private Thickness calculateThickness(ElementPresenter host)
{
var element = host.Element;
if (element == null)
{
return(new Thickness());
}
double baseThickness = host.ElementBorderWidth;
switch (element.Index)
{
case 0:
case 1:
case 3:
case 4:
return(new Thickness(0, 0, baseThickness, baseThickness));
case 2:
case 5:
return(new Thickness(0, 0, 0, baseThickness));
case 6:
case 7:
return(new Thickness(0, 0, baseThickness, 0));
default:
return(new Thickness(0));
}
}
public BorderThicknessUpdator(ElementPresenter host)
{
if (host == null)
{
throw new ArgumentNullException("host");
}
this.host = host;
DependencyPropertyDescriptor.FromProperty(
ElementPresenter.ElementBorderWidthProperty,
typeof(ElementPresenter))
.AddValueChanged(host, UpdateNeeded);
DependencyPropertyDescriptor.FromProperty(
ElementPresenter.ElementProperty,
typeof(ElementPresenter))
.AddValueChanged(host, UpdateNeeded);
}
private void updateElementBorderThickness(ElementPresenter host)
{
host.SetElementBorderThickness(calculateThickness(host));
}