Both are derived from SfxSetItem which means they contain a SfxItemSet themselves. That leads to problems since at their construction time a SfxItemPool has to be known and it *should* not be different to the one of the ItemSet that Item gets added later - that leads to the 2nd class of problems. In the long therm we should get rid of all SfxSetItems. This change simplifies already some stuff, including that the standard Items for DrawObjects reduces by two (and more due to containing a whole ItemSet) and e.g. the problem that these Items had to be converted to hard attributes in the done fixes for copy/pasting Slides. Signed-off-by: Armin Le Grand (collabora) <Armin.LeGrand@collabora.com> Change-Id: I8b1c6cabdaa43ed6062811b5508ab3dece47a755 Reviewed-on: https://gerrit.collaboraoffice.com/c/online/+/6795 Reviewed-by: Armin Le Grand <armin.legrand@collabora.com> Tested-by: Jenkins CPCI <releng@collaboraoffice.com> (cherry picked from commit e67458a9b769fe7a3a7ee0739ed6d5c46dbc0692) Reviewed-on: https://gerrit.libreoffice.org/c/core/+/211734 Tested-by: Jenkins Reviewed-by: Xisco Fauli <xiscofauli@libreoffice.org>
Non-Graphical Helper Code (svtools light)
Contains non-graphical helper code for office applications.
Specifically this module does not depend on or use includes from module vcl. Originally all code in svtools that did not depend on vcl was split off into this svl ("svtools light") module.
In particular the SfxItemSet is a property-bag like container that
stores arbitrary sets of properties for everything from text run
formats, to Chart regression line properties.
There are lots of other useful helpers in here for various office
tasks; much of this code was originally moved from svx/sfx2.
Items, Pools and Sets
SfxPoolItem
A small reference counted piece of data. Many subclasses, each with a
unique integer to identify its type (WhichId). Can be compared for equality
(operator==), Clone()d, and converted to/from uno::Any (QueryValue/PutValue).
A pool item may have value semantics ("poolable"), meaning that
there will generally be only one instance that compares equal per item pool,
or not, in which case the item will be Clone()d quite a bit.
SfxItemPool
Usually there is one item pool per document, with a range of valid WhichIds
that is specific to the type of document.
The item pool owns all instances of SfxPoolItem or its subclasses that have
ever been added to an item set. It also contains a default item for
every WhichId, which will be (depending on parameters) returned from item
sets if the set does not contain an item at this WhichId.
SfxItemSet
The item set can be created with a user-supplied range of WhichIds; it
will accept SfxPoolItems with matching WhichIds and ignore attempts to
insert items with non-matching WhichIds.
Items that are successfully inserted into the set will be stored in the
set's SfxItemPool, and for poolable items only a single instance that
compares equal under the predicate operator== will be stored in the pool,
regardless of how many sets contain it, thus conserving memory.
There are members m_pWhichRanges for the valid ranges (as pairs of WhichIds),
m_nCount for the number of items contained, and m_pItems for the pointers to
the actual items.