FenceRegisterUnregister.java

@Override
protected void onStart() {
    super.onStart();
    setupFence();
    registerReceiver(mFenceReceiver, new IntentFilter(FenceReceiver.FENCE_RECEIVER_ACTION));
}

@Override
protected void onStop() {
    super.onStop();
    unregisterFence();
    unregisterReceiver(mFenceReceiver);
}