/V4/Quickstarts/BasicMVVM/BasicMVVMApp/App.xaml

<Application xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"

             xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml" 

             x:Class="BasicMVVMApp.App"

             >

    <Application.Resources>

        <ResourceDictionary>

            <ResourceDictionary.MergedDictionaries>

                <ResourceDictionary Source="Theme/Theme.xaml"/>

            </ResourceDictionary.MergedDictionaries>

        </ResourceDictionary>

    </Application.Resources>

</Application>