private dfMarkupTag hitTestTag(dfMouseEventArgs args)
{
var relativeMousePosition = this.GetHitPosition(args) + scrollPosition;
var hitBox = viewportBox.HitTest(relativeMousePosition);
if (hitBox != null)
{
var tag = hitBox.Element;
while (tag != null && !(tag is dfMarkupTag))
{
tag = tag.Parent;
}
return(tag as dfMarkupTag);
}
return(null);
}