Listbox數據綁定NewItemPlaceholder

我有一個可觀察的集合綁定到列表框。收集有2項，但列表框中顯示3項（如2項，實際上是觀察集合併爲NewItemPlaceholder額外的項目。Listbox數據綁定NewItemPlaceholder

我希望它只顯示2項。

下面是我的XAML

<ListBox MinHeight="20" MinWidth="20" Name="MultipleSelectionsMultipleWagersListBox" Visibility="{Binding Path=Coupon.BarcodeText, Converter={StaticResource CouponBarcodeToVisibilityConverter1}, ConverterParameter=994450_994550}" Height="AUto" Width="Auto" VerticalAlignment="Stretch" HorizontalAlignment="Stretch" Margin="5" 
     ItemsSource="{Binding Path=BetViewModels}" Grid.Row="1" Grid.Column="1" > 
    <ListBox.ItemTemplate> 
     <DataTemplate> 
      <View:BetView DataContext="{Binding}" Name="ThisBet" Margin="5"/> 
     </DataTemplate> 
    </ListBox.ItemTemplate> 
</ListBox>

這裏是C＃

private ObservableCollection<BetViewModel> _betViewModels = new ObservableCollection<BetViewModel>(); 
    public ObservableCollection<BetViewModel> BetViewModels 
    { 
     get { return _betViewModels; } 
     set 
     { 
      if (Equals(value, _betViewModels)) return; 
      _betViewModels = value; 
      OnPropertyChanged("BetViewModels"); 
     } 
    }

這裏被填充betViewModels代碼：

var betViewModel = new BetViewModel { Bet = new Bet() }; 
betViewModel.Bet.SelectionName = "Chelsea"; 
betViewModel.Bet.Price = "4/9"; 
betViewModel.Bet.Market = "90 Minutes"; 
betViewModel.Bet.ExpectedOdd = DateTime.Now; 
BetViewModels.Add(betViewModel); 

betViewModel = new BetViewModel { Bet = new Bet() }; 
betViewModel.Bet.SelectionName = "Chelsea"; 
betViewModel.Bet.Price = "4/9"; 
betViewModel.Bet.Market = "90 Minutes"; 
betViewModel.Bet.ExpectedOdd = DateTime.Now; 
BetViewModels.Add(betViewModel);

如何從展示新項目的地方

在這裏的附加項目切換的，這是它的顯示的佔位符圖像

enter image description here