I already knew the basic of android programming, especially the one at game. now I want to try multiplayer game. but I dont have any background about multiplayer game. so I want have a number of question :
I don't plan to make any sophisticated game yet. may be just multiplayer tic tac toe is alright for me. the most important is that I understand the basic of multiplayer game programming. :)
I would give this series of articles a read:
http://gafferongames.com/networking-for-game-programmers/
It's mostly in C/C++, but you can translate it to Java. Learn about UDP sockets in Java, for example:
http://download.oracle.com/javase/tutorial/networking/datagrams/index.html
This should be enough to get you going. I would probably do client-server setup. You can do P2P but it's harder from what I've heard.