Q:

Unity Container resolving with UnityDependencyResolver

I'm using dependency injection with Microsoft Unity.  But I'm having problems when I have to Resolve the instances. 
My scenario: I have a WPF application and a class library.  Unity is installed in the class library. 
I'm trying to create an object using the dependency injection. 
I got the following error:

The type 'Microsoft. Practices. Unity. IUnityContainer' is defined in an assembly that is not referenced.  You must add a reference to assembly 'Microsoft. Practices. Unity, Version=4.0.0.0, Culture=neutral, PublicKeyToken=6d32ff45e0ccc69f'. 

Code:
UnityDependencyResolver ObjUnityDependencyResolver = new UnityDependencyResolver(UnityContainerConfig. Initialize());
var myclass = ObjUnityDependencyResolver. GetService(typeof(IMyClass));
myclass. HelloWorld(); //Console. Write("Hello World");

This is my unity container:
public static class UnityContainerConfig
{
    private static IUnityContainer _unityContainer = null;

    public static IUnityContainer Initialize()
    {
        if (_unityContainer == null)
        {
            _unityContainer = new Microsoft. Practices. Unity. UnityContainer()
            .RegisterType<IMyClass, MyClass>();
        }

        return _unityContainer;
    }
}

This is my unity resolver:
public class UnityDependencyResolver : IDependencyResolver
{
    private IUnityContainer _unityContainer = null;

    public UnityDependencyResolver(IUnityContainer unityContainer)
    {
        this._unityContainer = unityContainer;
    }

    public object GetService(Type serviceType)
    {
        try
        {
            return _unityContainer. Resolve(serviceType);
        }
        catch
        {
            return null;
        }
    }

    public IEnumerable<object> GetServices(Type serviceType)
    {
        try
        {
            return _unityContainer. ResolveAll(serviceType);
        }
        catch
        {
            return new List<object>();
        }
    }
}

I have to install the Unity in every single project in my solution? 
What's the "better way to create an instance" and use the dependency injection by unity? 

A:

You only need to install Unity in the client project,  and don't use _unityContainer. Resolve(serviceType), if you configure your project carefully, Unity will take care of resolving every service, 

