private bool IsBroken(LogicalMainTrack result, LogicalMainTrack current)
{
if (result.IsEof || current.IsEof)
{
return(true);
}
if (result.IsContainer)
{
if (IsVirtualized(result.ContainerOrdinal))
{
return(true);
}
return(IsBrokenToContainer(current));
}
else if (result.IsHead)
{
return(IsBrokenToHead(current));
}
else
{
Debug.Assert(result.IsTail);
return(IsBrokenToTail(current));
}
}
private int GetPageTailContainerOrdinal(bool enforceCurrent)
{
if (ContainerViewList.Count == 0)
{
return(-1);
}
var containerOrdinal = ContainerViewList.Last.ContainerOrdinal;
var endTrack = GridTracksMain.GetGridSpan(Template.ContainerRange).EndTrack;
var endGridExtent = new LogicalMainTrack(endTrack, ContainerViewList.Last).EndGridExtent;
var isClipped = IsTailClippedMain(endGridExtent);
if (PreviousContainerAsPageTail(containerOrdinal, isClipped, enforceCurrent))
{
containerOrdinal--;
endGridExtent -= ContainerTracksCountMain;
isClipped = false;
}
if (enforceCurrent && isClipped)
{
ScrollToMain(endGridExtent - 1, 1, GridPlacement.Tail, false);
}
return(containerOrdinal);
}
private int GetPageHeadContainerOrdinal(bool enforceCurrent)
{
if (ContainerViewList.Count == 0)
{
return(-1);
}
var containerOrdinal = ContainerViewList.First.ContainerOrdinal;
var startTrack = GridTracksMain.GetGridSpan(Template.ContainerRange).StartTrack;
var startGridExtent = new LogicalMainTrack(startTrack, ContainerViewList.First).StartGridExtent;
var isClipped = IsHeadClippedMain(startGridExtent);
if (NextContainerAsPageHeader(containerOrdinal, isClipped, enforceCurrent))
{
containerOrdinal++;
startGridExtent += ContainerTracksCountMain;
isClipped = false;
}
if (enforceCurrent && isClipped)
{
ScrollToMain(startGridExtent, 0, GridPlacement.Head, false);
}
return(containerOrdinal);
}
private double GetRelativePositionMain(ContainerView containerView, GridTrack gridTrack, double fraction)
{
Debug.Assert(gridTrack.IsContainer);
Debug.Assert(fraction >= 0 && fraction <= 1);
var result = GetRelativePositionMain(containerView, gridTrack);
if (fraction > 0)
{
result += new LogicalMainTrack(gridTrack, containerView).Length *fraction;
}
return(result);
}
private bool IsBrokenToHead(LogicalMainTrack track)
{
Debug.Assert(!track.IsEof);
if (track.IsHead)
{
return(false);
}
else if (track.IsContainer)
{
return(IsFirstRowVirtualized);
}
else
{
Debug.Assert(track.IsTail);
return(ContainerViewList.Count > 0);
}
}
private bool IsBrokenToContainer(LogicalMainTrack track)
{
Debug.Assert(!track.IsEof);
if (track.IsContainer)
{
return(IsVirtualized(track.ContainerOrdinal));
}
else if (track.IsHead)
{
return(IsFirstRowVirtualized);
}
else
{
Debug.Assert(track.IsTail);
return(!IsLastRowVirtualized);
}
}
