Displaying value description is standard functionality.
To display value i.e. key on screen you
Step1. Define static,public attributes in the impl class of view.
a. GV_KEY - char40
b. GV_FIELDNAME - String
Step2. Write below code in the redefined method DO_HANDLE_DATA. of impl class of view.
CALL METHOD super->do_handle_data
EXPORTING
form_fields = form_fields
global_messages = global_messages.
DATA: ls_fields TYPE ihttpnvp.
READ TABLE form_fields INTO ls_fields WITH KEY name = 'zaddress_rec_city'.
gv_key = ls_fields-value.
CONCATENATE me->component_id '_zaddress_rec_city' INTO gv_fieldname.
In the above code zaddress is my contextnode name and rec_city is my field name.
Step3. Write the following code on htm page.
<script>
var fieldname = "<%= controller->gv_fieldname %>";
var list = document.getElementById(fieldname);
list.value = "<%= controller->gv_key %>";
</script>