Binding data to Header for LongListSelector (toolkit)

Question

I would like to bind data to the a LongListSelector's header template. Here is the xaml code

 <toolkit:LongListSelector  x:Name="_List"  Background="Transparent" IsFlatList="True"   ItemTemplate="{StaticResource SmallImageTemplate}"
            ListHeaderTemplate="{StaticResource ListHeader}" ListFooterTemplate="{StaticResource EmptyListFooter}"  />

and in c# i have :

_List.ItemsSource = ListOfItems;

but i would like to have a different header for every scenario, so how can i bind data to the template header?

Answer 1

Use a DataTemplateSelector , and determine what template you want to use, based on the bound data.

You can also use this for the question you asked the other day.

public class DataTemplateSelector : ContentControl
{
    public virtual DataTemplate SelectTemplate(object item, DependencyObject container)
    {
        throw new NotImplementedException();
    }

    protected override void OnContentChanged(object oldContent, object newContent)
    {
        base.OnContentChanged(oldContent, newContent);

        ContentTemplate = SelectTemplate(newContent, this);
    }
}

and then a template of your choice, depending on data. Here's one of mine:

public class EventTemplateSelector : DataTemplateSelector
{
    public DataTemplate BreakTemplate
    {
        get;
        set;
    }

    public DataTemplate EventTemplate
    {
        get;
        set;
    }

    public DataTemplate DefaultTemplate
    {
        get;
        set;
    }

    public override DataTemplate SelectTemplate(object item, DependencyObject container)
    {
        if (item == null)
            return DefaultTemplate;

        // important stuff here
        var _event = item as ConferenceEvent;
        if (_event != null)
            return _event.IsBreak ? BreakTemplate : EventTemplate;
        else
            return DefaultTemplate;
    }
}