Once you have discovered a desired BluetoothDevice object, you can connect to it by using its connectGatt()
method which takes as parameters a Context object, a boolean indicating whether to automatically connect to the BLE device and a BluetoothGattCallback reference where connection events and client operations results will be delivered:
if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.M) {
device.connectGatt(context, false, bluetoothGattCallback, BluetoothDevice.TRANSPORT_AUTO);
} else {
device.connectGatt(context, false, bluetoothGattCallback);
}
Override onConnectionStateChange
in BluetoothGattCallback to receive connection an disconnection events:
BluetoothGattCallback bluetoothGattCallback =
new BluetoothGattCallback() {
@Override
public void onConnectionStateChange(BluetoothGatt gatt, int status,
int newState) {
if (newState == BluetoothProfile.STATE_CONNECTED) {
Log.i(TAG, "Connected to GATT server.");
} else if (newState == BluetoothProfile.STATE_DISCONNECTED) {
Log.i(TAG, "Disconnected from GATT server.");
}
}
};