This provides internal features on _ASAsyncTransaction and ASDisplayNode to facilitate
implementing public API that allows clients to choose if they would prefer to block
on the completion of unfinished rendering, rather than allow a placeholder state to
become visible.
The internal features are:
-[_ASAsyncTransaction waitUntilComplete]
-[ASDisplayNode recursivelyEnsureDisplay]
Also provided are two such implementations:
-[ASCellNode setNeverShowPlaceholders:], which integrates with both Tables and Collections
-[ASViewController setNeverShowPlaceholders:], which should work with Nav and Tab controllers.
Lastly, on ASDisplayNode, a new property .shouldBypassEnsureDisplay allows individual node types
to exempt themselves from blocking the main thread on their display.
By implementing the feature at the ASCellNode level rather than ASTableView & ASCollectionView,
developers can retain fine-grained control on display characteristics. For example, certain
cell types may be appropriate to display to the user with placeholders, whereas others may not.
Follow-up work will include unit tests, revisiting names, and the header locations of definitions.
Eases support for nesting horizontally scrolling elements within a vertical scroller.
Further changes will improve the API, and optimize handling of the nested working ranges.
- 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).
ASNetworkImageNode defers to ASImageNode to return its calculatedSize. ASImageNode returns the size of its image. There is a good chance that ASNetworkImageNode hasn't downloaded its image yet when calculatedSize is called, so it returns a size of CGSizeZero.
On top of that, it is possible that the size of the image is not actually the size that we wish to display in our node.
I've added an "expectedImageSize" property that can be used to determine the calculatedSize of an ASNetworkImageNode.
