[android] How to check currently internet connection is available or not in android

This will show an dialog error box if there is not network connectivity

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

    if (networkInfo != null && networkInfo.isConnected()) {
        // fetch data
    } else {
        new AlertDialog.Builder(this)
            .setTitle("Connection Failure")
            .setMessage("Please Connect to the Internet")
            .setPositiveButton(android.R.string.ok, new DialogInterface.OnClickListener() {
                public void onClick(DialogInterface dialog, int which) {
                }
            })
            .setIcon(android.R.drawable.ic_dialog_alert)
            .show();
    }