Does Android 4.3 support multiple BLE device conne

问题:

I am currently working on Android 4.3 Bluetooth Low Energy, I am able to connect to a device, get services, read/write service. Now when I try to connect to second device, services of second device is received and first device services are lost. Now when I try to connect to write/read characteristic of first device, nothing works.

Has any one tried connecting to multiple devices. How do you initialize Gatt for two devices?

回答1:

I think SAMSUNG BLE API and Google's API have Broadcom Ble stack and Broadcom stack not supported multiple ble device currently.

回答2:

I had exactly the same behavior on the Samsung BLE stack (galaxy S4). I hacked the samsung code and fixed it:

The class BluetoothGatt keeps a list of "all" discovered services. A call to BluetoothGatt->discoverServices will clear this list. I drived my own class and modified the behaviour of the function to only delete the services of the concerning BluetoothDevice. This is my code:

public class MyBluetoothGatt extends BluetoothGatt {

    MyBluetoothGatt(Context paramContext, BluetoothProfile.ServiceListener paramServiceListener)
      {
        super(paramContext, paramServiceListener);
      }

    public final boolean discoverServices(BluetoothDevice paramBluetoothDevice)
      {
        if (paramBluetoothDevice == null)
        {
          Log.e("BtGatt.BluetoothGatt", "discoverServices() - device is null ");
          return false;
        }
        Log.d("BtGatt.BluetoothGatt", "discoverServices() - device: " + paramBluetoothDevice.getAddress());

        if ((d == null) || (this.f == 0))
          return false;
// old code     this.h.clear();

//--new code
        @SuppressWarnings("rawtypes")
        Iterator localIterator = this.h.iterator();
        while (localIterator.hasNext())
        {
          BluetoothGattService localBluetoothGattService;
          localBluetoothGattService = (BluetoothGattService)localIterator.next();

          if (localBluetoothGattService.a().equals(paramBluetoothDevice))
          {
              this.h.remove(paramBluetoothDevice);
          }
        }       
//end new code      


        this.d.discoverServices(this.f, paramBluetoothDevice.getAddress());


        return true;
      }

}

i also had to use a class editor to remove some of the "final" modifiers in order to be able to dervive my own class. It was a big hack but now it's working beautifully. I will upgrade my S4 to android 4.3 once the official release comes out and port my code, so fingers crossed this will work for android 4.3 as well.

回答3:

It should work for all if you implement different BluetoothGatt instance and different GattCallback for each device you want to connect...