How to get data from a dynamic node in Webdynpro ABAP ?

Hi,

I have come across many scn threads which refer to "How to read / get data from a dynamic node" .

Here I would like to demonstrate, the steps to read the data from a node ( either static / dynamic node ) in Webdynpro ABAP.

I have divided the task into 3 methods

1. GET_NODE_INFO( ) - Get node information from node name
2. GET_NODE_DATA_TYPE( ) - Get node data type & attribute list by using node reference ( if_wd_context_node )
3. GET_DATA( ) - Get data of any given node reference

Now, let us look into the code of each method as below

GET_NODE_INFO( )

Parameters:

Logic:

METHOD get_node_info .
  DATA:    lo_node_info    TYPE REF TO if_wd_context_node_info,
           lo_parent_node  TYPE REF TO if_wd_context_node,
           lv_node_name    TYPE string,
           lx_root         TYPE REF TO cx_root.

  TRY.
      "=============================================
      " check if node name is supplied,
      " if so nothing do , return the control
      "=============================================
      IF id_node_name IS INITIAL.
        RETURN.
      ELSE.
        lv_node_name = id_node_name.
        TRANSLATE lv_node_name TO UPPER CASE.
      ENDIF.

      "=============================================
      " Check if io_parent_node is not bound, if so
      " Assume parent node is WD_CONTEXT
      "=============================================
      IF io_parent_node IS NOT BOUND.
        lo_parent_node = wd_context.
      ELSE.
        lo_parent_node = io_parent_node.
      ENDIF.

      "=============================================
      "get node info
      "=============================================
      eo_node = lo_parent_node->get_child_node( name = lv_node_name ).

      eo_node_info = eo_node->get_node_info( ).

    CATCH cx_root INTO lx_root.
      ed_error_message = lx_root->get_text( ).
  ENDTRY.
ENDMETHOD.

----------------------------------------------------------

GET_NODE_DATA_TYPE( )

Parameters:

Logic:

METHOD GET_NODE_DATA_TYPE .
  CLEAR:
      eo_data,
      et_fcat,
      ed_error_message.
  TRY .

      DATA:
            lo_table        TYPE REF TO data,
            ls_fcat         TYPE lvc_s_fcat,
            lt_attr         TYPE wdr_context_attr_info_map,
            ls_attr         LIKE LINE OF lt_attr,
            lx_root         TYPE REF TO cx_root.

      IF io_node_info IS NOT BOUND.
        ed_error_message = 'Node info is invalid'.
        RETURN.

      ENDIF.

      "=============================================
      " get attributes
      "=============================================
      lt_attr = io_node_info->get_attributes( ).

      LOOP AT lt_attr INTO ls_attr.
        CLEAR ls_fcat.
        ls_fcat-fieldname = ls_attr-name.
        ls_fcat-datatype = ls_attr-type_name.
        APPEND ls_fcat TO Et_fcat.

      ENDLOOP.

      cl_alv_table_create=>create_dynamic_table(
        EXPORTING
          it_fieldcatalog           = Et_fcat
          i_length_in_byte          = abap_true
        IMPORTING
          ep_table                  = lo_table
        EXCEPTIONS
          generate_subpool_dir_full = 1
          OTHERS                    = 2
      ).

      IF sy-subrc <> 0.
*       MESSAGE ID sy-msgid TYPE sy-msgty NUMBER sy-msgno
*                  WITH sy-msgv1 sy-msgv2 sy-msgv3 sy-msgv4.
      ENDIF.

      " if node is multiple ( 0..n / 1..n ) return table type
      IF io_node_info->is_multiple( ) EQ abap_true.
        eo_data = lo_table.
      ELSE.
        FIELD-SYMBOLS: <lt_table> TYPE STANDARD TABLE.
        ASSIGN lo_table->* TO <lt_table>.
        IF <lt_table> IS ASSIGNED.

          CREATE DATA eo_data LIKE LINE OF <lt_table>.

        ENDIF.
        " else, return the
      ENDIF.
    CATCH cx_root INTO lx_root.
      ed_error_message = lx_root->get_text( ).
  ENDTRY.
ENDMETHOD.

----------------------------------------------------------

GET_DATA( )

Parameters:

Logic:

METHOD GET_DATA .

  DATA lv_count         TYPE i.
  DATA ls_fcat          TYPE lvc_s_fcat.
  DATA lv_index         TYPE i.
  DATA lv_attr_name     TYPE string.
  DATA lx_root          TYPE REF TO cx_root.

  FIELD-SYMBOLS: <lt_data> TYPE STANDARD TABLE,
                 <ls_data> TYPE any,
                 <lv_value> TYPE any.

  TRY.

      IF io_node IS NOT BOUND.
        ed_error_message = 'Node reference cannot be empty'.
        RETURN.
      ENDIF.

      " Get node data type and attribute list

     wd_this->get_node_data_type(
        EXPORTING
          io_node_info = io_node->get_node_info( )
        IMPORTING
          eo_data = eo_data
          et_fcat = et_fcat
          ed_error_message = ed_error_message
      ).

      " Return if any error or data type is not bound
      IF ed_error_message IS NOT INITIAL OR
         eo_data IS NOT BOUND.

        RETURN.
      ENDIF.

      ASSIGN eo_data->* TO <lt_data>.

      " get the no. of elements available in context node
      lv_count = io_node->get_element_count( ).

      " do for each element
      DO lv_count TIMES.

        " collect index value
        lv_index = sy-index.

        " Create a blank line and get the ref into <ls_dat>
        APPEND INITIAL LINE TO <lt_data> ASSIGNING <ls_data>.
        " return if line type is not assigned
        IF <ls_data> IS NOT ASSIGNED.
          RETURN.
        ENDIF.

        " Loop over each field/attribute and get the data
        LOOP AT et_fcat INTO ls_fcat.

          ASSIGN COMPONENT ls_fcat-fieldname
          OF STRUCTURE <ls_data> TO <lv_value>.

          IF <lv_value> IS ASSIGNED.
            lv_attr_name = ls_fcat-fieldname.

            io_node->get_attribute(
              EXPORTING
                index = lv_index
                name  = lv_attr_name
              IMPORTING
                value = <lv_value>
            ).
          ENDIF.

        ENDLOOP.

      ENDDO.

    CATCH cx_root INTO lx_root.
      ed_error_message = lx_root->get_text( ).
  ENDTRY.
ENDMETHOD.

----------------------------------------------------

Example:

Scenario: Let us say we need to read data from a node "NODE_DYN".

--------------------------

" Data declarations

DATA: lo_data TYPE REF TO data.
DATA lo_node TYPE REF TO if_wd_context_node.

FIELD-SYMBOLS: <lt_data> TYPE STANDARD TABLE.

     " Get node information

      wd_this->get_node_info(
        EXPORTING
          id_node_name     = 'NODE_DYN'
*      io_parent_node   =
        IMPORTING
*      eo_node_info     = LO_NODE_INFO
          eo_node          = lo_node
*      ed_error_message =
      ).

     " Get the data from context node

     wd_this->get_data(
        EXPORTING
          io_node          = lo_node
        IMPORTING
          eo_data          = lo_data
*     et_fcat          =
*     ed_error_message =
      ).

     " assign data into dynamic table

      ASSIGN lo_data->* to <lt_data>.

--------------------------

The internal table <lt_data> contains the data of our node "NODE_DYN"