Can Not Bin to Dependency Property in Custom Control

[Marc Jeeves]

Within my View Model i have a property and backer to bind to the ControlHideShow, I don't get a bind error but if I change the default value in the View Model nothing happens.  If I don't bind in the Implementation XAML and set Visible or Hidden it works so why can I not bind to the ViewModel thanks Madaxe

Public interface ViewModel
{
        Visibility ControlHideShow { get; set; }
}
    
public class MainPageViewModel : ViewModelBase, IMainPageViewModel
{
    
        private Visibility _controlHideShow = Visibility.Visible;
        public Visibility ControlHideShow
        {
            get => _controlHideShow;
            set{ _controlHideShow = value;  OnPropertyChanged(nameof(ControlHideShow)); }
        }
}

Implementation XML

ControlHideShow="{Binding ControlHideShow}"/>

Custom Control XAML

[Richard Deeming]

I suspect it's because you've set the DataContext on the <UserControl> element. That means the <controls:WaitTickerControl ... ControlHideShow="{Binding ControlHideShow}" /> is binding the user control's property to itself, rather than the property from the inherited viewmodel. Try removing the DataContext assignment - you've specified the ElementName in your binding, so you shouldn't need it.

    ...

If that doesn't work, try setting the DataContext on the Grid instead of the UserControl.

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"These people looked deep within my soul and assigned me a number based on the order in which I joined." - Homer

[Marc Jeeves]

Spot on, sometimes its the wood for the trees. thanks a bunch Madaxe