private static void OnImagePickerSelectActionChanged(DependencyObject depobj, DependencyPropertyChangedEventArgs evargs)
        {
            ImagePickerSimple tb = depobj as ImagePickerSimple;

            tb.ImagePickerSelectAction = (Action <string, object, object>)evargs.NewValue;
        }
        private static void OnImagePickerActionFieldSourceChanged(DependencyObject depobj, DependencyPropertyChangedEventArgs evargs)
        {
            ImagePickerSimple tb = depobj as ImagePickerSimple;

            tb.ImagePickerActionFieldSource = evargs.NewValue;
        }