How to update table view custom fields using 'Do_Prepare_Output'

Hi All,

  How to update table view custom fields in 'Do_prepare_output' method? I have added three custom fields in related BOL structure using 'Append Structure'. When i am trying to update those custom fields using 'Set_Property' method in 'do_prepare_output' values are not saving and iterator ->get_next( ) method is not working (looping only one item). Sample code below.

Code:

lr_col ?= me->typed_context->btordprd->collect_wrapper.

lr_iterator ?= lr_col->get_iterator( ).

if lr_iterator( ) is bound.

lr_entity ?= lr_iterator->get_first( ).

while lr_entity is bound.

if lr_entity->lock( ) = abap_true.

set_property( lv_cust1)

.

.

endif.

lr_entity ?= lr_iterator->get_next( ).

endwhile.

endif.

Please give me suggestions to update custom fields in table view.

Thanks & Regards,

Nirish