File transfer over Wi-Fi in Android

问题:

I want to make an Android app which can transfer a file from one phone to another via Wi-Fi. In Android 4.0 it can be done through Wi-Fi direct but how it would be possible for lower versions that do not support Wi-Fi direct?

回答1:

You can do this by opening a network connection. This will work over Wifi or any connection the device has. Let's say device A wants to send to device B a file.

1. B opens a listening port
2. A opens the file as an input stream
3. A connects to B's listening port
4. A sends the file through the socket
5. A closes the socket
6. B writes its buffer in a new file

Check this reference and ask if you have any problems.