Bluetooth pairing fails when using two android devices

[Alexander Glogger]

When using btPairDevice(), the PairingBroadcastReceiver (automatic pairing confirmation) is only registered for the device from which the paring request is started. However, since the corresponding confirmation, for successful pairing must be confirmed on both devices, the PairingBroadcastReceiver must also be registered for the second device.

mobly-bundled-snippets/src/main/java/com/google/android/mobly/snippet/bundled/bluetooth/BluetoothAdapterSnippet.java

Lines 261 to 280 in b058548

 @Rpc(description = "Pair with a bluetooth device.") 
 public void btPairDevice(String deviceAddress) throws Throwable { 
     BluetoothDevice device = mDiscoveryResults.get(deviceAddress); 
     if (device == null) { 
         throw new NoSuchElementException( 
                 "No device with address " 
                         + deviceAddress 
                         + " has been discovered. Cannot proceed."); 
     } 
     mContext.registerReceiver( 
             new PairingBroadcastReceiver(mContext), PairingBroadcastReceiver.filter); 
     if (!(boolean) Utils.invokeByReflection(device, "createBond")) { 
         throw new BluetoothAdapterSnippetException( 
                 "Failed to initiate the pairing process to device: " + deviceAddress); 
     } 
     if (!Utils.waitUntil(() -> device.getBondState() == BluetoothDevice.BOND_BONDED, 120)) { 
         throw new BluetoothAdapterSnippetException( 
                 "Failed to pair with device " + deviceAddress + " after 2min."); 
     } 
 } 

My solution for this problem was implementing a additional Rpc-function which is only used to register the broadcast receiver for any device as required.

public void btStartPairingBroadcastReceiver () {
    mContext.registerReceiver(new PairingBroadcastReceiver(mContext), PairingBroadcastReceiver.filter);
}