public override void Draw(DrawContext drawContext)
{
LayoutTaggingHelper taggingHelper = GetProperty <LayoutTaggingHelper>(Property.TAGGING_HELPER);
// We want to reach the actual tag from logical structure tree, in order to set custom properties, for
// which iText doesn't provide convenient API at the moment. Specifically we are aiming at setting /ID
// entry in structure element dictionary corresponding to the table header cell. Here we are creating tag
// for the current element in logical structure tree right at the beginning of #draw method.
// If this particular instance of header cell is paging artifact it would be marked so by layouting
// engine and it would not allow to create a tag (return value of the method would be 'false').
// If this particular instance of header cell is the header which is to be tagged, a tag will be created.
// It's safe to create a tag at this moment, it will be picked up and placed at correct position in the
// logical structure tree later by layout engine.
TagTreePointer p = new TagTreePointer(pdfDocument);
if (taggingHelper.CreateTag(this, p))
{
// After the tag is created, we can fetch low level entity PdfStructElem
// in order to work with it directly. These changes would be directly reflected
// in the PDF file inner structure.
PdfStructElem structElem = tagContext.GetPointerStructElem(p);
PdfDictionary structElemDict = structElem.GetPdfObject();
structElemDict.Put(PdfName.ID, headerId);
idTree.AddEntry(headerId.GetValue(), structElemDict);
}
base.Draw(drawContext);
}
public virtual void AddKidsHint <_T0>(TagTreePointer parentPointer, IEnumerable <_T0> newKids)
where _T0 : IPropertyContainer
{
PdfDictionary pointerStructElem = context.GetPointerStructElem(parentPointer).GetPdfObject();
TaggingDummyElement dummy = existingTagsDummies.Get(pointerStructElem);
if (dummy == null)
{
dummy = new TaggingDummyElement(parentPointer.GetRole());
existingTagsDummies.Put(pointerStructElem, dummy);
}
context.GetWaitingTagsManager().AssignWaitingState(parentPointer, GetOrCreateHintKey(dummy));
AddKidsHint(dummy, newKids);
}