Android实现监测网络状态

本文主要用到了安卓监测网络状态变化功能，实现了WIFI,3G,无网络状态切换时发出通知的功能。

主要知识点

service
broadcast
接口回调实现

service的基本知识

service可分为

按运行地点分类
- 本地服务
- 远程服务
按按运行类型分类：
- 前台服务
- 后台服务
按使用方式分类：
- startService 启动的服务
- bindService 启动的服务
- startService 同时也 bindService 启动的服务

service生命周期

这里写图片描述

详情请见参考链接：

Android 中的 Service 全面总结 - - 博客频道 - CSDN.NET

Android开发之如何保证Service不被杀掉（broadcast+system/app） - 其实并不难,是你太悲观 - 博客频道 - CSDN.NET

安卓监测网络状态变化

service部分

package com.zj.servicewifi;import java.util.Date;
import java.util.Timer;
import java.util.TimerTask;import android.app.Service;
import android.content.BroadcastReceiver;
import android.content.Context;
import android.content.Intent;
import android.content.IntentFilter;
import android.net.ConnectivityManager;
import android.net.NetworkInfo;
import android.os.Binder;
import android.os.IBinder;
import android.provider.SyncStateContract.Constants;
import android.util.Log;public class WIFIService extends Service{int IntentId;int NOINTENT=0;int WIFI=1;int GRS=2;// 实时监听网络状态改变  private BroadcastReceiver mReceiver = new BroadcastReceiver()  {  @Override  public void onReceive(Context context, Intent intent)  {  String action = intent.getAction();  if (action.equals(ConnectivityManager.CONNECTIVITY_ACTION))  {  Timer timer = new Timer();  timer.schedule(new QunXTask(getApplicationContext()), new Date());  }  }  };  public interface GetConnectState  {  public void GetState(int isConnected); // 网络状态改变之后，通过此接口的实例通知当前网络的状态，此接口在Activity中注入实例对象  }  private GetConnectState onGetConnectState;  public void setOnGetConnectState(GetConnectState onGetConnectState)  {  this.onGetConnectState = onGetConnectState;  }  private Binder binder = new MyBinder();  private boolean isContected = true;  @Override  public IBinder onBind(Intent intent)  {  return binder;  }  @Override  public void onCreate()  {// 注册广播  IntentFilter mFilter = new IntentFilter();  mFilter.addAction(ConnectivityManager.CONNECTIVITY_ACTION); // 添加接收网络连接状态改变的Action  registerReceiver(mReceiver, mFilter);  }  class QunXTask extends TimerTask  {  private Context context;  public QunXTask(Context context)  {  this.context = context;  }  @Override  public void run()  {  if (is3GConnected(context)&&isWifiConnected(context)==false)  {  System.out.println("hereere*************");IntentId= 2;} else if(isWifiConnected(context)){IntentId=WIFI;}else  {  IntentId=NOINTENT;}  if (onGetConnectState != null)  {  onGetConnectState.GetState(IntentId); // 通知网络状态改变  Log.i("mylog", "通知网络状态改变:" + IntentId);  }  }  /* * 判断是3G否有网络连接 */  private boolean is3GConnected(Context context)  {  if (context != null)  {  ConnectivityManager mConnectivityManager = (ConnectivityManager) context.getSystemService(Context.CONNECTIVITY_SERVICE);  NetworkInfo mNetworkInfo = mConnectivityManager.getActiveNetworkInfo();if (mNetworkInfo != null)  {  return mNetworkInfo.isAvailable();  }  }  return false;  }  /* * 判断是否有wifi连接 */  private boolean isWifiConnected(Context context)  {  if (context != null)  {  ConnectivityManager mConnectivityManager = (ConnectivityManager) context.getSystemService(Context.CONNECTIVITY_SERVICE);  NetworkInfo mWiFiNetworkInfo = mConnectivityManager.getNetworkInfo(ConnectivityManager.TYPE_WIFI);  if (mWiFiNetworkInfo != null)  {  return mWiFiNetworkInfo.isAvailable();  }  }  return false;  }  }  public class MyBinder extends Binder  {  public WIFIService getService()  {  return WIFIService.this;  }  }  @Override  public void onDestroy()  {  super.onDestroy();  unregisterReceiver(mReceiver); // 删除广播  }  }

注意，其中用到广播接收者，广播接收者有两种注册方式，在代码中注册与在XML文件中注册，本例中在代码中注册了，如果再在XML中注册，会报错

activity中代码

package com.zj.servicewifi;import com.zj.servicewifi.WIFIService.GetConnectState;import android.app.Activity;
import android.content.ComponentName;
import android.content.Intent;
import android.content.ServiceConnection;
import android.os.Bundle;
import android.os.Handler;
import android.os.IBinder;
import android.os.Message;
import android.util.Log;
import android.view.Menu;
import android.view.MenuItem;
import android.view.View;
import android.widget.Toast;public class MainActivity extends Activity {protected String TAG = "mylog";  WIFIService receiveMsgService;  int IntentID=0;ServiceConnection sc;boolean state;@Overrideprotected void onCreate(Bundle savedInstanceState) {super.onCreate(savedInstanceState);setContentView(R.layout.activity_main);sc=new ServiceConnection() {@Overridepublic void onServiceDisconnected(ComponentName name) {// TODO Auto-generated method stub}@Overridepublic void onServiceConnected(ComponentName name,  IBinder service) {// TODO Auto-generated method stubreceiveMsgService = ((WIFIService.MyBinder) service)  .getService();  receiveMsgService.setOnGetConnectState(new GetConnectState() { // 添加接口实例获取连接状态  @Override  public void GetState(int id) {  if (IntentID != id) { // 如果当前连接状态与广播服务返回的状态不同才进行通知显示  IntentID = id;  if (IntentID==0) {// 已连接  handler.sendEmptyMessage(0);  } else if(IntentID==1){// 未连接  handler.sendEmptyMessage(1);  }  else if(IntentID==2){handler.sendEmptyMessage(2);}}  }  });}};}public void bind(View view){startService(new Intent(MainActivity.this,WIFIService.class));bindService(new Intent(MainActivity.this, WIFIService.class), sc, getApplicationContext().BIND_AUTO_CREATE);state = true;}public void unbind(View view){if(state ){unbindService(sc);state = false;}}public void start(View view){}public void stop(View view){}@Override  protected void onDestroy()  {  // TODO Auto-generated method stub  super.onDestroy();  if(state){unbindService(sc);state = false;} }  Handler handler = new Handler() {  public void handleMessage(Message msg) {  switch (msg.what) {  case 0:Toast.makeText(MainActivity.this, "网络未经连接" ,Toast.LENGTH_LONG).show(); break;case 1:// 已连接  Toast.makeText(MainActivity.this, "WIFI已经连接" ,Toast.LENGTH_LONG).show();  break;  case 2:// 未连接  Toast.makeText(MainActivity.this, "3G已连接" ,Toast.LENGTH_LONG).show();  break;  default:  break;  }  ;  };  };  }