There is a custom control

     <ctrls:SearchDefalut Source="{Binding SearchResults}"
                          Height="40" Width="180"/>

I have a dependent property called Source

       public IEnumerable Source
       {
           get { return (IEnumerable)GetValue(SourceProperty); }
           set { SetValue(SourceProperty, value); }
       }

       // Using a DependencyProperty as the backing store for MyProperty.  This enables animation, styling, binding, etc...
       public static readonly DependencyProperty SourceProperty =
           DependencyProperty.Register("Source", typeof(IEnumerable), typeof(SearchDefalut), new PropertyMetadata(null,OnMySourcePropertyChanged));

       private static void OnMySourcePropertyChanged(DependencyObject d, DependencyPropertyChangedEventArgs e)
       {
         //TODO
       }

When I use the command to trigger the SearchResults add or remove data dependency property OnMySourcePropertyChanged Source will not be call it makes me feel very confused

     <ctrls:SearchDefalut Source="{Binding SearchResults,Mode=TwoWay}"
                          Height="40" Width="180"/>

<ctrls:SearchDefalut Source="{Binding SearchResults,Mode=OneWaySource}"
                          Height="40" Width="180"/>

So I tried to change the Mode but it still didn’t work