Control Framework: Fatal error - GUI cannot be reached-ALV Grid in Bckgrnd

Question

I have an ALV grid which dumps in the background. But works fine in the foreground.
I thought I am not using Control framework anywhere. But I get 'COntrol framework :Fatal error - GU cannot be reached' error.
I am using a docking container that I have split using a splitter.
I have no custom container in my screen. What else could be causing the Control framework error ? Any suggestions is appreciated. But please do not tell me to use 'REUSE_ALV*' or Classical reporting
Here are the PBO modules of my screen and here are my data declarations.
ALV Data declarations :
data :gt_sort type lvc_t_sort,
        gr_event_handler TYPE REF TO lcl_event_handler ,
     o_docking type ref to cl_gui_docking_container,"Docking Container
     o_grid type ref to cl_gui_alv_grid,"Grid
     o_split type ref to cl_gui_easy_splitter_container,"Splitter
     o_top_container type ref to cl_gui_container,   "Top Container
     o_bottom_container type ref to cl_gui_container,"Bottom Container
     o_document type ref to cl_dd_document.          "Document
module status_0100 output.
if o_docking is initial.
  set pf-status 'ZSTATUS_0100'.
  set titlebar 'ZTITLE_0100'.
Creating Objects
  perform create_objects.
Filling top of page
  perform fill_top_of_page.
Filling the fieldcatalog table
perform build_fieldcat. "we already got'em
Displaying the output
  perform display_output.
endif.
Here is the Form Create_objects called in the PBO.
form create_objects .
Creating Docking Container
  CREATE OBJECT o_docking
         EXPORTING
           RATIO                       = '95'.
  IF sy-subrc eq 0.
Splitting the Docking container
    CREATE OBJECT o_split
      EXPORTING
       PARENT            = o_docking
       sash_position     = 25 "Position of Splitter Bar (in Percent)
       with_border       = 0. "With Border = 1 Without Border = 0
  Placing the containers in the splitter
    o_top_container = o_split->top_left_container .
    o_bottom_container = o_split->bottom_right_container .
  Creating Grid
    CREATE OBJECT o_grid
      EXPORTING
        i_parent          =  o_bottom_container.
  Creating the document
    CREATE OBJECT o_document
    EXPORTING
        style  = 'ALV_GRID'.
     CREATE OBJECT gr_event_handler .
  ENDIF.
endform.                    " create_objects
form fill_top_of_page .
data : lv_char(255) type c.
Calling the methods for dynamic text
   CALL METHOD o_document->add_gap
    EXPORTING
      width      = 140.
  CALL METHOD o_document->add_text
    EXPORTING
      text          = 'Plant Attainment Report '
      sap_fontsize  = 'Large'
      sap_color     = cl_dd_area=>list_key_int
      sap_emphasis  = cl_dd_area=>strong. " For bold
Display the data
  CALL METHOD o_document->display_document
    EXPORTING
       parent             = o_top_container.
Calling the method of ALV to process top of page
  CALL METHOD o_grid->list_processing_events
    EXPORTING
      i_event_name      = 'TOP_OF_PAGE'
      i_dyndoc_id       = o_document.
endform.                    " fill_top_of_page
form display_output .
  gx_variant-report = sy-repid.
  gs_layout-zebra = 'X'.
  gs_layout-sel_mode ='X'.
  gs_layout-cwidth_opt = 'X'.
  call method o_grid->set_table_for_first_display
    exporting
      is_variant      = gx_variant
      i_save          = 'A'
      is_layout       = gs_layout
    changing
      it_fieldcatalog = it_fldcat
      it_outtab       = <gt_tabletotal>.
    IF sy-subrc <> 0.
       MESSAGE ID SY-MSGID TYPE SY-MSGTY NUMBER SY-MSGNO
                   WITH SY-MSGV1 SY-MSGV2 SY-MSGV3 SY-MSGV4.
    ENDIF.
    SET HANDLER gr_event_handler->handle_print_top_of_page FOR o_grid .
endform.                    " display_output 
Edited by: Shareen Hegde on Jul 23, 2009 5:03 PM (I have no clue why 
.. doesn't work anymore. My code looks messed up..Sorry folks!

Answer 1

Nilesh,
If i put all these create objects inside the      IF CL_GUI_ALV_GRID=>OFFLINE( ) IS INITIAL.   ENDIF , will I be still able to use ,
call method o_grid->set_table_for_first_display
    exporting
      is_variant      = gx_variant
      i_save          = 'A'
      is_layout       = gs_layout
    changing
      it_fieldcatalog = it_fldcat
      it_outtab       = <gt_tabletotal>.
     in background ? WIll I not get - OBJECTS_OBJREF_NOT_ASSIGNED   erorr ?
How can I call the set_table_for_first_display without creating the object reference ?
Here is my creat object routine.
form create_objects .
* Creating Docking Container
IF CL_GUI_ALV_GRID=>OFFLINE( ) .
  CREATE OBJECT o_docking
         EXPORTING
           RATIO                       = '95'.
  IF sy-subrc eq 0.
* Splitting the Docking container
    CREATE OBJECT o_split
      EXPORTING
       PARENT            = o_docking
       sash_position     = 25 "Position of Splitter Bar (in Percent)
       with_border       = 0. "With Border = 1 Without Border = 0
*   Placing the containers in the splitter
    o_top_container = o_split->top_left_container .
    o_bottom_container = o_split->bottom_right_container .
*   Creating Grid
    CREATE OBJECT o_grid
      EXPORTING
        i_parent          =  o_bottom_container.
*   Creating the document
    CREATE OBJECT o_document
    EXPORTING
        style  = 'ALV_GRID'.
     ENDIF.
     CREATE OBJECT gr_event_handler .
endif.
endform.                    " create_objects