transfer files between android devices using WIFI direct

I'm trying to trying to build an application that can transfer files between android devices using WIFI direct. I does have to be p2p connection, I just want to send pictures. I tried 1) http://ift.tt/1qa8huU it didn't work I also tried 2) http://ift.tt/1EpXcgc

It give me an error at this String localIP = Utils.getLocalIPAddress(); code.

3) how to transfer files between android devices using WIFI direct , didn't work Any help appropriated.