Inv365Sortable.cs

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;

using System.Windows;
using System.ComponentModel;
using System.Windows.Data;
using System.Windows.Controls;

namespace CheckCasher
{
    abstract public class Inv365Sortable : Page
    {
        GridViewColumnHeader _lastHeaderClicked = null;
        ListSortDirection _lastDirection = ListSortDirection.Ascending;

        public void GridViewColumnHeaderClickedHandler(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 = getUpTemplate();
                          //Resources["HeaderTemplateArrowUp"] as DataTemplate;
                    }
                    else
                    {
                        headerClicked.Column.HeaderTemplate = getDownTemplate();
                          //Resources["HeaderTemplateArrowDown"] as DataTemplate;
                    }

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


                    _lastHeaderClicked = headerClicked;
                    _lastDirection = direction;
                }
            }

        }

        abstract public DataTemplate getUpTemplate();
        abstract public DataTemplate getDownTemplate();
        abstract public ListView getView();

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

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


    }
}