How to ijntroduce PUSH Button in KD_GET_FILENAME_ON_F4

Question

Dear Experts,
I am new to ABAP.
I know how to use push button in Sel-Screen. But my requirement is:
1)How can I use a push button in "KD_GET_FILENAME_ON_F4" so that on hitting the push button a PopUp screen appears.
2) This Pop up screen should be a file directory screen from which I can select a file.
3) This file on one click should get considered as "file_name" of the call function "KD_GET_FILENAME_ON_F4."
Looking forward for advise from experts.
Regards
Chandan Kumar

Answer 1

Dear Mr Klaus,
Thanks for your reply. The method suggested by you will definitely help the user to directly open a file dialogue box. But I want the code to make it more simpler for the user. After I execute the code The use should get a Push Button. On hitting this push button a POP UP screen should appear. This pop up screen should lear us to the target folder.
In your suggestion it was possible to open a folder path pop up screen. just I want to intriduce a PUSH button there. Also I want multi selection to be possible. In your suggestion above when I wrote the code as:
DATA: file_str1 type string.
data: it_tab TYPE STANDARD TABLE OF file_table,
      lw_file LIKE LINE OF it_tab,
      gd_subrc TYPE i.
SELECTION-SCREEN begin of block blk with frame title text-100.
SELECTION-SCREEN SKIP 2.
parameters : p_file like rlgrap-filename .
SELECTION-SCREEN end of block blk.
*F4 input file
AT SELECTION-SCREEN ON VALUE-REQUEST FOR p_file.
CALL METHOD cl_gui_frontend_services=>file_open_dialog
EXPORTING
window_title = 'Select only Text File'
default_filename = '.azt'
multiselection = 'X'
CHANGING
file_table = it_tab
rc = gd_subrc.
READ TABLE it_tab INTO lw_file INDEX 1.
p_file = lw_file-FILENAME.
Start-of-Selection.
  file_str1 = P_file.
CALL FUNCTION 'GUI_UPLOAD'
  EXPORTING
    filename                      = file_str1
*    filename                      = '\\10.10.1.92\Volume_1\_projekte\Zeiterfassung-SAP\test.azt'
  tables
    data_tab                      = it_string
IF sy-subrc <> 0.
* MESSAGE ID SY-MSGID TYPE SY-MSGTY NUMBER SY-MSGNO
*         WITH SY-MSGV1 SY-MSGV2 SY-MSGV3 SY-MSGV4.
ENDIF.
In the above code when I use Multiselection = 'X' then in the folder pop up multiselection is possible but the multiselection deosn't
gets selected for upload.
Looking forward for your suggestions.
That is my requirement.
Regards,
Chandan