Silverlight如何在绑定到复杂集合时如何将数据模板选择器用于列表框项目

Question

I have been looking at samples of DataTemplateSelectors for sivleright and from the examples I have seen the values being returned and evaluated within the Content Control seems to be a single property that has been returned to the listbox from a collection.

Does anyone have any suggestions on how this is addressed when returning a complex collection to a listbox item source? By complex collection I mean an observable collection named "Result" and within that a List collection exists titled "Names" ? I need to trigger the data template selector from a property found within the List collection and not properties from the result collection. ie List collection may contain the properties name, sex, age and I want to use the sex property as the trigger whereas Result may contain properties like property, time, or notes and I do not need to use these to invoke the template trigger.

Thank you for any suggestions.

Update with code example

Working through this where I am getting stuck is in the binding of my listbox item custom template. Here is the listbox control xaml

<ListBox HorizontalAlignment="Stretch" ItemsSource="{Binding SearchResults[0].Results, Mode=TwoWay}" ScrollViewer.HorizontalScrollBarVisibility="Disabled" BorderBrush="#66C4C4C4" >
        <ListBox.ItemTemplate>
            <DataTemplate>
                <qr:SearchResultItemControl />
            </DataTemplate>
        </ListBox.ItemTemplate>
    </ListBox>

qr:SerarchResultItemContol xaml is the custom lsitbox item I currently have defined this user control contains the following elements

<Grid x:Name="LayoutRoot">
    <Grid.ColumnDefinitions>
        <ColumnDefinition Width="92.915"/>
        <ColumnDefinition/>
    </Grid.ColumnDefinitions>
    <Rectangle Fill="#FFF4F4F5" Margin="5,6,7.5,0" RadiusY="4" RadiusX="4" Stroke="Black" Height="52" VerticalAlignment="Top"/>
    <TextBlock Margin="4,3,76,0" TextWrapping="Wrap" FontSize="13.333" Height="17" VerticalAlignment="Top" Grid.Column="1" d:LayoutOverrides="VerticalAlignment" FontWeight="Bold" Text="{Binding Type, Mode=TwoWay}"/>
    <TextBlock Margin="8,15,10.5,0" TextWrapping="Wrap" FontSize="9.333" Height="35" VerticalAlignment="Top" d:LayoutOverrides="VerticalAlignment" Text="image placeholder" TextAlignment="Center"/>
    <TextBlock Margin="3,97,4,0" TextWrapping="Wrap" FontSize="12" Height="17" VerticalAlignment="Top" Text="{Binding Relevance, Mode=TwoWay}"/>
    <TextBlock Margin="3,75,20,0" TextWrapping="Wrap" FontSize="12" Height="18" VerticalAlignment="Top" Width="70" Text="{StaticResource txtRelevance}"/>
    <TextBlock Grid.Column="1" Margin="4,24,5,6" TextWrapping="Wrap" FontSize="12" RenderTransformOrigin="0.5,0.5" Text="{Binding HitContext, Mode=TwoWay}"/>
</Grid>

Running this the control works fine I see my results. What I would like to do is control what data ListboxItem template is loaded based upon the value returned in Type binding.

The itemsSource is being returned from my view model SearchResults Collection which is being generated from a WcF service.

VM code for bindable collection:

public ObservableCollection<QueryResponse> SearchResults
    {
        get
        {
            return this._SearchResults;
        }
        private set
        {
            if (this._SearchResults == value)
                return;

            // Set the new value and notify
            this._SearchResults = value;
            this.NotifyPropertyChanged("SearchResults");//this binds to UI search returns
        }
    }

the searchresult collection is comprised of the following properties

SearchResult string QueryText string QueryTime Results string TotalMatches ...

The Results collection that is returned within SearchResult contains: string Content string HitContext string ID string relevance string Type

What I am trying to accomplish is to have the DataTemplateSelection triggered off of the Type value returned from the results collection.

Any suggestions would be appreciated.

Answer 1

Found my answer based upon the following solution from codeproject This solution provided a very basic and straight forward DataSelection template that fit my needs.

With regards to accessing a complex collection vs. a flat collection I cast my item object against the nested collection and from there able to access the appropriate properties.