How to work on a view control from viewmodel

Hello !

I'm trying to integrate a news ticker in my WPF project. I'm working on this one (http://www.jarloo.com/rumormill4), to work with Mvvm light without caliburn micro.I have three elements :

-Ticker Windows (the main windows) - TickerWindow

-Ticker Layout (userview for buttons) - TickerLayout

-Ticker Item (for the animated text which takes places in a canvas on ticker layout view ) - TickerNormalView

Ticker Windows (this on show up after a timer tick event)

<Window x:Class="TerminalClient_Mvvmlight.Views.Ticker.TickerWindow"
        xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
        xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
        xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
        xmlns:ignore="http://www.ignore.com"
        xmlns:Views="clr-namespace:TerminalClient_Mvvmlight.Views.Ticker"
        xmlns:vm="clr-namespace:TerminalClient_Mvvmlight.ViewModel"
        xmlns:i="http://schemas.microsoft.com/expression/2010/interactivity"
        xmlns:command="http://www.galasoft.ch/mvvmlight"
        mc:Ignorable="d ignore"
        WindowStyle="None" Height="44.949" Width="931.35"
        DataContext="{Binding TickerWindowsVM, Source={StaticResource Locator}}"><i:Interaction.Triggers><i:EventTrigger EventName="Loaded"><command:EventToCommand Command="{Binding FirstViewCommand}"/></i:EventTrigger></i:Interaction.Triggers><Grid><ContentControl Content="{Binding CurrentViewModel}" /></Grid></Window>

My ContentControl load my TickerLayout view

<UserControl x:Class="TerminalClient_Mvvmlight.Views.Ticker.TickerLayout"
        xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
        xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
        xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
        xmlns:tb="http://www.hardcodet.net/taskbar"
        xmlns:i="http://schemas.microsoft.com/expression/2010/interactivity"
        xmlns:command="http://www.galasoft.ch/mvvmlight"
        xmlns:ignore="http://www.ignore.com"
        xmlns:Views="clr-namespace:TerminalClient_Mvvmlight.Views.Ticker"
        mc:Ignorable="d ignore"
        Height="38"
        Width="900"
        DataContext="{Binding TickerLayoutVM, Source={StaticResource Locator}}"><Canvas x:Name="LayoutRoot"><Button Content="X" Canvas.Left="873" Canvas.Top="10" Width="17"/></Canvas></UserControl>

And my problem is here... I'm trying to found a solution to access to the canvas "LayoutRoot" for instanciate my Ticker in it.

My TickerLayoutViewModel

 public class TickerLayoutViewModel : ViewModelBase
    {
        private Ticker<TickerNormalView> ticker;
        private readonly FeedManager manager = new FeedManager();

        public ICommand TickerLoadCommand { get; private set; }

        public TickerLayoutViewModel()
        {
            //CurrentViewModel = TickerViewModel._firstViewModel;
            manager.NewFeedItem += (o, e) => Execute.BeginOnUIThread(() => AddItem(e.Item));
            TickerLoadCommand = new RelayCommand(() => LoadTicker());
        }

        private void AddItem(FeedItem itm)
        {
            ticker.Items.Enqueue(new TickerNormalView(itm));
        }

        private void LoadTicker()
        {
            MessageBox.Show("TickerLayout load !");
            ticker = new Ticker<TickerNormalView>(new TickerLayout().LayoutRoot);
            ticker.Speed = new TimeSpan(0, 1, 0);
            manager.Start();
            ticker.Start();
        }
    }

I'm searching how to synchronise this code line :

ticker = new Ticker<TickerNormalView>(new TickerLayout().LayoutRoot);

With the instance of my TickerLayout view opened in my window.

I'm very lost... so could you give an example ? or a better solution ?

Thanks for any help