當用作DataTemplate時用戶控件不呈現？

Question

我有一個用戶控件，我想用作ListBox中的DataTemplate。

這工作：

<ListBox> 
    <ListBox.ItemTemplate> 
     <DataTemplate> 
<Grid x:Name="Grid" Height="100" Width="880" Background="LightGray"> 
    <Grid.RowDefinitions> 
     <RowDefinition Height="24"/> 
     <RowDefinition Height="24"/> 
     <RowDefinition Height="24"/> 
     <RowDefinition Height="24"/> 
    </Grid.RowDefinitions> 
    <Grid.ColumnDefinitions> 
     <ColumnDefinition Width="190" /> 
     <ColumnDefinition Width="100" /> 
     <ColumnDefinition Width="100" /> 
     <ColumnDefinition Width="100" /> 
     <ColumnDefinition Width="190" /> 
     <ColumnDefinition Width="200" /> 
    </Grid.ColumnDefinitions> 
    <Label Grid.Column="0" Grid.Row="0">Client</Label> 
    <Label Grid.Column="0" Grid.Row="2">Contact</Label> 
    <Label Grid.Column="1" Grid.Row="0">Date Presentation</Label> 
    <Label Grid.Column="2" Grid.Row="0">Action</Label> 
    <Label Grid.Column="3" Grid.Row="0">Date Interview</Label> 
    <Label Grid.Column="3" Grid.Row="2">Time Interview</Label> 
    <Label Grid.Column="4" Grid.Row="0">Remarks</Label> 
    <Label Grid.Column="5" Margin="0,0,2,0">managed by</Label> 
    <ComboBox Grid.Column="0" Grid.Row="1" Margin="2" Text="{Binding Path=Customer}"> 
     <!--Template--> 
    </ComboBox> 
    <TextBox Grid.Column="0" Grid.Row="3" Margin="2" Text="{Binding Path=Contact}"></TextBox> 
    <TextBox Grid.Column="1" Grid.Row="1" Margin="2" Text="{Binding Path=PresentationDate}"></TextBox> 
    <ComboBox Grid.Column="2" Grid.Row="1" Margin="2" Text="{Binding Path=Action}"> 
     <!--Template--> 
    </ComboBox> 
    <TextBox Grid.Column="3" Grid.Row="1" Margin="2" Text="{Binding Path=InterviewDate}"></TextBox> 
    <TextBox Grid.Column="3" Grid.Row="3" Margin="2" Text="{Binding Path=InterviewTime}"></TextBox> 
    <TextBox Grid.Column="4" Grid.Row="1" Grid.RowSpan="3" Margin="2" Text="{Binding Path=Remarks}"></TextBox> 
    <StackPanel Orientation="Horizontal" Grid.Column="5" Grid.Row="1" > 
     <ComboBox Width="124" Text="{Binding Path=Manager}" Margin="2"></ComboBox> 
     <Button Width="60" Height="20" Margin="4,0,0,0" >Mail</Button> 
    </StackPanel> 
    <CheckBox Grid.Column="5" Grid.Row="3" Margin="2,2,4,2">Rejection communicated</CheckBox> 
    </Grid> 
     </DataTemplate> 
    </ListBox.ItemTemplate> 
</ListBox> 

如果我把從<DataTemplate>標記之間完全相同的代碼：

<UserControl x:Class="CandiMan.View.CandidatePresentationControl" 
    xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation" 
    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml" 
    xmlns:cm="clr-namespace:CandiMan;assembly=CandiMan" 
    xmlns:vw="clr-namespace:CandiMan.View;assembly=CandiMan" 
    xmlns:vm="clr-namespace:CandiMan.ViewModel;assembly=CandiMan"    
    Height="100" Width="880" BorderBrush="Black" BorderThickness="1"> 

    <Grid x:Name="Grid" Height="100" Width="880" Background="LightGray"> 
     <Grid.RowDefinitions> 
      <RowDefinition Height="24"/> 
      <RowDefinition Height="24"/> 
      <RowDefinition Height="24"/> 
      <RowDefinition Height="24"/> 
     </Grid.RowDefinitions> 
     <Grid.ColumnDefinitions> 
      <ColumnDefinition Width="190" /> 
      <ColumnDefinition Width="100" /> 
      <ColumnDefinition Width="100" /> 
      <ColumnDefinition Width="100" /> 
      <ColumnDefinition Width="190" /> 
      <ColumnDefinition Width="200" /> 
     </Grid.ColumnDefinitions> 
     <Label Grid.Column="0" Grid.Row="0">Client</Label> 
     <Label Grid.Column="0" Grid.Row="2">Contact</Label> 
     <Label Grid.Column="1" Grid.Row="0">Date Presentation</Label> 
     <Label Grid.Column="2" Grid.Row="0">Action</Label> 
     <Label Grid.Column="3" Grid.Row="0">Date Interview</Label> 
     <Label Grid.Column="3" Grid.Row="2">Time Interview</Label> 
     <Label Grid.Column="4" Grid.Row="0">Remarks</Label> 
     <Label Grid.Column="5" Margin="0,0,2,0">managed by</Label> 
     <ComboBox Grid.Column="0" Grid.Row="1" Margin="2" Text="{Binding Path=Customer}"> 
      <!--Template--> 
     </ComboBox> 
     <TextBox Grid.Column="0" Grid.Row="3" Margin="2" Text="{Binding Path=Contact}"></TextBox> 
     <TextBox Grid.Column="1" Grid.Row="1" Margin="2" Text="{Binding Path=PresentationDate}"></TextBox> 
     <ComboBox Grid.Column="2" Grid.Row="1" Margin="2" Text="{Binding Path=Action}"> 
      <!--Template--> 
     </ComboBox> 
     <TextBox Grid.Column="3" Grid.Row="1" Margin="2" Text="{Binding Path=InterviewDate}"></TextBox> 
     <TextBox Grid.Column="3" Grid.Row="3" Margin="2" Text="{Binding Path=InterviewTime}"></TextBox> 
     <TextBox Grid.Column="4" Grid.Row="1" Grid.RowSpan="3" Margin="2" Text="{Binding Path=Remarks}"></TextBox> 
     <StackPanel Orientation="Horizontal" Grid.Column="5" Grid.Row="1" > 
      <ComboBox Width="124" Text="{Binding Path=Manager}" Margin="2"></ComboBox> 
      <Button Width="60" Height="20" Margin="4,0,0,0" >Mail</Button> 
     </StackPanel> 
     <CheckBox Grid.Column="5" Grid.Row="3" Margin="2,2,4,2">Rejection communicated</CheckBox> 
     </Grid> 

</UserControl> 

到一個名爲CandidatePresentationControl用戶控件和不喜歡它

<ListBox> 
    <ListBox.ItemTemplate> 
     <DataTemplate> 
      <Grid> 
       <vw:CandidatePresentationControl/> 
      </Grid> 
     </DataTemplate> 
    </ListBox.ItemTemplate> 
</ListBox> 

它不會被渲染。沒有錯誤，只是一個空的列表框。有人能幫我嗎？？

謝謝！

編輯：我忘了一些東西，不知道是否重要：我正在做這件事的整個事情，也是一個用戶控件。

Answer 1

它應該沒有關係，即您引用的UserControl在另一個UserControl內。嘗試以下步驟以更好地調試您的XAML代碼：http://beacosta.com/blog/?p=52

由於您的數據在XAML中硬連接，因此解釋空ListBox的唯一方法是，您的UserControl無法通過父UserControl找到，imo 。

Answer 2

<ListBox> 
    <ListBox.ItemTemplate> 
     <DataTemplate> 
      <Grid> 
       <vw:CandidatePresentationControl DataContext="{Binding}"/> 
      </Grid> 
     </DataTemplate> 
    </ListBox.ItemTemplate> 
</ListBox> 

你必須以綁定的DataContext來寫這樣一來，我建議你看一下MVVM，會給你如何做到這一點甚至更好的辦法的想法。