ListView没有在PropertyChanged事件上更新

我有以下代码，但问题是，PropertyChanged总是空的，当我试图触发它。为什么会这样，我怎样才能绕过这个问题?

以编程方式创建ListView并为其添加绑定:

            ListView listView = new ListView();
            listView.Height = 203;
            listView.Width = 501;
            listView.Margin = new Thickness(0, 0, 0, 0);
            Grid.SetRow(listView, 1);
            Grid.SetColumn(listView, 0);
            mainGrid.Children.Add(listView);
            GridView myGridView = new GridView();
            myGridView.AllowsColumnReorder = true;
            System.Windows.Controls.GridViewColumn gvc1 = new System.Windows.Controls.GridViewColumn();
            gvc1.DisplayMemberBinding = new Binding("Date");
            gvc1.Header = "Date";
            gvc1.Width = 100;
            myGridView.Columns.Add(gvc1);
            System.Windows.Controls.GridViewColumn gvc2 = new System.Windows.Controls.GridViewColumn();
            gvc2.DisplayMemberBinding = new Binding("Application");
            gvc2.Header = "Application";
            gvc2.Width = 100;
            myGridView.Columns.Add(gvc2);
            System.Windows.Controls.GridViewColumn gvc3 = new System.Windows.Controls.GridViewColumn();
            gvc3.DisplayMemberBinding = new Binding("Message");
            gvc3.Header = "Message";
            gvc3.Width = 100;
            myGridView.Columns.Add(gvc3);
            listView.View = myGridView;
            // Create a new binding object and set the binding of this list view to it.
            //rows = new ObservableCollection<Row>();
            rows = new Rows();
            // Create a background worker to update the rows every second.
            BackgroundWorker bgworker = new BackgroundWorker();
            bgworker.WorkerReportsProgress = true;
            bgworker.DoWork += (doWorkSender, doWorkEventArguments) => {
                for (int i = 0; i < 1000000; i++) {
                    Thread.Sleep(1000);
                    bgworker.ReportProgress(i);
                }
                doWorkEventArguments.Result = null;
            };
            bgworker.ProgressChanged += (progressChangedSender, progressChangedEventArguments) => {
                rows.Add(new Row { Date = DateTime.Now.ToString(), Application = "Application", Message = "This is a sample message." });
            };
            bgworker.RunWorkerAsync();
            listView.DataContext = rows;
            Binding myBinding = new Binding();
            myBinding.Source = rows;
            listView.SetBinding(ItemsControl.ItemsSourceProperty, myBinding);

Row和Rows类:

    public class Row {
        public string Date { set; get; }
        public string Application { set; get; }
        public string Message { set; get; }
    }
    public class Rows : IEnumerable<Row>, INotifyPropertyChanged {
        public List<Row> rowList { get; private set; }
        public event PropertyChangedEventHandler PropertyChanged;
        public Rows() {
            rowList = new List<Row>();
        }
        public void Add(Row item) {
            rowList.Add(item);
            if (PropertyChanged != null) {
                PropertyChanged(this, new PropertyChangedEventArgs("rowList"));
            }
            else {
                Console.WriteLine("PropertyChanged is null.");
            }
        }
        public IEnumerator<Row> GetEnumerator() {
            return rowList.GetEnumerator();
        }
        System.Collections.IEnumerator System.Collections.IEnumerable.GetEnumerator() {
            return GetEnumerator();
        }
    }

将rows对象声明为rows类型:

Rows rows;