private void OnSerachChange(object sender, SearchView.QueryTextChangeEventArgs e)
        {
            var dataset = locationDb.GetLocationsAsync().Result;

            if (string.IsNullOrWhiteSpace(e.NewText))
            {
                LocationAdapter myAdapter = new LocationAdapter(this, dataset);
                listView.Adapter = myAdapter;
            }
            else
            {
                LocationAdapter myAdapter = new LocationAdapter(this, dataset.Where(us => us.Name.ToLower().StartsWith(e.NewText.ToLower())).ToList());
                listView.Adapter = myAdapter;
            }
        }
        protected override void OnCreate(Bundle savedInstanceState)
        {
            base.OnCreate(savedInstanceState);

            // check if user is login
            if (App.username == null)
            {
                Intent ints = new Intent(this, typeof(LoginActivity));
                StartActivity(ints);
            }

            SetContentView(Resource.Layout.locationPage);

            // on logout button click
            FindViewById <Button>(Resource.Id.btnLocationLogout)
            .Click += (s, arg) =>
            {
                App.username = null;
                Intent ints = new Intent(this, typeof(LoginActivity));
                StartActivity(ints);
            };

            // on checkout button click
            FindViewById <Button>(Resource.Id.btnLoactionCheckout)
            .Click += (s, arg) =>
            {
                Intent ints = new Intent(this, typeof(CheckoutActivity));
                StartActivity(ints);
            };

            // Create your application here
            locationDb = new LocationDataBase(SharedHelper.DbPath);

            //var checkout = FindViewById<>(Resource.Id.checkout);
            listView    = FindViewById <ListView>(Resource.Id.listView1);
            searchView1 = FindViewById <SearchView>(Resource.Id.searchView1);

            LocationAdapter lp = new LocationAdapter(this, locationDb.GetLocationsAsync().Result);

            listView.Adapter             = lp;
            listView.ItemClick          += OnListClicked;
            searchView1.QueryTextChange += OnSerachChange;
        }