The rationale here is that every cell in an area needs to have space
reserved around it, requests have to be fully margin inclusive...
cells need to have the full size fed as the "background area" and
the "cell area" has margins removed... This will be used by GtkTreeViewColumn
to set the focus line width so that cells can paint a background on the
full background, then render themselves into the cell area... and parents
can go ahead and draw focus and other indicators on the background area
but outside of the cell area.
Added get_allocated_cells() which returns a practical list
of cells with allocation for render/event time, this abstracts
whether the cells are individually aligned or aligned into groups,
when there are groups of cells before an alignment, those groups
get allocated on the fly for render time.
Also fixed GtkCellAreaBox to track the iters it creates and flush
them when the overall layout configuration changes (add/remove/reorder/
spacing changed etc).
Added the following to GtkCellAreaBox:
- GtkCellAreaBox:spacing property defines spacing between cells
- GtkCellAreaBox:align-cells property defines whether cells should
be aligned with cells in adjacent rows.
- Implementations for get_preferred_width / get_preferred_height
- Implementations for get_preferred_height_for_width and the other
when the box is oriented in the easy way (i.e. height_for_width()
implemented for a vertical box, no virtual allocations done yet).
Added base class to hold alignment and overall size request information
while itterating over the size requests of various rows of a GtkTreeModel,
updated GtkCellArea/GtkCellAreaBox classes accordingly.
Added the child list to GtkCellAreaBox, added _pack_start() and
_pack_end() apis to GtkCellAreaBox since they are appropriate there
and implemented GtkCellLayoutIface to override the _pack_start()/end()
methods (since the base GtkCellArea class simply forwards these apis
to the generic ->add() api on the base class).
Now GtkCellArea handles attribute connections in the base class,
subclasses only need to add/remove the renderers, render them,
do geometry and handle events.
Now GtkCellArea provides a generic way of applying attributes
from a GtkTreeModel/GtkTreeIter, GtkCellArea bookkeeps a hashtable
of GtkCellLayoutDataFunc's and completely abstracts the applying
of data to cells... GtkCellArea implementations need only to bookkeep
the added renderers and attributes (probably we can abstract the
attribute bookkeeping in the base class as well).
Things starting to take a good and practical shape.
