Location Services Check

// if gps is enabled and network location is disabled
// note, GPS can be slow to obtain location data but is more accurate
if (locationProviders.contains("gps") && !locationProviders.contains("network")) {

    // build a new alert dialog to inform the user that they only have GPS location services
    new AlertDialog.Builder(this)

            //set the message to display to the user
            .setMessage("Only GPS Enabled")

            // add the 'positive button' to the dialog and give it a
            // click listener
            .setPositiveButton("Enable Location Services",
                    new DialogInterface.OnClickListener() {
                        // setup what to do when clicked
                        public void onClick(DialogInterface dialog,
                                int id) {
                            // start the settings menu on the correct
                            // screen for the user
                            startActivity(new Intent(
                                    Settings.ACTION_LOCATION_SOURCE_SETTINGS));
                        }

                        // add the 'negative button' to the dialog and
                        // give it a click listener
                    })
            .setNegativeButton("Close",
                    new DialogInterface.OnClickListener() {
                        // setup what to do when clicked
                        public void onClick(DialogInterface dialog,
                                int id) {
                            // remove the dialog
                            dialog.cancel();
                        }

                        // finish creating the dialog and show to the
                        // user
                    }).create().show();

    // if gps is disabled and network location services are enabled
        // network services are quick and fairly accurate, we are happy to use them
} else if (!locationProviders.contains("gps") && locationProviders.contains("network")) {

    // do nothing at present...

    // if gps is disabled and network location services are disabled
        // the user has no location services and must enable something
} else if (!locationProviders.contains("gps") && !locationProviders.contains("network")) {

    // build a new alert dialog to inform the user that they have no
    // location services enabled
    new AlertDialog.Builder(this)

            //set the message to display to the user
            .setMessage("No Location Services Enabled")

            // add the 'positive button' to the dialog and give it a
            // click listener
            .setPositiveButton("Enable Location Services",
                    new DialogInterface.OnClickListener() {
                        // setup what to do when clicked
                        public void onClick(DialogInterface dialog,
                                int id) {
                            // start the settings menu on the correct
                            // screen for the user
                            startActivity(new Intent(
                                    Settings.ACTION_LOCATION_SOURCE_SETTINGS));
                        }

                        // add the 'negative button' to the dialog and
                        // give it a click listener
                    })
            .setNegativeButton("Close",
                    new DialogInterface.OnClickListener() {
                        // setup what to do when clicked
                        public void onClick(DialogInterface dialog,
                                int id) {
                            // remove the dialog
                            dialog.cancel();
                        }

                        // finish creating the dialog and show to the
                        // user
                    }).create().show();
}