public SelectedItemsAdorner(UIElement adornedElement)
: base(adornedElement)
{
_canvas = new SelfCenteredCanvas()
{
Opacity = 0.3,
Visibility = System.Windows.Visibility.Visible,
Background = Brushes.Transparent,
HorizontalAlignment = HorizontalAlignment.Stretch,
VerticalAlignment = VerticalAlignment.Stretch,
};
this.AddLogicalChild(_canvas);
this.AddVisualChild(_canvas);
IsHitTestVisible = false;
}
private static void OnItemsChanged(DependencyObject d, DependencyPropertyChangedEventArgs e)
{
var adorner = d as SelectedItemsAdorner;
Point initialPosition = adorner.CurrentPosition;
var draggables = adorner.Items
.OfType <IDraggable>()
.Where(pa => pa is IPositionAware)
.Where(ipa => ipa.IsDragging).ToArray();
adorner._canvas.Children.Clear();
foreach (var item in draggables.Cast <IPositionAware>())
{
Vector offset = item.GetMiddlePoint() - initialPosition;
ContentPresenter cc = new ContentPresenter()
{
Content = item
};
SelfCenteredCanvas.SetOffsetX(cc, offset.X);
SelfCenteredCanvas.SetOffsetY(cc, offset.Y);
adorner._canvas.Children.Add(cc);
}
}
