How to check internet access on Android? InetAddress never times out

Question

I got a AsyncTask that is supposed to check the network access to a host name. But the doInBackground() is never timed out. Anyone have a clue?

Answer 1

If the device is in airplane mode (or presumably in other situations where there's no available network), cm.getActiveNetworkInfo() will be null, so you need to add a null check.

Modified (Eddie's solution) below:

public boolean isOnline() {
    ConnectivityManager cm =
        (ConnectivityManager) getSystemService(Context.CONNECTIVITY_SERVICE);
    NetworkInfo netInfo = cm.getActiveNetworkInfo();
    return netInfo != null && netInfo.isConnectedOrConnecting();
}

Also add the following permission to the AndroidManifest.xml:

One other small point, if you absolutely need a network connection at the given point in time, then it might be better to use netInfo.isConnected() rather than netInfo.isConnectedOrConnecting. I guess this is up to the individual use-case however.