android 检查网络状态

package com.bingo.net;

import android.app.Activity;
import android.content.Context;
import android.net.ConnectivityManager;
import android.net.NetworkInfo;

public class NetworkState {
	/**

	 * 

	 * @param activity

	 * @return false 为没有可用网络  true 为当前网络正常

	 */

	public static boolean hasInternet(Activity activity) {

	ConnectivityManager manager = (ConnectivityManager) activity

	.getSystemService(Context.CONNECTIVITY_SERVICE);

	NetworkInfo info = manager.getActiveNetworkInfo();

	if (info == null || !info.isAvailable()) {

	return false;

	}

	if (info.isRoaming()) {

	return true;

	}

	return true;

	}
}