Basic idea which I had was to create one button with which I will fill TreeView over XML or MySQL. Problem is that idea which I had was not so simple to implement, because probably  can not just "fill" on click tree, but I have to bind... I guess is that I would need to create class for MySQL and over Autofac to update class responsible for binding treeview. Since I need that piece of code to understand autofac better, I will write it here.

First what I did is to implement interface of all interfaces :) that means that this interface will be later used for actual implementation: 

public interface IRead
{
	List<string> Read();
}

Then I implemented IReadAndCreateTree like:

public interface IReadAndCreateTree
{
	List<string> ReadXML();
}

Then model where "all things come together":

public class XmlTreeReader : IReadAndCreateTree
{
	private IRead _reader;

	public XmlTreeReader(IRead reader)
	{
		_reader = reader;
	}

	public List<string> ReadXML()
	{
		return this._reader.Read();
	}
}

Now model which I will use for my XAML:

public class XmlTreeReader : IReadAndCreateTree
{
	private IRead _reader;

	public XmlTreeReader(IRead reader)
	{
		_reader = reader;
	}

	public List<string> ReadXML()
	{
		return this._reader.Read();
	}
}

On the end XAML:

<Window x:Class="AutofacTreeView.MainWindow"
        xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
        xmlns:viewModel="clr-namespace:AutofacTreeView.ViewModel"
        xmlns:model="clr-namespace:AutofacTreeView.Model"
        Title="MainWindow" Height="350" Width="525">
    <Grid>
        <StackPanel>
            <StackPanel.Resources>
                <viewModel:LoadXMLClick x:Key="LoadXMLClick"/>
                <model:TreeViewModel x:Key="TreeViewModel"/>
            </StackPanel.Resources>
            <TreeView x:Name="tvAutofac" DataContext="{StaticResource TreeViewModel}" ItemsSource="{Binding Path=TreeViewModels}" Height="205"/>
            <Button DataContext="{StaticResource LoadXMLClick}" Content="Load XML" Command="{Binding LoadXmlClickCommand}"/>
        </StackPanel>
    </Grid>
</Window>

I hope this is all