
*---------------------------------------------------------------------*
Form creat_dropdown_values.
Data: l_spras type Makt-spras,
Rochelle count type I.
Loop at gt_alv into gw_alv.
Add 1 to l_count.
Select spras
Into l_spras
From Makt
Where matnr = gw_alv-matnr.
Clear gw_ddval.
Gw_ddval-handle = l_count.
Gw_ddval-value = l_spras.
Append gw_ddval to gt_ddval.
Endselect.

Clear gw_ddval.
Gw_ddval-handle = l_count.
Gw_ddval-value = ''.
Append gw_ddval to gt_ddval.
* Set the corresponding
Gw_alv-dd_handle = l_count.
Modify gt_alv from gw_alv.
Endloop.
Endform. "creat_dropdown_values
*---------------------------------------------------------------------*
* Form creat_event_exits
*---------------------------------------------------------------------*
Form creat_event_exits.
Gw_events-name = 'caller _ exit '.
Gw_events-form = 'caller _ exit '.
Append gw_events to gt_events.
Endform. "creat_event_exits
*---------------------------------------------------------------------*
* Set the drop-down list so that the grid and internal tables can be linked.
*---------------------------------------------------------------------*
Form caller_exit using ls_data type slis_data_caller_exit.
Data: l_ref_alv type ref to cl_gui_alv_grid.
Call function 'get _ globals_from_slvc_fullscr'
Importing
E_grid = l_ref_alv.
Call method l_ref_alv-> set_drop_down_table
Exporting
It_drop_down = gt_ddval.
Endform. "caller_exit