Call a external vendor catalog - OCI In ECC using web dynpro

Question

Hello Everyone,
We have a requirement to call a OCI External Catalog in ME51n Transaction in ECC, that is working fine.
Now we need to create a Web dynpro ABAP Application which performs the Task of ME51n Transaction along with OCI Integration.
So far i have create a small Web dynpro ABAP application to check does OCI Catalog can be integrated in ECC using web dynpro ABAP.
My Screen Consit of a single Button UI, on click of the button i am calling the External Catalog, from the catalog i select all the materials and click on submit finally we need to bring all the selected materials to get displayed ina table.
Half of the Development is done i.e i am able to call the catalog but not able to receive the selected materials.
following are the details-
1. I check in SRM first how the Ctalogs are been called, i found 2 Services responsible for the same in SICF transaction -
Inbound HLDR and Outbound HLDR which uses handler class as SAPSRM_CL_CH_WD_INBOUND_HDLR and SAPSRM_CL_CH_WD_OUTBOUND_HDL, so i copied the same classes into ECC and created the same SICF Service.
Contn. in next post

Answer 1

2.In my Web Dynpro ABAP application i have a Inbound plug in my window in the  handler method of the inbound plug i fill a table lt_parameters of  TYPE tihttpnvp, it has 2 columns name and value
In this table i fill following entries-
Name-CATALOG_URL
Value-https://XXXXXXXX.com/invoke/BVProcess.SAPOCI/processCatalogRequest
Name-USERNAME
Value-XXXXXXXX
Name-PASSWORD
Value-XXXXXXXX
NAME  = 'HOOK_URL'.
VALUE = 'http:/XXXXX.hostederp.local:8000/sap/ZOTC_CAT/Zinbound_hdlr'."?TARGET_URL= {Appdress of the WDA Apllication}
NAME  = 'OCI_VERSION'.
VALUE = '4.0'.
NAME  = 'OPI_VERSION'.
VALUE = '1.0'.
NAME  = 'returntarget'.
VALUE = _top
also in this inbound plug handler method i fill a lv_url variable of type string with-
lv_url = 'http://XXXXXX.hostederp.local:8000/sap/ZOTC_CAT/Zoutbound_hdlr?sap-client=100&sap-language=E'.
3. finally from the handler method of the inbound plug i call a Suspend plug p[assing the above two variables i.e
lt_parameters and  lv_url.
wd_this->fire_zw_suspend_plg( url =    lv_url   i_parameter_tab = lt_parameters ).
4. Using above i cam able to call the catalog and select the materials.
5. Now if i Finally clcik on submit on the catalog it should return the materials to the WDA Application.
For WDA Application to accept the Materials i have created a resume plug in which i am using -
wdr_task=>server->request->get_form_fields( CHANGING fields = lt_fields ). to get all the selected materials into lt_fields.
6. But unfortunately i am unable to receive the selected materials in lt_fields.
I think i am missing something in Hook URL or some other parameter.
Please help, ur comments and suggestions are welcome.
Regards,
Akash Rana