User input in ALV Grid

Question

Hello All,
Is it possible to have a user input in ALV grid. I know there can be editable columns/cells but suppose the application demands an input field to be placed in ALV Grid where the user will enter some value.
Could someone please suggest if this can be done.
Regards
Indrajit

Answer 1

Here's THE definitive way to do it.
This little proggy demonstrates the following.
1) Create a DYNAMIC FCAT for an internal table with USER defined fields (i.e non ddic) and colour some columns in the FCAT.
2) Create a DYNAMIC TABLE.
3) Define a subclass of CL_GUI_ALV_GRID so you can access some very useful protected methods and attributes - you can get original and changed table IN ROWS which is a lot easier sometimes than messing around with individual
cells.
4) Create extra buttons on the toolbar.
5) Define EVENT handlers including data change so you can get control when the user enters data. YOU DON'T NEED PAI anymore with event handlers.
6) Call methods in your subclass of CL_GUI_ALV_GRID (you can also call methods in CL_GUI_ALV_GRID by virtue of Inheritance) from methods in your event handler class.
7) Display an editable Grid.
This method will work for almost any conditions you need to use.
I'm sure this covers all the bases -- please reply if any queries.
Run the program, click on the EDIT button and enter your data. Press ENTER when done.
All you need to do is copy this code and create one empty screen (SE51) with a custom container called CCONTAINER1  with the following logic in it.
PROCESS BEFORE OUTPUT.
MODULE STATUS_0100.
PROCESS AFTER INPUT.
MODULE USER_COMMAND_0100.
(In the program you don't actually do anything in the PAI as the event handler takes care of this)
Now here's the program
PROGRAM zdynfieldcat.
class zcltest definition  deferred.  "For field symbol reference.
Simple test of dynamic ITAB with user defined (not ddic) fields
Build dynamic fcat
Table structure obtained via new RTTI functionality
use ALV grid to display and edit.
Create a blank screen 100 with a custom container called CCONTAINER1.
Define field symbols as these can't be defined in classes
field-symbols: <dyn_table> type standard table,
               <g2> type ref to zcltest,
               <g1> type ref to cl_gui_custom_container,
               <actual_tab> type standard table,
               <outtab> type table,
               <fs1> type ANY,
               <FS2> TYPE TABLE,
               <fs3> type table,
               <fs4> type table,
               <fs5> type  table.
class zcltest definition inheriting from cl_gui_alv_grid.
define this as a subclass so we can access the protected attributes
of the superclass cl_gui_alv_grid
  public section.
    types:  g4 type ref to cl_gui_custom_container.
    types:  g3  type ref to cl_alv_changed_data_protocol.
    data:   i_parent type g4,
            lr_rtti_struc TYPE REF TO cl_abap_structdescr, "RTTI
    zog like line of lr_rtti_struc->components. "RTTI
    types: struc like zog.
    types: struc1 type table of struc.
    methods:
       constructor
           importing i_parent type g4,
       disp_tab
           importing  p_er_data_changed type g3,
       create_dynamic_fcat
           importing zogt type struc1
           exporting it_fldcat type lvc_t_fcat.
Protected section.
   data: stab type ref to data,
        wa_it_fldcat type lvc_s_fcat,
        c_index type sy-index.
endclass.
class zcltest implementation.
  METHOD constructor.
    CALL METHOD super->constructor
      EXPORTING
        i_appl_events = 'X'
        i_parent      = i_parent.
      endmethod.
  method disp_tab.
mt_outtab is the data table held as a protected
attribute in class cl_gui_alv_grid.
    assign me->mt_outtab->* TO <outtab>. "Original data
    assign p_er_data_changed->mp_mod_rows TO <FS1>.
    stab = p_er_data_changed->mp_mod_rows.
    assign p_er_data_changed->mt_inserted_rows to <fs3>.
    assign p_er_data_changed->mt_deleted_rows to <fs4>.
    assign p_er_data_changed->mt_mod_cells to <fs5>.
    assign stab->* TO <fs2>.
do whatever you want with <outtab>
contains data BEFORE changes each time.
Note that NEW (Changed) table has been obtained
already by  call to form
check_data USING P_ER_DATA_CHANGED
TYPE REF TO CL_ALV_CHANGED_DATA_PROTOCOL.
Entered data is in table defined by <fs2>
In this method you can compare original and changed data.
Easier than messing around with individual cells.
do what you want with data in <fs2> validate / update / merge etc
  endmethod.
  method create_dynamic_fcat.
    loop at zogt into zog.
      c_index = c_index + 1.
      clear wa_it_fldcat.
      wa_it_fldcat-fieldname = zog-name .
      wa_it_fldcat-datatype = zog-type_kind.
      wa_it_fldcat-inttype = zog-type_kind.
      wa_it_fldcat-intlen = zog-length.
      wa_it_fldcat-decimals = zog-decimals.
      wa_it_fldcat-coltext = zog-name.
      wa_it_fldcat-lowercase = 'X'.
      if c_index eq 2.
        wa_it_fldcat-emphasize = 'C411'.
      endif.
      if c_index eq 3.
        wa_it_fldcat-emphasize = 'C511'.
      endif.
      append wa_it_fldcat to it_fldcat .
    endloop.
  endmethod.                    "create_dynamic_fcat
endclass.                    "zcltest IMPLEMENTATION
class lcl_grid_event_receiver definition.
  public section.
note that zcltest inherits all of events etc from
class cl_gui_alv_grid so specify event handler for
zcltest.
methods:
    handle_data_changed
         for event data_changed of zcltest
         importing  er_data_changed,
    toolbar
         for event toolbar of zcltest
         importing e_object
         e_interactive,
    user_command
         for event user_command of zcltest
         importing e_ucomm.
endclass.
class lcl_grid_event_receiver implementation.
  method handle_data_changed.
code whatever required after data entry.
various possibilites here as you
can get back Cell(s) changed
columns or the entire updated table.
Data validation is also possible here.
Note here the field sybol <g2> contains our
instance of  class zcltest so we can now
call any methods / access
attributes of that class from this method
in our event handler class.
    call method <g2>->disp_tab
      EXPORTING
        p_er_data_changed = er_data_changed.
  endmethod.                    "handle_data_changed
  method toolbar.
    data : ls_toolbar type stb_button.
    clear ls_toolbar.
    move 0 to ls_toolbar-butn_type.
    move 'EDIT' to ls_toolbar-function.
    move space to ls_toolbar-disabled.
    move 'Edit' to ls_toolbar-text.
    move icon_change_text to ls_toolbar-icon.
    move 'Click2Edit' to ls_toolbar-quickinfo.
    append ls_toolbar to e_object->mt_toolbar.
    clear ls_toolbar.
    move 0 to ls_toolbar-butn_type.
    move 'UPDA' to ls_toolbar-function.
    move space to ls_toolbar-disabled.
    move 'Update' to ls_toolbar-text.
    move icon_system_save to ls_toolbar-icon.
    move 'Click2Update' to ls_toolbar-quickinfo.
    append ls_toolbar to e_object->mt_toolbar.
    clear ls_toolbar.
    move 0 to ls_toolbar-butn_type.
    move 'EXIT' to ls_toolbar-function.
    move space to ls_toolbar-disabled.
    move 'Exit' to ls_toolbar-text.
    move icon_system_end to ls_toolbar-icon.
    move 'Click2Exit' to ls_toolbar-quickinfo.
    append ls_toolbar to e_object->mt_toolbar.
  endmethod.                    "toolbar
  method user_command.
    case e_ucomm .
      when 'EDIT'. "From Tool bar
        perform set_input.
        perform init_grid.
      when 'UPDA'. "From Tool bar
        perform refresh_disp.
        perform update_table.
      when 'EXIT'. "From Tool bar
        leave program.
    endcase.
  endmethod.                    "user_command
endclass.                    "lcl_grid_event_receiver IMPLEMENTATION
program data
include <icon>.
define any old internal structure NOT in DDIC
types: begin of s_elements,
anyfield1(20) type c,
anyfield2(20) type c,
anyfield3(20) type c,
anyfield4(20) type c,
anyfield5(11) type n,
end of s_elements.
data: wa_element type s_elements,
wa_data type s_elements.
Note new RTTI functionality allows field detail
retrieval at runtime for dynamic tables.
data:
        grid1 type ref to zcltest,
        grid_handler type ref to lcl_grid_event_receiver,
        c_dec2 type s_elements-anyfield5,
        wa_it_fldcat type lvc_s_fcat,
        it_fldcat type lvc_t_fcat,
        lr_rtti_struc TYPE REF TO cl_abap_structdescr, "RTTI
        lt_comp TYPE cl_abap_structdescr=>component_table,"RTTI
        ls_comp LIKE LINE OF lt_comp, "RTTI
        zog like line of lr_rtti_struc->components,  "RTTI
        struct_grid_lset type lvc_s_layo,
        l_valid type c,
        new_table type ref to data.
        types: struc like zog.
data:  zogt type table of struc,
        grid_container1 type ref to cl_gui_custom_container,
        g_event_receiver type ref to lcl_grid_event_receiver,
        ok_code like sy-ucomm,
        i4 type int4.
start-of-selection.
  call screen 100.
module status_0100 output.
  if grid_container1 is initial.
    create object grid_container1
    exporting
    container_name = 'CCONTAINER1'.
    assign grid_container1 to <g1>.
    create object grid1
     exporting i_parent = grid_container1.
we need reference to this instance so we can use
Methods etc of zcltest class and alv (superclass)
in our event receiver class.
     assign grid1 to <g2>.
    create object grid_handler.
    set handler:
    grid_handler->user_command for grid1,
    grid_handler->toolbar for grid1,
    grid_handler->handle_data_changed for grid1.
Get the Internal table structure
    lr_rtti_struc ?= cl_abap_structdescr=>describe_by_data( wa_data ).
Build field catalog just use basic data here
colour specific columns as well
    zogt[] = lr_rtti_struc->components.
       call method grid1->create_dynamic_fcat
      EXPORTING
        zogt      = zogt
      IMPORTING
        it_fldcat = it_fldcat.
Create dynamic internal table and assign
to field symbol.
Use dynamic field catalog just built.
  call method cl_alv_table_create=>create_dynamic_table
    EXPORTING
      it_fieldcatalog = it_fldcat
    IMPORTING
      ep_table        = new_table.
  assign new_table->* to <dyn_table>.
    perform populate_dynamic_itab.
    perform init_grid.
    perform register_enter_event.
set off ready for input initially
    i4 = 0.
    call method grid1->set_ready_for_input
      EXPORTING
        i_ready_for_input = i4.
  endif.
endmodule.                    "status_0100 OUTPUT
module user_command_0100 input.
*PAI not needed in OO ALV anymore as User Commands
are handled as events
*in method user_command.
we can also get control if any data was entered
and the ENTER is pressed by
raising an event.
Control then returns to method handle_data_changed.
endmodule.                    "user_command_0100 INPUT
form populate_dynamic_itab.
load up a line of the dynamic table
  c_dec2 = c_dec2 + 11.
  wa_element-anyfield1 = 'Tabbies'.
  wa_element-anyfield2 = 'ger.shepards'.
  wa_element-anyfield3 = 'White mice'.
  wa_element-anyfield4 = 'Any old text'.
  wa_element-anyfield5 = c_dec2.
  append wa_element to <dyn_table>.
endform.                    "populate_dynamic_itab
form exit_program.
  call method grid_container1->free.
  call method cl_gui_cfw=>flush.
  leave program.
endform.                    "exit_program
form refresh_disp.
  call method grid1->refresh_table_display.
endform.                    "refresh_disp
form update_table.
The dynamic table here is the changed table
read from the grid
after user has changed it
Data can be saved to DB or whatever.
  loop at <dyn_table> into wa_element.
do what you want with the data here
  endloop.
switch off edit mode again for next function
  i4 = 0.
  call method grid1->set_ready_for_input
    EXPORTING
      i_ready_for_input = i4.
endform.                    "update_table
form set_input.
  i4 = 1.
  call method grid1->set_ready_for_input
    EXPORTING
      i_ready_for_input = i4.
endform.                    "set_input
form switch_input.
  if i4 = 1.
    i4 = 0.
  else.
    i4 = 1.
  endif.
  call method grid1->set_ready_for_input
    EXPORTING
      i_ready_for_input = i4.
endform.                    "switch_input
form init_grid.
Enabling the grid to edit mode,
  struct_grid_lset-edit = 'X'. "To enable editing in ALV
  struct_grid_lset-grid_title = 'Jimbos Test'.
   call method grid1->set_table_for_first_display
    EXPORTING
      is_layout       = struct_grid_lset
    CHANGING
      it_outtab       = <dyn_table>
      it_fieldcatalog = it_fldcat.
endform.                    "init_grid
form register_enter_event.
  call method grid1->register_edit_event
    EXPORTING
      i_event_id = cl_gui_alv_grid=>mc_evt_enter.
Instantiate the event or it won't work.
  create object g_event_receiver.
  set handler g_event_receiver->handle_data_changed for grid1.
endform.                    "register_enter_event
Have fun with this
Cheers
jimbo