/// <summary>
/// Enqueues a popup at the next position within the queue.
/// </summary>
/// <param name="popup">The popup to enqueue.</param>
public void Enqueue(Popup popup)
{
Contract.Require(popup, "popup");
if (next == null)
{
queue.AddLast(popup);
}
else
{
queue.AddBefore(next, popup);
}
}
/// <summary>
/// Performs a hit test against the contents of the queue.
/// </summary>
/// <param name="point">A point in device-independent screen space to test against the contents of the queue.</param>
/// <param name="popup">The popup that contains the resulting visual.</param>
/// <returns>The topmost <see cref="Visual"/> that contains the specified point,
/// or <c>null</c> if none of the items in the queue contain the point.</returns>
public Visual HitTest(Point2D point, out Popup popup)
{
if (queue.Count == 0)
{
popup = null;
return null;
}
for (var current = queue.Last; current != null; current = current.Previous)
{
if (current.Value.IsHitTestVisible)
{
var match = current.Value.PopupHitTest(point);
if (match != null)
{
popup = current.Value;
return match;
}
}
}
popup = null;
return null;
}
/// <summary>
/// Gets a value indicating whether the queue is currently drawing the specified popup.
/// </summary>
/// <param name="popup">The popup to evaluate.</param>
/// <returns><c>true</c> if the queue is currently drawing the specified popup; otherwise, <c>false</c>.</returns>
public Boolean IsDrawingPopup(Popup popup)
{
return position != null && position.Value == popup;
}