/// <summary>
/// RibbonToolTip custom placement logic
/// </summary>
/// <param name="popupSize">The size of the popup.</param>
/// <param name="targetSize">The size of the placement target.</param>
/// <param name="offset">The Point computed from the HorizontalOffset and VerticalOffset property values.</param>
/// <returns>An array of possible tooltip placements.</returns>
private CustomPopupPlacement[] PlaceRibbonToolTip(Size popupSize, Size targetSize, Point offset)
{
UIElement placementTarget = this.PlacementTarget;
double belowOffsetY = 0.0;
double aboveOffsetY = 0.0;
double offsetX = FlowDirection == FlowDirection.LeftToRight ? 0.0 : -popupSize.Width;
if (IsPlacementTargetInRibbonGroup)
{
// If the PlacementTarget is within a RibbonGroup we proceed
// with the custom placement policy.
// Walk up the visual tree from PlacementTarget to find the Ribbon
// if exists or the root element which is likely a PopupRoot.
Ribbon ribbon = null;
DependencyObject rootElement = null;
DependencyObject element = placementTarget;
while (element != null)
{
ribbon = element as Ribbon;
if (ribbon != null)
{
break;
}
rootElement = element;
element = VisualTreeHelper.GetParent(element);
}
double additionalOffset = 1.0;
FrameworkElement referenceFE = null;
if (ribbon != null)
{
additionalOffset = 0.0;
referenceFE = ribbon;
}
else
{
if (rootElement != null)
{
referenceFE = rootElement as FrameworkElement;
}
}
if (referenceFE != null)
{
// When RibbonControl (PlacementTarget) is within a collapsed group RibbonToolTip is
// placed just below the Popup or just above the Popup (in case there is not enough
// screen space left below the Popup).
MatrixTransform transform = referenceFE.TransformToDescendant(placementTarget) as MatrixTransform;
if (transform != null)
{
MatrixTransform deviceTransform = new MatrixTransform(RibbonHelper.GetTransformToDevice(referenceFE));
GeneralTransformGroup transformGroup = new GeneralTransformGroup();
transformGroup.Children.Add(transform);
transformGroup.Children.Add(deviceTransform);
Point leftTop, rightBottom;
transformGroup.TryTransform(new Point(0, 0), out leftTop);
transformGroup.TryTransform(new Point(referenceFE.ActualWidth, referenceFE.ActualHeight), out rightBottom);
belowOffsetY = rightBottom.Y + additionalOffset;
aboveOffsetY = leftTop.Y - popupSize.Height - additionalOffset;
}
}
}
else
{
// If PlacementTarget isn't within a RibbonGroup we shouldn't have
// gotten here in the first place. But now that we are we will make
// the best attempt at emulating PlacementMode.Bottom.
FrameworkElement placementTargetAsFE = placementTarget as FrameworkElement;
if (placementTargetAsFE != null)
{
belowOffsetY = targetSize.Height;
aboveOffsetY = -popupSize.Height;
}
}
// This is the prefered placement, below the ribbon for controls within Ribbon or below the Popup for controls within Popup.
CustomPopupPlacement placementPreffered = new CustomPopupPlacement(new Point(offsetX, belowOffsetY), PopupPrimaryAxis.Horizontal);
// This is a fallback placement, if the tooltip will not fit below the ribbon or Popup, place it above the ribbon or Popup.
CustomPopupPlacement placementFallback = new CustomPopupPlacement(new Point(offsetX, aboveOffsetY), PopupPrimaryAxis.Horizontal);
return(new CustomPopupPlacement[] { placementPreffered, placementFallback });
}