Android仿QQ微信实时监测网络状态

先简单说一下思路：网络变化时系统会发出广播。所以我们监听这个广播，利用接口回调通知activity做相应的操作就好了。

思路

• 判断网络状态（写个工具类NetUtil）

• 写个类继承BroadcastReceiver（不要忘记在清单文件中注册）

• 需要在清单文件中添加权限

<uses-permission android:name="android.permission.ACCESS_NETWORK_STATE">
</uses-permission>

• 回调接口（NetEvevt）

• BaseActivity实现这个接口

直接上代码

NetUtil

import android.content.Context;
import android.net.ConnectivityManager;
import android.net.NetworkInfo;

/**
* Author: lenovo
* Date: 2018/2/26
* email: 1271396448@qq.com
*/

public class NetUtil {

/**
 * 没有连接网络
 */
public static final int NETWORK_NONE = -1;
/**
 * 移动网络
 */
public static final int NETWORK_MOBILE = 0;
/**
 * 无线网络
 */
public static final int NETWORK_WIFI = 1;

public static int getNetWorkState(Context context) {

// 得到连接管理器对象
 ConnectivityManager connectivityManager = (ConnectivityManager) context
   .getSystemService(Context.CONNECTIVITY_SERVICE);

NetworkInfo activeNetworkInfo = connectivityManager
   .getActiveNetworkInfo();
 if (activeNetworkInfo != null && activeNetworkInfo.isConnected()) {
  if (activeNetworkInfo.getType() == (ConnectivityManager.TYPE_WIFI)) {
   return NETWORK_WIFI;
  } else if (activeNetworkInfo.getType() == (ConnectivityManager.TYPE_MOBILE)) {
   return NETWORK_MOBILE;
  }
 } else {
  return NETWORK_NONE;
 }
 return NETWORK_NONE;
}

}

NetBroadReceiver

import android.content.BroadcastReceiver;
import android.content.Context;
import android.content.Intent;
import android.net.ConnectivityManager;

/**
* Author: lenovo
* Date: 2018/2/26
* email: 1271396448@qq.com
*/

public class NetBroadcastReceiver extends BroadcastReceiver {
public NetEvevt evevt = BaseActivity.evevt;

@Override
public void onReceive(Context context, Intent intent) {
 // TODO Auto-generated method stub
 // 如果相等的话就说明网络状态发生了变化
 if (intent.getAction().equals(ConnectivityManager.CONNECTIVITY_ACTION)) {
  int netWorkState = NetUtil.getNetWorkState(context);
  // 接口回调传过去状态的类型
  evevt.onNetChange(netWorkState);
 }
}

// 自定义接口
public interface NetEvevt {
 public void onNetChange(int netMobile);
}
}

BaseActivity

import android.os.Bundle;
import android.support.v4.app.FragmentActivity;

/**
* Author: lenovo
* Date: 2018/2/26
* email: 1271396448@qq.com
*/

abstract public class BaseActivity extends FragmentActivity implements NetBroadcastReceiver.NetEvevt {

public static NetBroadcastReceiver.NetEvevt evevt;
/**
 * 网络类型
 */
private int netMobile;

@Override
protected void onCreate(Bundle arg0) {
 // TODO Auto-generated method stub
 super.onCreate(arg0);
 evevt = this;
 inspectNet();
}

/**
 * 初始化时判断有没有网络
 */

public boolean inspectNet() {
 this.netMobile = NetUtil.getNetWorkState(BaseActivity.this);
 return isNetConnect();

// if (netMobile == 1) {
 // System.out.println("inspectNet：连接wifi");
 // } else if (netMobile == 0) {
 // System.out.println("inspectNet:连接移动数据");
 // } else if (netMobile == -1) {
 // System.out.println("inspectNet:当前没有网络");
 //
 // }
}

/**
 * 网络变化之后的类型
 */
@Override
public void onNetChange(int netMobile) {
 // TODO Auto-generated method stub
 this.netMobile = netMobile;
 isNetConnect();

}

/**
 * 判断有无网络 。
 *
 * @return true 有网, false 没有网络.
 */
public boolean isNetConnect() {
 if (netMobile == 1) {
  return true;
 } else if (netMobile == 0) {
  return true;
 } else if (netMobile == -1) {
  return false;

}
 return false;
}

}

MainActivity

import android.os.Bundle;
import android.view.View;
import android.widget.ListView;
import android.widget.TextView;

public class MainActivity extends BaseActivity {

private TextView textView,txtView;
ListView listView; //声明一个ListView对象

@Override
protected void onCreate(Bundle savedInstanceState) {
 super.onCreate(savedInstanceState);
 setContentView(R.layout.activity_main);
 textView= (TextView) findViewById(R.id.textView);
 txtView=(TextView)this.findViewById(R.id.txtView);

//启动时判断网络状态
 boolean netConnect = this.isNetConnect();
 if (netConnect){
  textView.setVisibility(View.GONE);
  txtView.setText("网络连接正常");
 }else {
  textView.setVisibility(View.VISIBLE);
  txtView.setText("网络连接异常");
 }
}

@Override
public void onNetChange(int netMobile) {
 super.onNetChange(netMobile);
 //网络状态变化时的操作
 if (netMobile==NetUtil.NETWORK_NONE){
  textView.setVisibility(View.VISIBLE);
  txtView.setText("网络连接异常");
 }else {
  textView.setVisibility(View.GONE);
  txtView.setText("网络连接正常");
 }
}

}

记得在清单文件中注册

<receiver android:name="cn.broadcastreceiver.NetBroadcastReceiver" >
<intent-filter>
 <action android:name="android.net.conn.CONNECTIVITY_CHANGE" />
</intent-filter>
</receiver>

来源：https://blog.csdn.net/qq1271396448/article/details/79373163