Unlike WPF, Silverlight doesn't contain a DataTemplateSelector. A DataTemplateSelector is used to select a data template based on the data-bound element and the data object. But, it isn't hard to build your own.
Start by adding a class to the solution and call it something like “DataTemplateSelector”. Inherit this class from System.Windows.Controls.ContentControl. The ContentControl class has a property for a data template and a property for content, which you can use to data-bind to. Next, create an override on the OnContentChanged method like this:
protected override void OnContentChanged(object oldContent, object newContent)
{
}
In the OnContentChanged method, set the template of the to a template picked from the dictionary. Add something like the code below to method:
if (((int)newContent % 2) == 0)
{
ContentTemplate = DataTemplateHelper.LoadFromDictionary(
"DataTemplateDemo;component/DataTemplates.xaml",
"EvenDataTemplate");
}
else
{
ContentTemplate = DataTemplateHelper.LoadFromDictionary(
"DataTemplateDemo;component/DataTemplates.xaml",
"OddDataTemplate");
}
Personally, I prefer to place templates in a separate dictionary, just in case I need to share them between xaml files or to keep the other xaml files clean. I use a custom helper class to make this a bit easier. I’ll explain this in a bit.
In your xaml file, use the template selector class as the template of the list:
<ListBox x:Name="ListofNumbers">
<ListBox.ItemTemplate>
<DataTemplate>
<DataTemplateDemo:DataTemplateSelector
Content="{Binding}"/>
</DataTemplate>
</ListBox.ItemTemplate>
</ListBox>
I use this helper method like below to retrieve templates from dictionaries. To use the code, add a reference too System.Xml.Linq.
public static DataTemplate LoadFromDictionary(string dictionary,
string template)
{
var doc = XDocument.Load(dictionary);
var dict = (ResourceDictionary)XamlReader
.Load(doc.ToString(SaveOptions.None));
return dict[template] as DataTemplate;
}
A demo project can be downloaded here.