private static object CoerceRectInterior(DependencyObject d, object value)
{
PuncturedRect pr = (PuncturedRect)d;
Rect rcExterior = pr.RectExterior;
Rect rcProposed = (Rect)value;
double left = Math.Max(rcProposed.Left, rcExterior.Left);
double top = Math.Max(rcProposed.Top, rcExterior.Top);
double width = Math.Min(rcProposed.Right, rcExterior.Right) - left;
double height = Math.Min(rcProposed.Bottom, rcExterior.Bottom) - top;
rcProposed = new Rect(left, top, width, height);
return(rcProposed);
}
public CroppingAdorner(UIElement adornedElement, Rect rcInit)
: base(adornedElement)
{
_vc = new VisualCollection(this);
_prCropMask = new PuncturedRect();
_prCropMask.IsHitTestVisible = false;
_prCropMask.RectInterior = rcInit;
_prCropMask.Fill = Fill;
_vc.Add(_prCropMask);
_cnvThumbs = new Canvas();
_cnvThumbs.HorizontalAlignment = HorizontalAlignment.Stretch;
_cnvThumbs.VerticalAlignment = VerticalAlignment.Stretch;
_vc.Add(_cnvThumbs);
BuildCorner(ref _crtTopLeft, Cursors.SizeNWSE);
BuildCorner(ref _crtTopRight, Cursors.SizeNESW);
BuildCorner(ref _crtBottomLeft, Cursors.SizeNESW);
BuildCorner(ref _crtBottomRight, Cursors.SizeNWSE);
BuildCorner(ref _crtCentred, Cursors.SizeAll, Brushes.Tomato);
// Add handlers for Cropping.
_crtBottomLeft.DragDelta += new DragDeltaEventHandler(HandleBottomLeft);
_crtBottomRight.DragDelta += new DragDeltaEventHandler(HandleBottomRight);
_crtTopLeft.DragDelta += new DragDeltaEventHandler(HandleTopLeft);
_crtTopRight.DragDelta += new DragDeltaEventHandler(HandleTopRight);
_crtCentred.DragDelta += new DragDeltaEventHandler(HandleCentred);
// We have to keep the clipping interior withing the bounds of the adorned element
// so we have to track it's size to guarantee that...
FrameworkElement fel = adornedElement as FrameworkElement;
if (fel != null)
{
fel.SizeChanged += new SizeChangedEventHandler(AdornedElement_SizeChanged);
}
}
