private static Point CalculateLocation(AdornerLocation anchor, Size adorneeSize, Size adornerSize)
{
Point location = new Point();
switch (anchor)
{
case AdornerLocation.BottomRight:
location = new Point(adorneeSize.Width, 0);
break;
case AdornerLocation.TopRight:
location = new Point(adorneeSize.Width, -adornerSize.Height);
break;
case AdornerLocation.TopLeft:
location = new Point(adorneeSize.Width - adornerSize.Width, -adornerSize.Height);
break;
case AdornerLocation.BottomLeft:
location = new Point(adorneeSize.Width - adornerSize.Width, 20);
break;
}
return(location);
}
protected override Size ArrangeOverride(Size finalSize)
{
Point anchorPoint = this.AdornedElement.TranslatePoint(new Point(this.AdornedElement.RenderSize.Width, 0), this.ScrollViewer);
AdornerLocation anchor = AnnotationAdorner.GetAnchor(this);
if (anchor == AdornerLocation.None)
{
// Calculate based on the real size of the adorner, depending on current zoom level
DesignerView designerView = ((WorkflowViewElement)AdornedElement).Context.Services.GetService <DesignerView>();
double zoomLevel = designerView.ZoomFactor;
Size adornerSize = new Size(this.content.DesiredSize.Width * zoomLevel, this.content.DesiredSize.Height * zoomLevel);
anchor = FindAnchor(anchorPoint, adornerSize, new Rect(0, 0, this.ScrollViewer.ViewportWidth, this.ScrollViewer.ViewportHeight));
AnnotationAdorner.SetAnchor(this, anchor);
}
Point location = CalculateLocation(anchor, this.AdornedElement.RenderSize, this.content.DesiredSize);
this.content.Arrange(new Rect(location, finalSize));
return(finalSize);
}
// (3) | (2)
// ______|______
// (4) | (1)
// |
// canvas is divided into four areas by anchorPoint
// try to figure out which area could fit desiredSize from area1 to area4, if there's no fit, default to area4.
internal static AdornerLocation FindAnchor(Point anchorPoint, Size desiredSize, Rect canvas)
{
Fx.Assert(anchorPoint.X >= canvas.X && anchorPoint.X <= canvas.X + canvas.Width, "X axis of anchorPoint not within canvas");
Fx.Assert(anchorPoint.Y >= canvas.Y && anchorPoint.Y <= canvas.Y + canvas.Height, "Y axis of anchorPoint not within canvas");
AdornerLocation anchor = AdornerLocation.None;
// try area 1 and 2
if (anchorPoint.X + desiredSize.Width <= canvas.X + canvas.Width)
{
// area 1
if (anchorPoint.Y + desiredSize.Height <= canvas.Y + canvas.Height)
{
anchor = AdornerLocation.BottomRight;
}
// area 2
if (anchor == AdornerLocation.None && anchorPoint.Y - desiredSize.Height >= canvas.Y)
{
anchor = AdornerLocation.TopRight;
}
}
// area 3
if (anchor == AdornerLocation.None && anchorPoint.X - desiredSize.Width >= canvas.X && anchorPoint.Y - desiredSize.Height >= canvas.Y)
{
anchor = AdornerLocation.TopLeft;
}
// default to area 4
if (anchor == AdornerLocation.None)
{
anchor = AdornerLocation.BottomLeft;
}
return(anchor);
}
public static void SetAnchor(DependencyObject obj, AdornerLocation anchor)
{
obj.SetValue(AnnotationAdorner.AnchorProperty, anchor);
}
public static void SetAnchor(DependencyObject obj, AdornerLocation anchor)
{
obj.SetValue(AnnotationAdorner.AnchorProperty, anchor);
}
private static Point CalculateLocation(AdornerLocation anchor, Size adorneeSize, Size adornerSize)
{
Point location = new Point();
switch (anchor)
{
case AdornerLocation.BottomRight:
location = new Point(adorneeSize.Width, 0);
break;
case AdornerLocation.TopRight:
location = new Point(adorneeSize.Width, -adornerSize.Height);
break;
case AdornerLocation.TopLeft:
location = new Point(adorneeSize.Width - adornerSize.Width, -adornerSize.Height);
break;
case AdornerLocation.BottomLeft:
location = new Point(adorneeSize.Width - adornerSize.Width, 20);
break;
}
return location;
}