Adding Usercontrol within another usercontrol to occupy the whole space

Question

Hello,

My usercontrol that i add programmatically doesn't show up.

This is my MainPage.xaml :-

<UserControl x:Class="ScrollingEffect.MainPage"
    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"
    mc:Ignorable="d"
    d:DesignHeight="300" d:DesignWidth="400">

    <Canvas x:Name="LayoutRoot" Background="White">
        <Canvas x:Name="content" Height="Auto" Width="Auto"/>
        <Canvas Width="Auto">
            <StackPanel Height="27" Width="1400" Background="#B2000000"/>
        </Canvas>
    </Canvas>
</UserControl>

This is my MainPage.xaml.cs :-

using System;
using System.Collections.Generic;
using System.Linq;
using System.Net;
using System.Windows;
using System.Windows.Controls;
using System.Windows.Documents;
using System.Windows.Input;
using System.Windows.Media;
using System.Windows.Media.Animation;
using System.Windows.Shapes;

namespace ScrollingEffect
{
    public partial class MainPage : UserControl
    {
        public MainPage()
        {
            InitializeComponent();
            this.Loaded += new RoutedEventHandler(MainPage_Loaded);
        }

        void MainPage_Loaded(object sender, RoutedEventArgs e)
        {
            RedBack objRedBack = new RedBack();

            content.Children.Add(objRedBack);
        }
    }
}

This is my RedBack.xaml :-

<UserControl
    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"
    mc:Ignorable="d" Margin="0" HorizontalAlignment="Stretch" VerticalAlignment="Stretch"
    x:Class="ScrollingEffect.RedBack"
    d:DesignWidth="640" d:DesignHeight="480">

    <Canvas x:Name="LayoutRoot">
        <Canvas.Background>
            <LinearGradientBrush EndPoint="0.5,1" StartPoint="0.5,0">
                <GradientStop Color="Black" Offset="0.078"/>
                <GradientStop Color="Red" Offset="1"/>
            </LinearGradientBrush>
        </Canvas.Background>
    </Canvas>
</UserControl>