AttachableForStyleBehavior

AttachableForStyleBehavior.cs

public class AttachableForStyleBehavior<TComponent, TBehavior> : Behavior<TComponent>
        where TComponent : DependencyObject
        where TBehavior : AttachableForStyleBehavior<TComponent, TBehavior>, new()
{
    public static readonly DependencyProperty IsEnabledForStyleProperty =
        DependencyProperty.RegisterAttached(
            "IsEnabledForStyle",
            typeof(bool),
            typeof(AttachableForStyleBehavior<TComponent, TBehavior>),
            new FrameworkPropertyMetadata(false, OnIsEnabledForStyleChanged));

    public bool IsEnabledForStyle
    {
        get => (bool)GetValue(IsEnabledForStyleProperty);
        set => SetValue(IsEnabledForStyleProperty, value);
    }

    private static void OnIsEnabledForStyleChanged(DependencyObject d, DependencyPropertyChangedEventArgs e)
    {
        if (d is UIElement uie)
        {
            var behColl = Interaction.GetBehaviors(uie);
            var existingBehavior = behColl.FirstOrDefault(b => b.GetType() == typeof(TBehavior)) as TBehavior;

            if ((bool)e.NewValue == false && existingBehavior is not null)
            {
                behColl.Remove(existingBehavior);
            }
            else if ((bool)e.NewValue == true && existingBehavior is null)
            {
                behColl.Add(new TBehavior());
            }
        }
    }
}