How to get battery level of left and right earbuds in android

Question

I want to create a app that display's Battery levels of left and right earbuds in android using Java I have tried that code

BluetoothDevice device = bluetoothAdapter.getRemoteDevice(deviceAddress);
Method m = device.getClass().getMethod("getBatteryLevel");
int batteryLevel = m.invoke(device);

But in this Mathod i can get always only a single Battery Level not Both and i don't know how to get both battery levels, so i need your help to get battery level of left and right earbuds in android.

Answer 1

To find out the battery level of the left and right earbuds in Android using Java, you need to use the Bluetooth Low Energy (BLE) protocol, since most modern wireless earbuds communicate their battery information over BLE. Here is a general overview of the steps you need to follow: Ensure that you have the necessary permissions in your AndroidManifest.xml

<uses-permission android:name="android.permission.BLUETOOTH"/>
<uses-permission android:name="android.permission.BLUETOOTH_ADMIN"/>
<uses-permission android:name="android.permission.BLUETOOTH_CONNECT"/>
<uses-permission android:name="android.permission.BLUETOOTH_SCAN"/>
<uses-permission android:name="android.permission.BATTERY_STATS"/>

then you need to get reference to the BluetoothAdapter and discovery a bluetooth device .

BluetoothAdapter bluetoothAdapter = BluetoothAdapter.getDefaultAdapter();

Set<BluetoothDevice> pairedDevices = bluetoothAdapter.getBondedDevices();

for (BluetoothDevice device : pairedDevices) {
    // Check if the device name or address matches your earbuds
    if (device.getName().equals("YourBlutoothDeviceName") || device.getAddress().equals("LeftEarbudMACAddress")) {
        // You found the left earbud, proceed to get its battery level.
        // Repeat this for the right earbud if needed.
    }
}

then to determine the battery level, you need to connect the headset and then query the Bluetooth GATT battery service.

BluetoothGatt gatt = device.connectGatt(context, false, gattCallback);

// Define a BluetoothGattCallback to handle GATT events
BluetoothGattCallback gattCallback = new BluetoothGattCallback() {
    @Override
    public void onConnectionStateChange(BluetoothGatt gatt, int status, int newState) {
        if (newState == BluetoothProfile.STATE_CONNECTED) {
            // Once connected, discover services
            gatt.discoverServices();
        }
    }

    @Override
    public void onServicesDiscovered(BluetoothGatt gatt, int status) {
        if (status == BluetoothGatt.GATT_SUCCESS) {
            // Find the Battery Service
            BluetoothGattService batteryService = gatt.getService(UUID.fromString("0000180f-0000-1000-8000-00805f9b34fb"));

            if (batteryService != null) {
                // Find the Battery Level Characteristic
                BluetoothGattCharacteristic batteryLevelCharacteristic = batteryService.getCharacteristic(UUID.fromString("00002a19-0000-1000-8000-00805f9b34fb"));

                if (batteryLevelCharacteristic != null) {
                    // Read the battery level
                    gatt.readCharacteristic(batteryLevelCharacteristic);
                }
            }
        }
    }

    @Override
    public void onCharacteristicRead(BluetoothGatt gatt, BluetoothGattCharacteristic characteristic, int status) {
        if (status == BluetoothGatt.GATT_SUCCESS) {
            // Extract the battery level value from the characteristic
            int batteryLevel = characteristic.getIntValue(BluetoothGattCharacteristic.FORMAT_UINT8, 0);
            // Handle the battery level value (e.g., display it in your UI)
        }
        // Disconnect the GATT connection when you're done
        gatt.disconnect();
    }
};

References https://developer.android.com/guide/topics/connectivity/bluetooth/ble-overview

Android and Bluetooth Low Energy (BLE)