F4 help for a dropdown field in ALV

Question

I am trying to enable F4 help for a field in ALV (OO style) that also has a dropdown assigned to it.
If I enable the dropdown in the field catalog, the field does not respond to F4 event at all.
When I remove the dropdown attribute from the field catalog, the F4 help works, but obviously now there is no dropdown.
The reason I am trying to implement it this way is that my dropdown list (which is the same for all rows) is quite large while F4 help depends on the current line in the ALV (so the available values are limited).
I would like to try to avoid creating a dropdown handle for every row in ALV.
Does anybody know if it's even possible to have a dropdown and F4 help at the same time in ALV?

Answer 1

Hi
Linking F4 Help to Fields
For the last section, we will deal with linking F4 help to fields. It is easy. As usual, define, implement and register the event “onf4” at proper places in your code. For F4 help, you must register the fields whose F4 request will trigger the “onf4” event. For this you must prepare a table of type “LVC_T_F4” and register this table using the method “register_f4_for_fields”. While preparing table you must include a line for each field which will trigger F4 event. For each field in the structure;
1) Pass the fieldname to ‘FIELDNAME’
2)Set ‘REGISTER’ to make the field registered,
3)Set ‘GETBEFORE’ to provide field content transport before F4 in editable mode
4)Set ‘CHNGEAFTER’ to make the data changed after F4 in editable mode.
Preparing table for the fields to be registered to trigger F4 event
DATA: lt_f4 TYPE lvc_t_f4 WITH HEADER LINE .
lt_f4-fieldname = 'PRICE'.
lt_f4-register = 'X' .
lt_f4-getbefore = 'X' .
APPEND lt_f4 .
CALL METHOD gr_alvgrid->register_f4_for_fields
EXPORTING
it_f4 = lt_f4[] .
A sample “onf4” method implementation
METHOD handle_on_f1 .
PERFORM f4_help USING e_fieldname es_row_no .
er_event_data->m_event_handled = 'X' .
ENDMETHOD .
Again, we set the attribute “er_event_data->m_event_handled” to prevent further processing of standard F4 help.
Check this link
http://help.sap.com/saphelp_nw04/helpdata/en/ed/ec623c4f69b712e10000000a114084/content.htm
Check these standard programs
BCALV_GRID_F4_HELP_APPLICATION
BCALV_GRID_F4_HELPM01
BCALV_TEST_GRID_F4_HELP
Regards
Pavan