思路步骤：

1、Android提供有获取当前总流量的方法

2、上一秒 减去 下一面的流量差便是网速

3、注意计算

1>计算网速的工具类：

package imcs.cb.com.viewapplication.utils;

import android.content.Context;

import android.net.TrafficStats;

import android.os.Handler;

import android.os.Message;

import java.util.Timer;

import java.util.TimerTask;

/**

* Created by Ricky on 2016/10/13.

*/

public class NetWorkSpeedUtils {

private Context context;

private Handler mHandler;

private long lastTotalRxBytes = 0;

private long lastTimeStamp = 0;

public NetWorkSpeedUtils(Context context, Handler mHandler){

this.context = context;

this.mHandler = mHandler;

}

TimerTask task = new TimerTask() {

@Override

public void run() {

showNetSpeed();

}

};

public void startShowNetSpeed(){

lastTotalRxBytes = getTotalRxBytes();

lastTimeStamp = System.currentTimeMillis();

new Timer().schedule(task, 1000, 1000); // 1s后启动任务，每2s执行一次

}

private long getTotalRxBytes() {

return TrafficStats.getUidRxBytes(context.getApplicationInfo().uid) == TrafficStats.UNSUPPORTED ? 0 :(TrafficStats.getTotalRxBytes()/1024);//转为KB

}

private void showNetSpeed() {

long nowTotalRxBytes = getTotalRxBytes();

long nowTimeStamp = System.currentTimeMillis();

long speed = ((nowTotalRxBytes - lastTotalRxBytes) * 1000 / (nowTimeStamp - lastTimeStamp));//毫秒转换

long speed2 = ((nowTotalRxBytes - lastTotalRxBytes) * 1000 % (nowTimeStamp - lastTimeStamp));//毫秒转换

lastTimeStamp = nowTimeStamp;

lastTotalRxBytes = nowTotalRxBytes;

Message msg = mHandler.obtainMessage();

msg.what = 100;

msg.obj = String.valueOf(speed) + "." + String.valueOf(speed2) + " kb/s";

mHandler.sendMessage(msg);//更新界面

}

}

2>使用：

private Handler mHnadler = new Handler(){

@Override

public void handleMessage(Message msg) {

switch (msg.what) {

case 100:

tv_speed.setText("当前网速： " + msg.obj.toString());

break;

}

super.handleMessage(msg);

}

};

@Override

protected void onCreate(Bundle savedInstanceState) {

super.onCreate(savedInstanceState);

setContentView(R.layout.activity_main);

tv_speed = (TextView) findViewById(R.id.tv_speed);

new NetWorkSpeedUtils(this,mHnadler).startShowNetSpeed();

}