Android如何检测网络的类型为3G、2G、wap、wifi

    /** 没有网络 */
    public static final int NETWORKTYPE_INVALID = 0;

    /** wap网络 */
    public static final int NETWORKTYPE_WAP = 1;

    /** 2G网络 */
    public static final int NETWORKTYPE_2G = 2;

    /** 3G和3G以上网络，或统称为快速网络 */
    public static final int NETWORKTYPE_3G = 3;

    /** wifi网络 */
    public static final int NETWORKTYPE_WIFI = 4;

private static boolean isFastMobileNetwork(Context context) {
TelephonyManager telephonyManager = (TelephonyManager)context.getSystemService(Context.TELEPHONY_SERVICE);
    switch (telephonyManager.getNetworkType()) {
        case TelephonyManager.NETWORK_TYPE_1xRTT:
            return false; // ~ 50-100 kbps
        case TelephonyManager.NETWORK_TYPE_CDMA:
            return false; // ~ 14-64 kbps
        case TelephonyManager.NETWORK_TYPE_EDGE:
            return false; // ~ 50-100 kbps
        case TelephonyManager.NETWORK_TYPE_EVDO_0:
            return true; // ~ 400-1000 kbps
        case TelephonyManager.NETWORK_TYPE_EVDO_A:
            return true; // ~ 600-1400 kbps
        case TelephonyManager.NETWORK_TYPE_GPRS:
            return false; // ~ 100 kbps
        case TelephonyManager.NETWORK_TYPE_HSDPA:
            return true; // ~ 2-14 Mbps
        case TelephonyManager.NETWORK_TYPE_HSPA:
            return true; // ~ 700-1700 kbps
        case TelephonyManager.NETWORK_TYPE_HSUPA:
            return true; // ~ 1-23 Mbps
        case TelephonyManager.NETWORK_TYPE_UMTS:
            return true; // ~ 400-7000 kbps
        case TelephonyManager.NETWORK_TYPE_EHRPD:
            return true; // ~ 1-2 Mbps
        case TelephonyManager.NETWORK_TYPE_EVDO_B:
            return true; // ~ 5 Mbps
        case TelephonyManager.NETWORK_TYPE_HSPAP:
            return true; // ~ 10-20 Mbps
        case TelephonyManager.NETWORK_TYPE_IDEN:
            return false; // ~25 kbps
        case TelephonyManager.NETWORK_TYPE_LTE:
            return true; // ~ 10+ Mbps
        case TelephonyManager.NETWORK_TYPE_UNKNOWN:
            return false;
        default:
            return false;
        }
    }

/**
     * 获取网络状态，wifi,wap,2g,3g.
     *
     * @param context 上下文
     * @return int 网络状态 {@link #NETWORKTYPE_2G},{@link #NETWORKTYPE_3G},          *{@link #NETWORKTYPE_INVALID},{@link #NETWORKTYPE_WAP}* <p>{@link #NETWORKTYPE_WIFI}
     */

    public static int getNetWorkType(Context context) {

        ConnectivityManager manager = (ConnectivityManager) context.getSystemService(Context.CONNECTIVITY_SERVICE);
        NetworkInfo networkInfo = manager.getActiveNetworkInfo();

        if (networkInfo != null && networkInfo.isConnected()) {
            String type = networkInfo.getTypeName();

            if (type.equalsIgnoreCase("WIFI")) {
                mNetWorkType = NETWORKTYPE_WIFI;
            } else if (type.equalsIgnoreCase("MOBILE")) {
                String proxyHost = android.net.Proxy.getDefaultHost();

                mNetWorkType = TextUtils.isEmpty(proxyHost)
                        ? (isFastMobileNetwork(context) ? NETWORKTYPE_3G : NETWORKTYPE_2G)
                        : NETWORKTYPE_WAP;
            }
        } else {
            mNetWorkType = NETWORKTYPE_INVALID;
        }

        return mNetWorkType;
    }