Binding objects defined in code-behind

There's a much easier way of doing this. You can assign a Name to your Window or UserControl, and then binding by ElementName.

Window1.xaml

<Window x:Class="QuizBee.Host.Window1"
        x:Name="Window1"
        xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml">

    <ListView ItemsSource="{Binding ElementName=Window1, Path=myDictionary}" />
</Window>

Window1.xaml.cs

public partial class Window1:Window
{
    // the property must be public, and it must have a getter & setter
    public Dictionary<string, myClass> myDictionary { get; set; }

    public Window1()
    {
        // define the dictionary items in the constructor
        // do the defining BEFORE the InitializeComponent();

        myDictionary = new Dictionary<string, myClass>()
        {
            {"item 1", new myClass(1)},
            {"item 2", new myClass(2)},
            {"item 3", new myClass(3)},
            {"item 4", new myClass(4)},
            {"item 5", new myClass(5)},
        }; 

        InitializeComponent();
    }
}

You can set the DataContext for your control, form, etc. like so:

DataContext="{Binding RelativeSource={RelativeSource Self}}"

Clarification:

The data context being set to the value above should be done at whatever element "owns" the code behind -- so for a Window, you should set it in the Window declaration.

I have your example working with this code:

<Window x:Class="MyClass"
  Title="{Binding windowname}"
  DataContext="{Binding RelativeSource={RelativeSource Self}}"
  Height="470" Width="626">

The DataContext set at this level then is inherited by any element in the window (unless you explicitly change it for a child element), so after setting the DataContext for the Window you should be able to just do straight binding to CodeBehind properties from any control on the window.