This should not directly affect more complex apps that don't use the ASBasicImageDownloader.
Also disables the default-on text placeholders, as they churn memory during the measurement pass.
These were intended to be written with pure layers (without using backing stores), so I don't
think it is a reasonable default-on behavior until that is fixed.
- Cell node automatically notifies the delegate after a relayout (via -setNeedsLayout) that results in a new size. Confirming to ASCellNodeDelegate; ASTableView and ASCollectionView reload the calling cell upon notifications. These views automatically set themselves as delegate of every node.
- The result is that ASCellNode subclasses don't need to manually notify the containing view. Thus, `-relayoutItemAtIndexPath` and `-relayoutRowAtIndexPath` are removed.
- Kittens example is updated to reflect the change.
- In -layoutSubviews of table and collection views, detect changes that cause a different constrained size for nodes, and trigger relayout immediately.
- Orientation change can be handled by this solution. So, no need to observe to its events.
- Update Kittens example to support iPad (easier to catch bugs on these devices) and add a title to navigation bar (looks a bit nicer).
In particular, the NSValue-boxed CGSize array used as a data model for the kittens
is generated with random sizes, for unclear reasons. It turns out this is a workaround
to convince PlaceKitten to send us unique images.
ASDisplayNode and several subclasses had previously cleared memory-heavy
objects like the backing store and text layout manager when the node's
view
or layer is removed from a visible heirarchy. This works great in any
system
that uses a "working range", where exiting the range removes the node
from
the hierarchy and reclaiming memory at that time is important.
However, for
standard UIViewController patterns (unused in Paper), this behavior
causes
highly undesirable thrashing (leading to visible flashes & wasteful
re-rendering of content).
After this change, node subclasses should implement -reclaimMemory if
they
need to perform any other cleanup besides backing store destruction
when they
leave a working range or other scenario where memory reduction is
valuable.
To trigger this behavior, calling code should use
-recursivelyReclaimMemory.
r=nadi
