MODULE init_tree OUTPUT.

  IF g_tree IS INITIAL.
    DATA: node_table TYPE node_table_type.
    DATA : events TYPE cntl_simple_events,
           event TYPE cntl_simple_event.
    CREATE OBJECT tree_con_ref
      EXPORTING        " the container is linked to the custom control with the
              " name 'TREE_CONTAINER' on the dynpro
        container_name = 'TREE_CONTAINER'.
* create a tree control
    CREATE OBJECT g_tree
      EXPORTING
        parent              = tree_con_ref
        node_selection_mode = cl_gui_simple_tree=>node_sel_mode_single.        " single node selection is used

    PERFORM build_node_table USING node_table.
* node_table_structure_name     = 'MTREESNODE'
    CALL METHOD g_tree->add_nodes
      EXPORTING
        table_structure_name = 'MTREESNODE'
        node_table           = node_table.

    CREATE OBJECT g_application.

* define the events which will be passed to the backend
    " node double click
    event-eventid = cl_gui_simple_tree=>eventid_node_double_click.
    event-appl_event = 'X'. " process PAI if event occurs
    APPEND event TO events.

    CALL METHOD g_tree->set_registered_events
      EXPORTING
        events                    = events
      EXCEPTIONS
        cntl_error                = 1
        cntl_system_error         = 2
        illegal_event_combination = 3.

* assign event handlers in the application class to each desired event
    SET HANDLER g_application->handle_node_double_click FOR g_tree.

  ENDIF.

ENDMODULE.                 " init_tree  OUTPUT

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