IOException: read failed, socket might closed - Bluetooth on Android 4.3

Question

Currently I am trying to deal with a strange Exception when opening a BluetoothSocket on my Nexus 7 (2012), with Android 4.3 (Build JWR66Y, I guess the second 4.3 update). I

Answer 1

I had the same symptoms as described here. I could connect once to a bluetooth printer but subsequent connects failed with "socket closed" no matter what I did.

I found it a bit strange that the workarounds described here would be necessary. After going through my code I found that I had forgot to close the socket's InputStream and OutputSteram and not terminated the ConnectedThreads properly.

The ConnectedThread I use is the same as in the example here:

http://developer.android.com/guide/topics/connectivity/bluetooth.html

Note that ConnectThread and ConnectedThread are two different classes.

Whatever class that starts the ConnectedThread must call interrupt() and cancel() on the thread. I added mmInStream.close() and mmOutStream.close() in the ConnectedTread.cancel() method.

After closing the threads/streams/sockets properly I could create new sockets without any problem.