Proxy.PROXY_CHANGE_ACTION

Question

我在代码中的回调为什么不好使？
    public synchronized void enablePlatformNotifications() {
        if (mProxyChangeReceiver == null) {
            mProxyChangeReceiver =
                    new BroadcastReceiver() {
                        @Override
                        public void onReceive(Context ctx, Intent intent) {
                            setProxyConfig();
                        }
                    };
            mContext.registerReceiver(mProxyChangeReceiver,
                                      new IntentFilter(Proxy.PROXY_CHANGE_ACTION));
        }
    }正常是调用了enablePlatformNotifications（）应该会走onReceive(),为什么一直就没有调用过呢？