Once you appropriate the ItemsSource with the correct value XAML doesn't automatically reilitialize the gathering of things. So your DataContext for "video_length_textbox" is set to alone, as well as your IncrementingTextBox class doesn't have a public property identified as ConfigurationModel And the trouble the binding is having would be that https://furnishedlofficeinnoida.blogspot.com/2025/05/shape-your-future-on-solid-ground-with.html