DependencyProperty in UserControl doesn't get updated from binding - wpf

Question

Here is the reproduction of my problem:
Create a WPF Application
Add a new UserControl to the project
Replace its content with the following
<UserControl
x:Class="UserControl1"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
DataContext="{Binding RelativeSource={RelativeSource Self}}">
<TextBlock Text="{Binding MyText}"/>
</UserControl>
Public Class UserControl1
Public Property MyText As String
Get
Return GetValue(MyTextProperty)
End Get
Set(ByVal value As String)
SetValue(MyTextProperty, value)
End Set
End Property
Public Shared ReadOnly MyTextProperty As DependencyProperty =
DependencyProperty.Register("MyText", GetType(String), GetType(UserControl1))
End Class
Replace the following in the MainWindow.xaml file:
<Window
x:Class="MainWindow"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
xmlns:src="clr-namespace:WpfApplication1"
Title="MainWindow"
DataContext="{Binding RelativeSource={RelativeSource Self}}">
<StackPanel >
<TextBox Text="{Binding Title, UpdateSourceTrigger=PropertyChanged}"/>
<src:UserControl1 MyText="{Binding Title}"/>
</StackPanel>
</Window>
As you can see, the UserControl1.MyText property doesn't get updated when the MainWindow.Title changes.
What am I missing? I want the user control to be connected to the parent property, is there a xamly way to do it?

Answer 1

Okay, when I recreate the app (I'm using C#, so I don't think this will make any difference), I notice in my output the binding is failing because UserControl does not have a Title property.
Add ElementName=this to your UserControl1 binding. And set the Name property on the Window to this and that should fix it.
Something like this:
<src:UserControl1 MyText="{Binding Title, ElementName=this}" />
The binding works for me when I do that. Hope that helps!