为了避免因Activity生命周期而导致持久化蓝牙连接混乱问题，可以将蓝牙连接的逻辑放在Application类或者Service中。这样可以避免在Activity的生命周期中频繁打开或关闭蓝牙连接，从而保证蓝牙连接的稳定性。

示例代码：

public class MyApplication extends Application {

private static final String TAG = "MyApplication";
private BluetoothAdapter mBluetoothAdapter;
private BluetoothSocket mBluetoothSocket;

@Override
public void onCreate() {
    super.onCreate();
    mBluetoothAdapter = BluetoothAdapter.getDefaultAdapter();
    if (mBluetoothAdapter == null) {
        Log.e(TAG, "Unable to obtain BluetoothAdapter.");
        return;
    }
    BluetoothDevice device = mBluetoothAdapter.getRemoteDevice(MAC_ADDRESS);
    try {
        mBluetoothSocket = device.createRfcommSocketToServiceRecord(MY_UUID);
        mBluetoothSocket.connect();
    } catch (IOException e) {
        Log.e(TAG, "Unable to connect to Bluetooth socket.", e);
        try {
            mBluetoothSocket.close();
        } catch (IOException closeException) {
            Log.e(TAG, "Unable to close Bluetooth socket.", closeException);
        }
    }
}

@Override
public void onTerminate() {
    super.onTerminate();
    if (mBluetoothSocket != null) {
        try {
            mBluetoothSocket.close();
        } catch (IOException e) {
            Log.e(TAG, "Unable to close Bluetooth socket.", e);
        }
    }
}

public BluetoothSocket getBluetoothSocket() {
    return mBluetoothSocket;
}

}

在Activity中获取BluetoothSocket对象：

BluetoothSocket mBluetoothSocket = ((MyApplication) getApplication()).getBluetoothSocket();