QBluetooth connect mouse, keyboard or speaker

Mihan

Hi
I want to use QtBluetooth to connect some bluetooth devices like mouse or keyboard.
But After using QBluetoothDeviceDiscoveryAgent to scan the device, I have no idea what should I do next:

use QBluetoothSocket to connect the device with the information I got by the scanner.
or use QBluetoothServer to listen.

which one is right? Or are both wrong?

Also after connecting the device, how can I use the data from the devices, e.g. when the mouse move, how can I know the distance and direction it moved and how to control the cursor.

Regards
Mihan