Just follow these steps; first step in creating the class to be associated with 'UserControl:
{
public CollectionUCPage ()
This creates the ' we want to inherit from the UserControl class CollectionUCPage;
file. xaml should be amended as follows:
< src : CollectionUCPage
xmlns ="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns : x ="http://schemas.microsoft.com/winfx/2006/xaml"mc : Ignorable ="d"
xmlns : src ="clr-namespace:WpfControlLibrary"
x : Name = "userme "
...
As you can see it is introduced REFERENCE or xmlns: src = "clr-namespace: WpfControlLibrary"
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