Custom BusinessDataListWebPart Pagination (Next Button) - pageindex never changes - sharepoint

Question

Pagination (Next button) doesn't work for custom BusinessDataListWebPart.
I am adding BusinessDataListWebPart using code. Everything works fine. I can see 20 data raw at the same time but when I click "Next Button", I can not see next 20-40 data. A postback occurs, but the pageindex never changes.
I am using following code to add BusinessDataListWebPart to the Sharepoint site.
BusinessDataListWebPart consumer = new BusinessDataListWebPart();
consumer.Title = title;
consumer.Application = instance.Name;
consumer.Entity = projEntity.Name;
consumer.XslLink = "/Style%20Library/XSL%20Style%20Sheets/" + xslFileName;
consumer.PageSize = 20;

Answer 1

OK..I found the answer.
For pagination I needed to add "ParameterBindings" to the business data list webpart.
My final code is, It works perfect.
BusinessDataListWebPart consumer = new BusinessDataListWebPart();
ServerContext serverContext = ServerContext.GetContext(site);
SqlSessionProvider.Instance().SetSharedResourceProviderToUse(serverContext);
LobSystemInstance instance = ApplicationRegistry.GetLobSystemInstanceByName(applicationName);
Entity projEntity = instance.GetEntities()[entityName];
consumer.Title = title;
consumer.Application = instance.Name;
consumer.Entity = projEntity.Name;
consumer.XslLink = "/Style%20Library/XSL%20Style%20Sheets/" + xslFileName;
consumer.PageSize = 20;
consumer.ParameterBindings = "<ParameterBinding Name=" + "\"dvt_firstrow\"" + " Location=" + "\"Postback;Connection\"" + "/>" +
" <ParameterBinding Name=" + "\"dvt_sortdir\"" + " Location=" + "\"Postback;Connection\"" + "/>" +
" <ParameterBinding Name=" + "\"dvt_sortfield\"" + " Location=" + "\"Postback;Connection\"" + "/>" +
" <ParameterBinding Name=" + "\"dvt_filterfields\"" + " Location=" + "\"Postback;Connection\"" + "/>" +
" <ParameterBinding Name=" + "\"dvt_partguid\"" + " Location=" + "\"Postback;Connection\"" + "/>";