Can I make a custom gridviewitem independent of my collectionviewsource? - xaml

Question

I have a CollectionViewSource that I use to populate my gridviewitems (black squares) and I was wondering if it would be possible to add a gridviewitem (red square) independent of my collectionviewsource. I can provide any additional info needed. Thank you for the help!
I don't have enought rep to post an image so here's a link to the image showing what I want to do:
Image
Edit - I'm doing this in the WinRT for Windows 8

Answer 1

Yoyu can use CompositeCollection to do this sort of thing
Here is a quick example of using a CompositeCollection
Xaml:
<Window x:Class="WpfApplication10.MainWindow"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
Title="MainWindow" Height="325" Width="422" Name="UI">
<Window.Resources>
<CollectionViewSource x:Key="myViewSource" Source="{Binding Items, ElementName=UI}" />
</Window.Resources>
<Grid DataContext="{Binding ElementName=UI}">
<ListView>
<ListView.ItemsSource>
<CompositeCollection>
<ListViewItem Content="Hello" />
<CollectionContainer Collection="{Binding Source={StaticResource myViewSource}}" />
</CompositeCollection>
</ListView.ItemsSource>
</ListView>
</Grid>
</Window>
Code:
public partial class MainWindow : Window
{
public MainWindow()
{
InitializeComponent();
}
public IEnumerable<string> Items
{
get
{
yield return "Item1";
yield return "Item2";
yield return "Item3";
}
}
}
Result: