How to sort ListView by Column Using ObservableCollection

I am beginner at WPF. I am trying to sort (asc/desc) a listview by clicking a column. I have binded an observable collection to my listview. I have tried something I have found here http://ift.tt/1EfKH6W For some reason it doesn't work on me. My code is almost same within this link here. But I wrote it here anyways though sorry that it's a little bit long.

I made some search and many answer already suggests exactly what I did. So I guess I made some mistakes somewhere.

Here is WPF:

    <ListView Grid.Row="3" Name="lvPurchaseSummaryList" ItemsSource="{Binding purchaseSummaryCol, Mode=Default}" Width="1700" HorizontalAlignment="Left" GridViewColumnHeader.Click="purchaseSummaryListColumn_click">
        <ListView.View>
            <GridView>
                <GridViewColumn Width="100" DisplayMemberBinding="{Binding Path=originalName}" Header="Original Name" />
                <GridViewColumn Width="100" DisplayMemberBinding="{Binding Path=turkishName}" Header="Local Name"/>
 // List goes on like this...
            </GridView>
        </ListView.View>
</ListView>

Here is the class (almost same with msdn link):

public partial class PurchaseSummaryPage : Page
{
    GridViewColumnHeader _lastHeaderClicked = null;
    ListSortDirection _lastDirection = ListSortDirection.Ascending;
    public PurchaseSummaryPage()
    {
        InitializeComponent();  
    }

    void purchaseSummaryListColumn_click(object sender, RoutedEventArgs e)
    {
        GridViewColumnHeader headerClicked = e.OriginalSource as GridViewColumnHeader;
        ListSortDirection direction;

        if (headerClicked != null)
        {
            if (headerClicked.Role != GridViewColumnHeaderRole.Padding)
            {
                if (headerClicked != _lastHeaderClicked)
                {
                    direction = ListSortDirection.Ascending;
                }
                else
                {
                    if (_lastDirection == ListSortDirection.Ascending)
                    {
                        direction = ListSortDirection.Descending;
                    }
                    else
                    {
                        direction = ListSortDirection.Ascending;
                    }
                }

                string header = headerClicked.Column.Header as string;
                Sort(header, direction);

                if (direction == ListSortDirection.Ascending)
                {
                    headerClicked.Column.HeaderTemplate =
                      Resources["HeaderTemplateArrowUp"] as DataTemplate;
                }
                else
                {
                    headerClicked.Column.HeaderTemplate =
                      Resources["HeaderTemplateArrowDown"] as DataTemplate;
                }

                // Remove arrow from previously sorted header 
                if (_lastHeaderClicked != null && _lastHeaderClicked != headerClicked)
                {
                    _lastHeaderClicked.Column.HeaderTemplate = null;
                }


                _lastHeaderClicked = headerClicked;
                _lastDirection = direction;
            }
        }
    }


    private void Sort(string sortBy, ListSortDirection direction)
    {
        ICollectionView dataView =
          CollectionViewSource.GetDefaultView(lvPurchaseSummaryList.ItemsSource);

        dataView.SortDescriptions.Clear();
        SortDescription sd = new SortDescription(sortBy, direction);

        dataView.SortDescriptions.Add(sd);
        dataView.Refresh();
    }
}

And this is from main window with some example in it...

    public ObservableCollection<PurchaseSummary> purchaseSummaryCol { get; set; }

    public MainWindow()
    {
        InitializeComponent();
        purchaseSummaryCol = new ObservableCollection<PurchaseSummary>();
        purchaseSummaryCol.Add(new PurchaseSummary("100", "basd", "asd", "basd", "asd", "basd", "asd", "basd", "asd", new Pay(DateTime.Today, DateTime.Today, 3), new PayRestrict(), new Vod()));
        purchaseSummaryCol.Add(new PurchaseSummary("105", "asd", "basd", "asd", "basd", "asd", "basd", "asd", "basd", new Pay(DateTime.Today, DateTime.Today, 3), new PayRestrict(), new Vod()));
        purchaseSummaryCol.Add(new PurchaseSummary("101", "casd", "cbasd", "casd", "cbasd", "casd", "cbasd", "casd", "cbasd", new Pay(DateTime.Today, DateTime.Today, 3), new PayRestrict(), new Vod()));

        PurchaseSummaryPage purchaseSummaryPage = new PurchaseSummaryPage();
        purchaseSummaryPage.DataContext = this;
        AttachPageToFrame(_f, purchaseSummaryPage);
    }