Multi Level Tree ALV with CL_GUI_SIMPLE_TREE

DATA : lr_cust TYPE REF TO cl_gui_custom_container,
lr_tree TYPE REF TO cl_gui_simple_tree,
lt_scarr TYPE TABLE OF scarr,
ls_scarr TYPE scarr,
lt_spfli TYPE TABLE OF spfli,
ls_spfli TYPE spfli,
lt_node TYPE TABLE OF mtreesnode,
ls_node TYPE mtreesnode.

START-OF-SELECTION.
CALL SCREEN 0001.
*&———————————————————————*
*& Module STATUS_0001 OUTPUT
*&———————————————————————*

MODULE status_0001 OUTPUT.
SET PF-STATUS ‘STATUS’.
*  SET TITLEBAR ‘xxx’.
ENDMODULE.                 ” STATUS_0001  OUTPUT
*&———————————————————————*
*&      Module  GET_DATA  OUTPUT
*&———————————————————————*
MODULE get_data OUTPUT.
IF lt_scarr IS INITIAL.
SELECT * FROM scarr INTO TABLE lt_scarr.
IF lt_scarr IS NOT INITIAL.
SELECT * FROM spfli INTO TABLE lt_spfli FOR ALL ENTRIES IN lt_scarr WHERE carrid = lt_scarr–carrid.
ENDIF.
ENDIF.
ENDMODULE.                 ” GET_DATA  OUTPUT
*&———————————————————————*
*&      Module  BUILD_TREE  OUTPUT
*&———————————————————————*
MODULE build_tree OUTPUT.
IF lr_cust IS NOT BOUND.
CREATE OBJECT lr_cust
EXPORTING
container_name              = ‘SIMPLE_TREE’
repid                       = sy–repid
dynnr                       = sy–dynnr
EXCEPTIONS
cntl_error                  = 1
cntl_system_error           = 2
create_error                = 3
lifetime_error              = 4
lifetime_dynpro_dynpro_link = 5
OTHERS                      = 6.

ENDIF.
IF lr_tree IS NOT BOUND.
CREATE OBJECT lr_tree
EXPORTING
parent                      = lr_cust
node_selection_mode         = cl_gui_simple_tree=>node_sel_mode_single
EXCEPTIONS
lifetime_error              = 1
cntl_system_error           = 2
create_error                = 3
failed                      = 4
illegal_node_selection_mode = 5
OTHERS                      = 6.
ENDIF.

IF lr_tree IS BOUND.
CLEAR ls_node.
ls_node–node_key = ‘ROOT’.
ls_node–isfolder = ‘X’.
ls_node–text = ‘Flight Info’.
APPEND ls_node TO lt_node.
LOOP AT lt_scarr INTO ls_scarr.
CLEAR ls_node.
ls_node–node_key = ls_scarr–carrid.
ls_node–relatkey = ‘ROOT’.
ls_node–relatship = cl_gui_simple_tree=>relat_last_child.
ls_node–isfolder = ‘X’.
ls_node–n_image = ‘@7T@’. “ICON_WS_PLANE
ls_node–text = ls_scarr–carrname.
APPEND ls_node TO lt_node.

LOOP AT lt_spfli INTO ls_spfli WHERE carrid = ls_scarr–carrid.
CLEAR ls_node.
ls_node–node_key = ls_spfli–connid.
ls_node–relatkey = ls_scarr–carrid.
ls_node–relatship = cl_gui_simple_tree=>relat_last_child.
ls_node–isfolder = ‘ ‘.
ls_node–n_image = ‘@7T@’. “ICON_WS_PLANE
CONCATENATE ls_spfli–countryfr
‘ – ‘ ls_spfli–cityfrom
‘ – ‘ ls_spfli–countryto
‘ – ‘ ls_spfli–cityto INTO ls_node–text SEPARATED BY space.
APPEND ls_node TO lt_node.
ENDLOOP.
ENDLOOP.

CALL METHOD lr_tree->add_nodes
EXPORTING
table_structure_name           = ‘SCARR’
node_table                     = lt_node
EXCEPTIONS
error_in_node_table            = 1
failed                         = 2
dp_error                       = 3
table_structure_name_not_found = 4
OTHERS                         = 5.
ENDIF.

ENDMODULE.                 ” BUILD_TREE  OUTPUT
*&———————————————————————*
*&      Module  USER_COMMAND_0001  INPUT
*&———————————————————————*
MODULE user_command_0001 INPUT.
CASE sy–ucomm.
WHEN ‘BACK’ OR ‘EXIT’ OR ‘CANCEL’.
LEAVE TO SCREEN 0.
ENDCASE.
ENDMODULE.                 ” USER_COMMAND_0001  INPUT