BroadcastReceiver获取手机网络状态

public class NetReceiver extends BroadcastReceiver {

	/**
	 * 枚举网络状态 NET_NO：没有网络 NET_2G:2g网络 NET_3G：3g网络 NET_4G：4g网络 NET_WIFI：wifi
	 * NET_UNKNOWN：未知网络
	 */
	public static enum NetState {
		NET_NO, NET_2G, NET_3G, NET_4G,NET_WIFI, NET_MOBILE, NET_UNKNOWN
	};

	public static List<NetEventHandle> ehList = new ArrayList<NetEventHandle>();

	public static interface NetEventHandle {
		/**
		 * 网络状态码
		 * 
		 * @param netCode
		 */
		void netState(NetState netCode);
	}

	@Override
	public void onReceive(Context context, Intent intent) {

		// 向所有实现接口的activity传递消息
		for (NetEventHandle e : ehList) {
			e.netState(isConnected(context));
		}

	}

	/**
	 * 判断当前是否网络连接
	 * 
	 * @param context
	 * @return 状态码
	 */
	public NetState isConnected(Context context) {
		NetState stateCode = NetState.NET_NO;
		ConnectivityManager cm = (ConnectivityManager) context.getSystemService(Context.CONNECTIVITY_SERVICE);
		NetworkInfo ni = cm.getActiveNetworkInfo();
		if (ni != null && ni.isConnectedOrConnecting()) {
			switch (ni.getType()) {
			case ConnectivityManager.TYPE_WIFI:
				stateCode = NetState.NET_WIFI;
				break;
			case ConnectivityManager.TYPE_MOBILE:
				switch (ni.getSubtype()) {
				case TelephonyManager.NETWORK_TYPE_GPRS: // 联通2g
				case TelephonyManager.NETWORK_TYPE_CDMA: // 电信2g
				case TelephonyManager.NETWORK_TYPE_EDGE: // 移动2g
				case TelephonyManager.NETWORK_TYPE_1xRTT:
				case TelephonyManager.NETWORK_TYPE_IDEN:
					stateCode = NetState.NET_2G;
					break;
				case TelephonyManager.NETWORK_TYPE_EVDO_A: // 电信3g
				case TelephonyManager.NETWORK_TYPE_UMTS:
				case TelephonyManager.NETWORK_TYPE_EVDO_0:
				case TelephonyManager.NETWORK_TYPE_HSDPA:
				case TelephonyManager.NETWORK_TYPE_HSUPA:
				case TelephonyManager.NETWORK_TYPE_HSPA:
				case TelephonyManager.NETWORK_TYPE_EVDO_B:
					// case TelephonyManager.NETWORK_TYPE_EHRPD:
					// case TelephonyManager.NETWORK_TYPE_HSPAP:
					stateCode = NetState.NET_3G;
					break;
				// case TelephonyManager.NETWORK_TYPE_LTE:
				// stateCode = NetState.NET_4G;
				// break;
				default:
					stateCode = NetState.NET_MOBILE;
				}
				break;
			default:
				stateCode = NetState.NET_UNKNOWN;
			}

		}
		return stateCode;
	}

}

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