Extend Purchase Contract Approval Apps

Hi,

We are trying to extend the Purchase Contract Approval by adding custom field in item detail view using extended Odata. We are able to view the header detail view but when try to access item detail view error below occur in IE. Thanks

Uncaught Error: The segment {SAP__Origin} is required.

When we commend out the code not to use extended odata. It's working fine with standard odata but of course without the new added field data.