BuildProcess/WpfControlLibrary/IpAddress/FocusChangeExtension.cs

using System.Windows;

namespace WpfControlLibrary.IpAddress
{
    public static class FocusChangeExtension
    {
        public static bool GetIsFocused(DependencyObject obj)
        {
            return ( bool ) obj.GetValue(IsFocusedProperty);
        }

        public static void SetIsFocused(DependencyObject obj, bool value)
        {
            obj.SetValue(IsFocusedProperty, value);
        }

        public static readonly DependencyProperty IsFocusedProperty =
            DependencyProperty.RegisterAttached(
                "IsFocused", typeof(bool), typeof(FocusChangeExtension),
                new UIPropertyMetadata(false, OnIsFocusedPropertyChanged));

        private static void OnIsFocusedPropertyChanged(
            DependencyObject d,
            DependencyPropertyChangedEventArgs e)
        {
            var control = (UIElement)d;
            if ( ( bool ) e.NewValue )
            {
                control.Focus();
            }
        }
    }
}