这里，我采用Service+BroadcastReceiver的形式实时监听网络变化。
原理是程序在背后启一个Service，在Service中注册一个广播，当网络变化时会产生一个ConnectivityManager.CONNECTIVITY_ACTION事件，只要监听这个事件就可以了。代码如下：
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.IBinder;
import android.util.Log;
public class NetworkStateService extends Service{
private static final String tag="tag";
private ConnectivityManager connectivityManager;
private NetworkInfo info;
private BroadcastReceiver mReceiver = new BroadcastReceiver() {
@Override
public void onReceive(Context context, Intent intent) {
String action = intent.getAction();
if (action.equals(ConnectivityManager.CONNECTIVITY_ACTION)) {
Log.d(tag, "网络状态已经改变");
connectivityManager = (ConnectivityManager)getSystemService(Context.CONNECTIVITY_SERVICE);
info = connectivityManager.getActiveNetworkInfo();
if(info != null && info.isAvailable()) {
String name = info.getTypeName();
Log.d(tag, "当前网络名称：" + name);
//doSomething()
} else {
Log.d(tag, "没有可用网络");
//doSomething()
}
}
}
};
@Override
public IBinder onBind(Intent intent) {
// TODO Auto-generated method stub
return null;
}
@Override
public void onCreate() {
super.onCreate();
IntentFilter mFilter = new IntentFilter();
mFilter.addAction(ConnectivityManager.CONNECTIVITY_ACTION);
registerReceiver(mReceiver, mFilter);
}
@Override
public void onDestroy() {
super.onDestroy();
unregisterReceiver(mReceiver);
}
@Override
public int onStartCommand(Intent intent, int flags, int startId) {
return super.onStartCommand(intent, flags, startId);
}
}
别忘了在Manifast中配置这个Service：
<service android:enabled="true" android:name="com.reyo.util.NetworkStateService" />
还有权限：
<uses-permission android:name="android.permission.ACCESS_NETWORK_STATE" />
在必要的地方启动该Service即可：
Intent i=new Intent(context,NetworkStateService.class); startService(i);
另外附加几个 Android网络连接的判断
1）判断是否有网络连接
public boolean isNetworkConnected(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;
}
2）判断WIFI网络是否可用
public 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;
}
3）判断MOBILE网络是否可用
public boolean isMobileConnected(Context context) {
if (context != null) {
ConnectivityManager mConnectivityManager = (ConnectivityManager) context
.getSystemService(Context.CONNECTIVITY_SERVICE);
NetworkInfo mMobileNetworkInfo = mConnectivityManager
.getNetworkInfo(ConnectivityManager.TYPE_MOBILE);
if (mMobileNetworkInfo != null) {
return mMobileNetworkInfo.isAvailable();
}
}
return false;
}
4）获取当前网络连接的类型信息
public static int getConnectedType(Context context) {
if (context != null) {
ConnectivityManager mConnectivityManager = (ConnectivityManager) context
.getSystemService(Context.CONNECTIVITY_SERVICE);
NetworkInfo mNetworkInfo = mConnectivityManager.getActiveNetworkInfo();
if (mNetworkInfo != null && mNetworkInfo.isAvailable()) {
return mNetworkInfo.getType();
}
}
return -1;
}