how to realize clear function on Zview like standard search view

Hi experts,

    My requirement is to realize a clear function like the standard search page on my own Zview to clear the search criteria inputted by user.

    The problem is that even i clear the data in the context node, the data is still shown on UI, like a browser buffer problem..

    But the standard view works well.

    So if you have any idea on this, please kindly help me.

    Thanks in advance.

    Blow is my code in clear method..

METHOD eh_onclear.

      DATA:

   lr_col_wrap      TYPE REF TO if_bol_bo_col,

   lr_current       TYPE REF TO cl_crm_bol_query_service,

   lr_value_node    TYPE REF TO cl_bsp_wd_value_node,

   lr_struct_ref    TYPE zclm_search_ui.

   FIELD-SYMBOLS:

     <struct_ref>     TYPE        any.

* create new value entity; clear collection; add entity to collection

   lr_col_wrap ?= me->typed_context->CUSCLMQUERY->get_collection_wrapper( ).

   lr_current ?= lr_col_wrap->get_current( ).

   lr_current->get_properties( IMPORTING es_attributes = lr_struct_ref ).

   CLEAR lr_struct_ref.

   lr_current->set_properties( EXPORTING is_attributes = lr_struct_ref ).

* reset invalid input in context node

   me->typed_context->CUSCLMQUERY->if_bsp_model~reset_errors( ).

   ENDMETHOD.