Detect if Android device has Internet connection
I need to tell if my device has Internet connection or not. I found many answers like:
private boolean isNetworkAvailable() {
ConnectivityManager connectivityManager
= (ConnectivityManager) getSystemService(Context.CONNECTIVITY_SERVICE);
NetworkInfo activeNetworkInfo = connectivityManager.getActiveNetworkInfo();
return activeNetworkInfo != null;
}
(Taken from Detect whether there is an Internet connection available on Android.)
But this is not right, for example if I'm connected to a wireless network which doesn't have Internet access, this method will return true… Is there a way to tell if the device has Internet connection and not if it is only connected to something?
You are right. The code you've provided only checks if there is a network connection. The best way to check if there is an active Internet connection is to try and connect to a known server via http.
public static boolean hasActiveInternetConnection(Context context) {
if (isNetworkAvailable(context)) {
try {
HttpURLConnection urlc = (HttpURLConnection) (new URL("http://www.google.com").openConnection());
urlc.setRequestProperty("User-Agent", "Test");
urlc.setRequestProperty("Connection", "close");
urlc.setConnectTimeout(1500);
urlc.connect();
return (urlc.getResponseCode() == 200);
} catch (IOException e) {
Log.e(LOG_TAG, "Error checking internet connection", e);
}
} else {
Log.d(LOG_TAG, "No network available!");
}
return false;
}
Of course you can substitute the http://www.google.com
URL for any other server you want to connect to, or a server you know has a good uptime.
As Tony Cho also pointed out in this comment below, make sure you don't run this code on the main thread, otherwise you'll get a NetworkOnMainThread exception (in Android 3.0 or later). Use an AsyncTask or Runnable instead.
If you want to use google.com you should look at Jeshurun's modification. In his answer he modified my code and made it a bit more efficient. If you connect to
HttpURLConnection urlc = (HttpURLConnection)
(new URL("http://clients3.google.com/generate_204")
.openConnection());
and then check the responsecode for 204
return (urlc.getResponseCode() == 204 && urlc.getContentLength() == 0);
then you don't have to fetch the entire google home page first.
I have modified THelper's answer slightly, to use a known hack that Android already uses to check if the connected WiFi network has Internet access. This is a lot more efficient over grabbing the entire Google home page. See here and here for more info.
public static boolean hasInternetAccess(Context context) {
if (isNetworkAvailable(context)) {
try {
HttpURLConnection urlc = (HttpURLConnection)
(new URL("http://clients3.google.com/generate_204")
.openConnection());
urlc.setRequestProperty("User-Agent", "Android");
urlc.setRequestProperty("Connection", "close");
urlc.setConnectTimeout(1500);
urlc.connect();
return (urlc.getResponseCode() == 204 &&
urlc.getContentLength() == 0);
} catch (IOException e) {
Log.e(TAG, "Error checking internet connection", e);
}
} else {
Log.d(TAG, "No network available!");
}
return false;
}
public boolean isInternetWorking() {
boolean success = false;
try {
URL url = new URL("https://google.com");
HttpURLConnection connection = (HttpURLConnection) url.openConnection();
connection.setConnectTimeout(10000);
connection.connect();
success = connection.getResponseCode() == 200;
} catch (IOException e) {
e.printStackTrace();
}
return success;
}
return true if internet is actually available
Make sure you have these two permission
<uses-permission android:name="android.permission.INTERNET"/>
<uses-permission android:name="android.permission.ACCESS_NETWORK_STATE"/>
if http does not work its because of the new android security they donot allow plain text communication now. for now just to by pass it.
android:usesCleartextTraffic="true"
I would recommend to ping your own server. In this way you are more confident that you have internet and your web server is also working. (for cases like when you have internet but your server is down)