1.注册一个广播接收器，监听网络状态
private void Start()
{
IntentFilter filter = new IntentFilter();
filter.addAction(ConnectivityManager.CONNECTIVITY_ACTION);
filter.addAction(WifiManager.WIFI_STATE_CHANGED_ACTION);
filter.addAction(WifiManager.NETWORK_STATE_CHANGED_ACTION);
this.registerReceiver(myBroadcastReceiver, filter);
}

2.取消注册广播器
private void Stop()
{
this.unregisterReceiver(myBroadcastReceiver);
}

3.新建监听类NetworkConnectChangedReceiver继承BroadcastReceiver

public class NetworkConnectChangedReceiver extends BroadcastReceiver
{
@Override
public void onReceive(Context context, Intent intent)
{
// 这个监听wifi的打开与关闭，与wifi的连接无关
if (WifiManager.WIFI_STATE_CHANGED_ACTION.equals(intent.getAction()))
{
int wifiState = intent.getIntExtra(WifiManager.EXTRA_WIFI_STATE, 0);
switch (wifiState)
{
case WifiManager.WIFI_STATE_ENABLED:
Log.e("APActivity", "WIFI_STATE_ENABLED");
break;
case WifiManager.WIFI_STATE_ENABLING:
Log.e("APActivity", "WIFI_STATE_ENABLING");
break;
case WifiManager.WIFI_STATE_DISABLED:
Log.e("APActivity", "WIFI_STATE_DISABLED");
break;
case WifiManager.WIFI_STATE_DISABLING:
Log.e("APActivity", "WIFI_STATE_DISABLING");
break;
}
}
// 这个监听wifi的连接状态即是否连上了一个有效无线路由，当上边广播的状态是WifiManager.WIFI_STATE_DISABLING，和WIFI_STATE_DISABLED的时候，根本不会接到这个广播。
// 在上边广播接到广播是WifiManager.WIFI_STATE_ENABLED状态的同时也会接到这个广播，当然刚打开wifi肯定还没有连接到有效的无线
if (WifiManager.NETWORK_STATE_CHANGED_ACTION.equals(intent.getAction()))
{
Parcelable parcelableExtra = intent.getParcelableExtra(WifiManager.EXTRA_NETWORK_INFO);
if (null != parcelableExtra)
{
NetworkInfo networkInfo = (NetworkInfo) parcelableExtra;
switch (networkInfo.getState())
{
case CONNECTED:
Log.e("APActivity", "CONNECTED");
break;
case CONNECTING:
Log.e("APActivity", "CONNECTING");
break;
case DISCONNECTED:
Log.e("APActivity", "DISCONNECTED");
break;
case DISCONNECTING:
Log.e("APActivity", "DISCONNECTING");
break;
case SUSPENDED:
Log.e("APActivity", "SUSPENDED");
break;
case UNKNOWN:
Log.e("APActivity", "UNKNOWN");
break;
default:
break;
}
}
}
// 这个监听网络连接的设置，包括wifi和移动数据的打开和关闭。
// 最好用的还是这个监听。wifi如果打开，关闭，以及连接上可用的连接都会接到监听。见log
// 这个广播的最大弊端是比上边两个广播的反应要慢，如果只是要监听wifi，我觉得还是用上边两个配合比较合适
if (ConnectivityManager.CONNECTIVITY_ACTION.equals(intent.getAction()))
{
NetworkInfo info = intent.getParcelableExtra(ConnectivityManager.EXTRA_NETWORK_INFO);
if (info != null)
{
StringBuilder sb = new StringBuilder();
sb.append("info.getTypeName() : " + info.getTypeName() + "\n");
sb.append("getSubtypeName() : " + info.getSubtypeName() + "\n");
sb.append("getState() : " + info.getState() + "\n");
sb.append("getDetailedState() : " + info.getDetailedState().name() + "\n");
sb.append("getDetailedState() : " + info.getExtraInfo() + "\n");
sb.append("getType() : " + info.getType());
Log.e("APActivity", sb.toString());
}
}
}
}

当网络连接接通的时候，是用的是Wifi或者3G网络。利用本文所述,可以实现记录何时使用的是Wifi，何时使用的是3G网络。

public void onReceive(Context context, Intent intent) {
String action = intent.getAction();
if (ConnectivityManager.CONNECTIVITY_ACTION.equals(action)) {
NetworkInfo ni = intent.getParcelableExtra(ConnectivityManager.EXTRA_NETWORK_INFO);
if (ni.getState() == State.CONNECTED && ni.getType() == ConnectivityManager.TYPE_WIFI) {
Log.v("kevin", "wifi connected");
} else if(ni.getState() == State.DISCONNECTED && ni.getType() == ConnectivityManager.TYPE_WIFI){
Log.v("kevin", "wifi disconnected");
}
}
}
}