android通过蓝牙发送文件而不配对

Question

There's a way I can send a file to an android device (wich already has my app installed) without paring or the app making the pairing in the background? (Without user intervention)

In my country just few people have data plans in their phones, so I want to create some kind of "server" using a raspberry and a bluetooth dongle so everytime an user with my app it's inside my store, I can show them notifications (with images and text) using the bluetooth connection insted of their cellphone data. (To detect they are in my store I can use geofences or regular beacons)

Answer 1

BLE is not intended to send files with huge size, since it can maximally send 20 byte chunks of data at a time. I'll definately go for the standard Bluetooth protocol if you have a file consisting of a huge size.

The pairing notification depends on how the app has been developed. If you know the device address (MAC address as unique ID) of the remote device beforehand, then you can make a simple "if" statement that checks whether the device address of each discovered device equals the one you have defined. If yes, then you can establish a connection. As a result, the app will automatically establish a connection with the desired device.