public static void LogActiveDocument (bool transient)
{
if (switching)
return;
NavigationPoint point = GetNavPointForActiveDoc ();
if (point == null)
return;
NavigationHistoryItem item = new NavigationHistoryItem (point);
//if the current node's transient but has been around for a while, consider making it permanent
if (Current == null ||
(currentIsTransient && DateTime.Now.Subtract (Current.Created).TotalMilliseconds > TRANSIENT_TIMEOUT))
{
currentIsTransient = false;
}
//if the current point's transient, always replace it
if (currentIsTransient)
{
//collapse down possible extra point in history
NavigationHistoryItem backOne = history[-1];
if (backOne != null && point.ShouldReplace (backOne.NavigationPoint)) {
// The new node is the same as the last permanent, so we can discard it
history.RemoveCurrent ();
currentIsTransient = false;
item.Dispose ();
} else {
currentIsTransient = transient;
history.ReplaceCurrent (item);
}
}
//if the new point wants to replace the old one, let it
else if (Current != null && !transient && point.ShouldReplace (Current.NavigationPoint))
{
history.ReplaceCurrent (item);
//but in this case, the point should not be transient -- unless the old point was,
//but that's handled earlier
currentIsTransient = false;
}
//final choice: append the the node
//BUT only if the existing current node would not want to replace the new node
else if (Current == null || !Current.NavigationPoint.ShouldReplace (point))
{
history.AddPoint (item);
currentIsTransient = transient;
}
else
point.Dispose ();
OnHistoryChanged ();
}
public void Dispose()
{
navPoint.Dispose();
}
