BSP OnInputProcessing Table Page Attribute

Hi,

I am trying to pass the 'SD_DOCUMENT_FLOW_GET' function's table result to the html layout.

But when I try to activate my OnInputProcessing code it gets error : ' The result type of the function method cannot be converted into the type of LT_DOCFLOW. '

LT_DOCFLOW and ET_DOCFLOW are same type why am I getting this error? Any help would be appreciated.

In Page Attributes;

In OnInputProcessing Event Handler;

* event handler for checking and processing user input and

* for defining navigation

DATA : IV_DOCNUM  TYPE VBELN,

        Lt_docflow TYPE REF TO TDS_DOCFLOW.

navigation->set_parameter( name  = 'bnumber' ).

iv_docnum = navigation->get_parameter( name = 'bnumber' ).

case event_id.

   when 'Detail'.

     CALL FUNCTION 'CONVERSION_EXIT_ALPHA_INPUT'

       EXPORTING

         INPUT  = iv_docnum

       IMPORTING

         OUTPUT = iv_docnum.

     CALL FUNCTION 'SD_DOCUMENT_FLOW_GET'

       EXPORTING

         IV_DOCNUM  = iv_docnum

       IMPORTING

         ET_DOCFLOW = et_docflow.

navigation->set_parameter( name  = 'et_docflow').

lt_docflow = navigation->get_parameter( name = 'et_docflow' ).

ENDCASE.