Checking Internet connection on Android

Question

I need to check Internet connection on Android app.

I'm using this code:

 ConnectivityManager cm = (ConnectivityManager) getSystemService(Context.CONNECTIVITY_SERVICE);
        NetworkInfo ni = cm.getActiveNetworkInfo();
        if (ni!=null && ni.isAvailable() && ni.isConnected()) {
            return true;
        } else {
            return false; 
        }

And cannot pass the next error:

The method getSystemService(String) is undefined for the type ConxsMTD

I tried using getContext().getSystemService and also failed with next error:

The method getContext() is undefined for the type ConxsMTD

Any idea what I'm doing wrong?

Answer 1

This doesn't fix your given example, but my example does work and is more simple (in my mind).

What you want to do is send a "ping" (if you want to call it that) to check the connection. If the connection completes, you know you are still connected. If you get an IOException or a NullPointerException , then you probably timed out and are not connected anymore.

try {
    URL url = new URL("http://www.google.com");
    HttpURLConnection urlConnect = (HttpURLConnection) url.openConnection();
    urlConnect.setConnectTimeout(1000);
    urlConnect.getContent();
    System.out.println("Connection established.");
} catch (NullPointerException np) {
    np.printStackTrace();
} catch (IOException io) {
    io.printStackTrace();
}

Answer 2

Use this snippet, I use it in every project:

public static boolean checkNetworkState(Context context) {
    ConnectivityManager conMgr = (ConnectivityManager) context.getSystemService(Context.CONNECTIVITY_SERVICE);
    NetworkInfo infos[] = conMgr.getAllNetworkInfo();
    for (NetworkInfo info : infos) {
        if (info.getState() == State.CONNECTED)
            return true;
    }
    return false;
}

So, you only must pass getApplicationContext() to this method like boolean hasConnection = checkNetworkState(getApplicationContext());