在MultiBinding命令參數中包含綁定對象

我試圖使用<MultiBinding>將兩個參數傳遞給ViewModel的命令，但遇到問題讓XAML解析器接受我的嘗試。在MultiBinding命令參數中包含綁定對象

請考慮以下列表視圖，該視圖包含在我的UserControl中，它綁定到一組Ticket對象。

<ListView x:Name="lvTicketSummaries" 
        ItemsSource="{Binding TicketSummaries}" 
        ItemContainerStyle="{DynamicResource ResourceKey=ListViewItem}" 
        IsSynchronizedWithCurrentItem="True">

各自的風格ListViewItem

<Style x:Key="ListViewItem" TargetType="{x:Type ListViewItem}"> 
    <Setter Property="ContextMenu" Value="{DynamicResource ResourceKey=cmListViewItem}"/> 
    <!-- A load of irrelevant stuff -> 
</Style>

和引用ContextMenu項目在我的查詢的源坐鎮;

<!-- ContextMenu DataContext bound to UserControls view model so it can access 'Agents' ObservableCollection -->  
<ContextMenu x:Key="cmListViewItem" DataContext="{Binding RelativeSource={RelativeSource AncestorType={x:Type UserControl}}, Path=DataContext}"> 
    <MenuItem Header="Send as Notification" ItemsSource="{Binding Path=Agents}"> 
     <MenuItem.ItemContainerStyle> 
      <Style TargetType="{x:Type MenuItem}"> 
       <!-- Display the name of the agent (this works) --> 
       <Setter Property="Header" Value="{Binding Path=Name}"/> 
       <!-- Set the command to that of one on usercontrols viewmodel (this works) --> 
       <Setter Property="Command" Value="{Binding RelativeSource={RelativeSource AncestorType={x:Type ContextMenu}}, Path=DataContext.SendTicketNotification}" /> 
       <Setter Property="CommandParameter"> 
        <Setter.Value> 
         <MultiBinding Converter="{StaticResource ResourceKey=TicketNotificationParameterConverter}"> 
          <MultiBinding.Bindings> 
           <!-- This SHOULD be the Agent object I clicked on to trigger the Command. This does NOT work, results in either exception or 'UnsetValue' --> 
           <Binding Source="{Binding}" /> 
           <!-- Also pass in the Ticket item that was clicked on to open the context menu, this works fine --> 
           <Binding RelativeSource="{RelativeSource AncestorType={x:Type ListView}}" Path="SelectedItem" /> 
          </MultiBinding.Bindings> 
         </MultiBinding> 
        </Setter.Value> 
       </Setter> 
      </Style> 
     </MenuItem.ItemContainerStyle> 
    </MenuItem> 
</ContextMenu>

所以這裏是我試圖做的;

上下文菜單中有一個單一的項目「發送票據爲通知」的選擇時，列出了所有可用Agents可以接收所述通知。這工作。

當我點擊這些代理選一個，我想上下文菜單項，同時發送的ticket項目被點擊從listview，要顯示快捷菜單（這工作），我從選擇的Agent項目上下文菜單。我雖然已經在上下文菜單中的實際的建立似乎有些什麼複雜，我與MultiBinding

<MultiBinding Converter="{StaticResource ResourceKey=TicketNotificationParameterConverter}"> 
         <MultiBinding.Bindings> 
          <!-- This works, it sends the Ticket object to the Converter --> 
          <Binding RelativeSource="{RelativeSource AncestorType={x:Type ListView}}" Path="SelectedItem" /> 
          <!-- This caused an exception saying that I can only set 'Path' property on DependencyProperty types --> 
          <Binding Path="{Binding}" /> 
         </MultiBinding.Bindings> 
        </MultiBinding>

現在半實現了這一點。 MultiBinding參數之一的實際規格應該是綁定到點擊的ContextMenu.MenuItem的實際項目，這似乎是一個非常簡單的命令。上下文菜單正確地列出了所有Agent，所以我認爲只需要簡單地要求將當前對象作爲命令參數發送。我也嘗試過;

<Binding RelativeSource={RelativeSource AncestorType={x:Type MenuItem}} Path="SelectedItem" />

以及

<Binding RelativeSource={RelativeSource AncestorType={x:Type ContextMenu}} Path="SelectedItem" />

但所有的被髮送到參數轉換爲UnsetValue

謝謝你的時間，你可能有任何建議。

來源

2011-04-09 user407356

此行是奇數：

<Binding Path="{Binding}" />

是當前的DataContext這就夠了，因爲這將查找當前的DataContext這實際上是不是字符串畢竟東西路徑的字符串？非常有意義。

你是不是要這樣做，而是綁定到DataContext？

<Binding />

來源

2011-05-03 22:37:12

在MultiBinding命令參數中包含綁定對象

回答

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