Android设备上如何检查wifi或3g网络

Question

Here, my android device supports both wifi and 3g. At particular time which network is available on this device. Because my requirement is when 3g is available I have to upload small amount of data. when wifi is available entire data have to upload. So, I have to check connection is wifi or 3g. Please help me. Thanks in advance.

Answer 1

I use this:

/**
 * Checks if we have a valid Internet Connection on the device.
 * @param ctx
 * @return True if device has internet
 *
 * Code from: http://www.androidsnippets.org/snippets/131/
 */
public static boolean haveInternet(Context ctx) {

    NetworkInfo info = (NetworkInfo) ((ConnectivityManager) ctx
            .getSystemService(Context.CONNECTIVITY_SERVICE)).getActiveNetworkInfo();

    if (info == null || !info.isConnected()) {
        return false;
    }
    if (info.isRoaming()) {
        // here is the roaming option you can change it if you want to
        // disable internet while roaming, just return false
        return false;
    }
    return true;
}

You also need

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

in AndroidMainfest.xml

To get the network type you can use this code snippet:

ConnectivityManager conMan = (ConnectivityManager) getSystemService(Context.CONNECTIVITY_SERVICE);

//mobile
State mobile = conMan.getNetworkInfo(0).getState();

//wifi
State wifi = conMan.getNetworkInfo(1).getState();

and then use it like that:

if (mobile == NetworkInfo.State.CONNECTED || mobile == NetworkInfo.State.CONNECTING) {
    //mobile
} else if (wifi == NetworkInfo.State.CONNECTED || wifi == NetworkInfo.State.CONNECTING) {
    //wifi
}

To get the type of the mobile network I would try TelephonyManager#getNetworkType or NetworkInfo#getSubtypeName

Answer 2

You need to add below permission in android manifest file:

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

After that you can use below functions to check wifi or mobile network is connected or not

public static boolean isWifiConnected(Context context) {
        ConnectivityManager connManager = (ConnectivityManager) context
                .getSystemService(Context.CONNECTIVITY_SERVICE);
        NetworkInfo netInfo = connManager.getNetworkInfo(ConnectivityManager.TYPE_WIFI);
        return ((netInfo != null) && netInfo.isConnected());
    }

public static boolean isMobileConnected(Context context) {
        ConnectivityManager connManager = (ConnectivityManager) context
                .getSystemService(Context.CONNECTIVITY_SERVICE);
        NetworkInfo netInfo = connManager.getNetworkInfo(ConnectivityManager.TYPE_MOBILE);
        return ((netInfo != null) && netInfo.isConnected());
    }

Some references from developer.android.com are:

1. https://developer.android.com/reference/android/net/ConnectivityManager.html
2. https://developer.android.com/reference/android/net/NetworkInfo.html
3. https://developer.android.com/reference/android/net/ConnectivityManager.html#getActiveNetworkInfo()

Answer 3

First get a reference to the ConnectivityManager and then check the Wifi and 3G status of the device. You'll need the ACCESS_NETWORK_STATE permission to use this service.

    ConnectivityManager connManager = (ConnectivityManager) getSystemService(CONNECTIVITY_SERVICE);
    NetworkInfo mWifi = connManager.getNetworkInfo(ConnectivityManager.TYPE_WIFI);
    NetworkInfo mMobile = connManager.getNetworkInfo(ConnectivityManager.TYPE_MOBILE);

    if (mWifi.isAvailable() == true) {
        return "Connected to WiFi";
    } else if (mMobile.isAvailable() == true) {
        return "Connected to Mobile Network";
    } else return "No internet Connection"

Answer 4

You can use this method to check whether your internet connection is 2G, 3G or 4G :

public String getNetworkClass(Context context) {
    TelephonyManager mTelephonyManager = (TelephonyManager)
        context.getSystemService(Context.TELEPHONY_SERVICE);
    int networkType = mTelephonyManager.getNetworkType();
    switch (networkType) {
        case TelephonyManager.NETWORK_TYPE_GPRS:
        case TelephonyManager.NETWORK_TYPE_EDGE:
        case TelephonyManager.NETWORK_TYPE_CDMA:
        case TelephonyManager.NETWORK_TYPE_1xRTT:
        case TelephonyManager.NETWORK_TYPE_IDEN:
            return "2G";
        case TelephonyManager.NETWORK_TYPE_UMTS:
        case TelephonyManager.NETWORK_TYPE_EVDO_0:
        case TelephonyManager.NETWORK_TYPE_EVDO_A:
        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:
            return "3G";
        case TelephonyManager.NETWORK_TYPE_LTE:
            return "4G";
        default:
            return "Unknown";
    }
}

And using following method you can check if internet is available or not , and get whether you are accessing the internet via a mobile network or WiFi :

public String getNetworkType(Context context){
    String networkType = null;
    ConnectivityManager connectivityManager = (ConnectivityManager) context.getSystemService(Context.CONNECTIVITY_SERVICE);
    NetworkInfo activeNetwork = connectivityManager.getActiveNetworkInfo();
    if (activeNetwork != null) { // connected to the internet
        if (activeNetwork.getType() == ConnectivityManager.TYPE_WIFI) {
                networkType = "WiFi";
        } else if (activeNetwork.getType() == ConnectivityManager.TYPE_MOBILE) {
            networkType = "Mobile";
        }
    } else {
        // not connected to the internet
    }
    return networkType;
}