public virtual MarginsCollapseInfo StartChildMarginsHandling(IRenderer child, Rectangle layoutBox)
{
if (backupLayoutBox != null)
{
// this should happen only if previous kid was floated
RestoreLayoutBoxAfterFailedLayoutAttempt(layoutBox);
RemoveRendererChild(--processedChildrenNum);
childMarginInfo = null;
}
rendererChildren.Add(child);
int childIndex = processedChildrenNum++;
// If renderer is floated, prepare layout box as if it was inline,
// however it will be restored from backup when next kid processing will start.
bool childIsBlockElement = !RendererIsFloated(child) && IsBlockElement(child);
backupLayoutBox = layoutBox.Clone();
backupCollapseInfo = new MarginsCollapseInfo();
collapseInfo.CopyTo(backupCollapseInfo);
PrepareBoxForLayoutAttempt(layoutBox, childIndex, childIsBlockElement);
if (childIsBlockElement)
{
childMarginInfo = CreateMarginsInfoForBlockChild(childIndex);
}
return(this.childMarginInfo);
}
public MarginsCollapseHandler(IRenderer renderer, MarginsCollapseInfo marginsCollapseInfo)
{
// Layout box and collapse info are saved before processing the next kid, in order to be able to restore it in case
// the next kid is not placed. These values are not null only between startChildMarginsHandling and endChildMarginsHandling calls.
this.renderer = renderer;
this.collapseInfo = marginsCollapseInfo != null ? marginsCollapseInfo : new MarginsCollapseInfo();
}
private void RestoreLayoutBoxAfterFailedLayoutAttempt(Rectangle layoutBox)
{
layoutBox.SetX(backupLayoutBox.GetX()).SetY(backupLayoutBox.GetY()).SetWidth(backupLayoutBox.GetWidth()).SetHeight
(backupLayoutBox.GetHeight());
backupCollapseInfo.CopyTo(collapseInfo);
backupLayoutBox = null;
backupCollapseInfo = null;
}
/// <summary>This method shall be called after child occupied area is included into parent occupied area.</summary>
public virtual void EndChildMarginsHandling(Rectangle layoutBox)
{
int childIndex = processedChildrenNum - 1;
if (RendererIsFloated(GetRendererChild(childIndex)))
{
return;
}
if (childMarginInfo != null)
{
if (firstNotEmptyKidIndex == childIndex && childMarginInfo.IsSelfCollapsing())
{
firstNotEmptyKidIndex = childIndex + 1;
}
collapseInfo.SetSelfCollapsing(collapseInfo.IsSelfCollapsing() && childMarginInfo.IsSelfCollapsing());
lastKidCollapsedAfterHasClearanceApplied = childMarginInfo.IsSelfCollapsing() && childMarginInfo.IsClearanceApplied
();
}
else
{
lastKidCollapsedAfterHasClearanceApplied = false;
collapseInfo.SetSelfCollapsing(false);
}
if (prevChildMarginInfo != null)
{
FixPrevChildOccupiedArea(childIndex);
UpdateCollapseBeforeIfPrevKidIsFirstAndSelfCollapsed(prevChildMarginInfo.GetOwnCollapseAfter());
}
if (firstNotEmptyKidIndex == childIndex && FirstChildMarginAdjoinedToParent(renderer))
{
if (!collapseInfo.IsSelfCollapsing())
{
GetRidOfCollapseArtifactsAtopOccupiedArea();
if (childMarginInfo != null)
{
ProcessUsedChildBufferSpaceOnTop(layoutBox);
}
}
}
prevChildMarginInfo = childMarginInfo;
childMarginInfo = null;
backupLayoutBox = null;
backupCollapseInfo = null;
}
private MarginsCollapseInfo CreateMarginsInfoForBlockChild(int childIndex)
{
bool ignoreChildTopMargin = false;
// always assume that current child might be the last on this area
bool ignoreChildBottomMargin = LastChildMarginAdjoinedToParent(renderer);
if (childIndex == firstNotEmptyKidIndex)
{
ignoreChildTopMargin = FirstChildMarginAdjoinedToParent(renderer);
}
MarginsCollapse childCollapseBefore;
if (childIndex == 0)
{
MarginsCollapse parentCollapseBefore = collapseInfo.GetCollapseBefore();
childCollapseBefore = ignoreChildTopMargin ? parentCollapseBefore : new MarginsCollapse();
}
else
{
MarginsCollapse prevChildCollapseAfter = prevChildMarginInfo != null?prevChildMarginInfo.GetOwnCollapseAfter
() : null;
childCollapseBefore = prevChildCollapseAfter != null ? prevChildCollapseAfter : new MarginsCollapse();
}
MarginsCollapse parentCollapseAfter = collapseInfo.GetCollapseAfter().Clone();
MarginsCollapse childCollapseAfter = ignoreChildBottomMargin ? parentCollapseAfter : new MarginsCollapse();
MarginsCollapseInfo childMarginsInfo = new MarginsCollapseInfo(ignoreChildTopMargin, ignoreChildBottomMargin
, childCollapseBefore, childCollapseAfter);
if (ignoreChildTopMargin && childIndex == firstNotEmptyKidIndex)
{
childMarginsInfo.SetBufferSpaceOnTop(collapseInfo.GetBufferSpaceOnTop());
}
if (ignoreChildBottomMargin)
{
childMarginsInfo.SetBufferSpaceOnBottom(collapseInfo.GetBufferSpaceOnBottom());
}
return(childMarginsInfo);
}
public MarginsCollapseHandler(IRenderer renderer, MarginsCollapseInfo marginsCollapseInfo)
{
this.renderer = renderer;
this.collapseInfo = marginsCollapseInfo != null ? marginsCollapseInfo : new MarginsCollapseInfo();
}