How to sort a structure according to col_pos of field catalog table?

Is it possible that the X_FINAL-EINDT will be concatenated first instead of X_FINAL-WERKS? Is there a way to it without hard coding the field names?

DATA: begin of t_final,
   werks like ekpo-werks, 
   eindt like ekes-eindt, 
   uzeit like ekes-uzeit, 
   slfdt TYPE eket-slfdt, 
   ekgrp like ekko-ekgrp, 
   buyer(18) type c,
   mtart TYPE mara-mtart, 
   wrkst like mara-wrkst, 
   raube TYPE mara-raube, 
   tempb TYPE mara-tempb, 
   profl like mara-profl, 
   ebeln like ekko-ebeln, 
   ebelp like ekpo-ebelp, 
   matnr like ekpo-matnr, 
   maktx like makt-maktx, 
END of t_final. 

DATA: t_fieldcat TYPE slis_fieldcat_alv,
      x_final  LIKE LINE OF t_final.

IN T_FIELDCAT, the first column is EINDT

WHile in the T_FINAL and X_FINAL, the first column is WERKS.

Is it possible or useful to align the sorting orber of t_final from t_fieldcat?

The reason I'm asking because the X_FINAL is being used in a CONCATENATE code:

CONCATENATE
x_final2-werks x_final2-eindt x_final2-uzeit x_final2-ekgrp

Instead of WERKS being always the first to be concatenated, I want to concatenate the first field according to COL_POS from T_FIELDCAT.

Example:
T_FIELDCAT-FIELDNAME: EIDNT

T_FIELDCAT-COL_POS: 1

T_FIELDCAT-FIELDNAME: WERKS

T_FIELDCAT-COL_POS: 2

The problem with the code below is sometimes the EIDNT has a col_pos of 1 but sometimes it has a value of like 15. can I concatenate without hard coding?

CONCATENATE
X_FINAL-EIDNT X_FINAL-WERKS

You could sort the fieldcatalog by col_pos and loop over it. In the loop you assign the field in the structure t_final with the name from the fieldcatalog to a field-symbol and concatenate into the variable you need it to be in. Something like this:

field-symbols: <v_field> type any.
data: v_concat type string.

sort t_fieldcat by col_pos.
loop at t_fieldcat into s_fieldcat.
  assign component s_fieldcat-fieldname of structure t_final to <v_field>.
  if sy-subrc = 0.
    concatenate v_concat <v_field> into v_concat.
  endif.
endloop.

You might have to write the field-symbol into a charlike variable to get the concatenate to work properly all the time and also condense the results as needed.