Error in buttun action

Hi All,

I have action on button to save to database my code like this:

method ONACTIONSAVE2 .

DATA ls_trans_details TYPE REF TO wd_this->ELEMENTS_TRANSTYPE_INSERT.

ls_trans_details ?= wd_context->get_child_node( name = wd_this->wdctx_transtype_insert

)->get_element( )->get_static_attributes_ref( ).

CALL METHOD wd_comp_controller->model->SAVE_TANS_DETAILS( ls_trans_details->* ).

endmethod.

but in have hot this error:

< none> is not type-compatible with formal parameter

kindly if there is any help on this.

Regards

ghadeer