What is singleton property in Webdynpro

Question

Hi,
What is singleton property in Webdynpro?
please explian along with diagram
Regards,
Sid.

Answer 1

hi,
Singleton Nodes
•     It is very important to remember the difference in runtime behaviour between a singleton node and a non-singleton node. When a node is declared to be singleton, there will only ever be only one instance of that node-irrespective of the number of elements found in the parent node’s element collection. This is not the case for the non-singleton node. In this case, there will be as many instances of the non-singleton child nodes as there are elements in the parent node’s element collection.
•     The significant point here is that when the lead selection in the parent element collection changes, the contents of the singleton child node become invalid. Consequently, the next time data is required from the singleton child node, the entire element collection must be rebuild in order that it match the data in the newly selected parent element.
•     The task of rebuilding singleton child node must be performed by a dedicated supply function.
[http://help.sap.com/saphelp_nw70/helpdata/EN/81/95384162316532e10000000a1550b0/frameset.htm]
regards,
pinki