android检测网络状态

/**
* 检测当的网络（WLAN、3G/2G）状态
*
* @param context Context
* @return true 表示网络可用
*/
public static boolean isNetworkAvailable(Context context) {
ConnectivityManager connectivity = (ConnectivityManager) context
.getSystemService(Context.CONNECTIVITY_SERVICE);
if (connectivity != null) {
NetworkInfo info = connectivity.getActiveNetworkInfo();
//Log.i(TAG, info.getSubtypeName() + "===" + info.getSubtype() + "===" + info.getTypeName() + "====" + info.getType());
//info在没有网络时为null
//info.getType()返回网络类型：ConnectivityManager.TYPE_MOBILE或者ConnectivityManager.TYPE_WIFI
return info != null && info.isConnected();
}
return false;
}

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