场景：选择非默认的网卡走流量

安卓接口示例：

connectivityManager.requestNetwork(build, new ConnectivityManager.NetworkCallback() {
            @Override
            public void onAvailable(Network network) {
                super.onAvailable(network);
                try {
                    if (Build.VERSION.SDK_INT >= 23) {
                        connectivityManager.bindProcessToNetwork(network); 
                    } else {
                        ConnectivityManager.setProcessDefaultNetwork(network);
                    }
                    // 之后创建socket
                   // ...
                 } catch (Exception e) {
                    e.printStackTrace();
                }
            }