WP7中的ListBox数据绑定有关问题

System.Collections.ObjectModel.ObservableCollection<GameBoxClass.GameNum> query = new System.Collections.ObjectModel.ObservableCollection<GameBoxClass.GameNum>();            for (int i = 0; i < 5; i++)            {                query.Add(new GameBoxClass.GameNum                {                    Account =  i + "号",                    Password = "111",                    PasswordCard = new System.Windows.Media.Imaging.BitmapImage(new Uri("/Images/wow.jpg", UriKind.RelativeOrAbsolute))                });            }            AccountList.ItemsSource = query;

<ListBox  x:Name="AccountList" Grid.Row="1" >                <ListBox.ItemTemplate>                    <DataTemplate>                        <TextBlock Text="{Binding Path=Account, Mode=TwoWay}" FontFamily="微软雅黑" Foreground="Black"></TextBlock>                    </DataTemplate>                </ListBox.ItemTemplate>            </ListBox>