How do I update annotation modified date?

Q: I am using PDFViewCtrl and adding annotations. The modified date
for the annotation seems to be the date/time that the document was
opened, not when the annotation is created. Why? Also, I need a
handle to the most recently created annotation so that I can make
additional changes to it. I don't see any methods in PDFViewCtrl that
provide this so I tried to use the date value to determine which
annotation was created most recently but that doesn't work since they
all have the same value.
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A: PDFNet is not modifying these dates in each function since it would
not be efficient.

You can update the modification date as follows (assuming C++, other
languages are similar):

annot.Set...
annot.Set...
annot.Set...

Date now;
now.SetCurrentTime();
annot.SetDate(now);

to obtain the current date value use:

Date d = annot.GetDate(now);