MainWindow.xaml

<Window
    xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
    x:Class="SO8WPF.MainWindow"
    Title="Test" Height="150" Width="350">
    <Grid>
        <ItemsControl ItemsSource="{Binding}">
            <ItemsControl.ItemsPanel>
                <ItemsPanelTemplate>
                    <UniformGrid IsItemsHost="True" Rows="2" Columns="3"/>
                </ItemsPanelTemplate>
            </ItemsControl.ItemsPanel>
            <ItemsControl.ItemTemplate>
                <DataTemplate>
                    <Button>
                        <Button.Template>
                            <ControlTemplate>
                                <Image Source="{Binding Path=Uri}" />
                            </ControlTemplate>
                        </Button.Template>
                    </Button>
                </DataTemplate>
            </ItemsControl.ItemTemplate>
        </ItemsControl>
    </Grid>
</Window>