* [ASDisplayNode] Convert isSynchronous to an Objective-C atomic BOOL.
This reduces lock contention, and should also fix a very rarely seen deadlock.
* [ASDisplayNode] Implement a std::atomic-based flag system for superb performance
Although Objective-C atomics are equally fast, or better that std::atomic when
access through method calls, for the most intense use cases it is best to avoid
method calls entirely.
In ASDisplayNode, we could benefit significantly from avoiding both method calls
(already true today) but also avoid locking the mutex, for both CPU and contention
gains.
There will still be many methods that need locking for transactional
consistency - however, there are currently dozens of accessor methods that could
avoid frequent lock / unlock cycles with use of atomics, and other usages of the
ivars directly where locking could be delayed until after early-return conditions
are checked and passed.
* Add a thread-safe layoutIfNeeded implementation to ASDisplayNode
* Trigger a layout pass when a display node enters preload state
- This ensures that all the subnodes have the correct size to preload their content.
* ASCollectionNode to trigger its initial data load when it enters preload state
* Minor change in _ASCollectionViewCell
* Layout sublayouts before dispatch to main for subclass hooks
* Update comments
* Don't wait until updates are committed when the collection node enters display state
* Same deal for table node
* Explain the layout trigger in ASDisplayNode
* Introduce ASCollectionViewLayout
- `ASCollectionViewLayout` is an async `UICollectionViewLayout` that encapsulates its layout calculation logic into a separate thread-safe object which can be used ahead of time and/or on multiple threads.
- `ASDataController` now can prepare for a new layout resulted from a change set before `ASCollectionView` even knows about it. By the time the change set it ready to be consumed by `ASCollectionView`, its new layout is also ready.
- New `ASCollectionViewLayoutCalculating` protocol that is simple and generic enough that many types of calculators can be built on top. `ASCollectionViewLayoutSpecCalculator` conforms to `ASCollectionViewLayoutCalculating` protocol and can be backed by any layout spec (e.g `ASStackLayoutSpec`, `PIMasonryLayoutSpec`, etc). We can even build a `ASCollectionViewLayoutYogaCalculator` that uses Yoga internally.
- A built-in `ASCollectionViewFlowLayoutCalculator` that is a subclass of `ASCollectionViewLayoutSpecCalculator` and uses a multi-threaded multi-line `ASStackLayoutSpec` internally. The result is a performant and thread-safe flow layout calculator.
- Finally, `ASCollectionViewLayout` can be subclassed to handle a specific type of calculator with optimizations implemented based on the knowledge of such calculator. For example, `ASCollectionViewFlowLayout` can have a highly optimized implementation of `-layoutAttributesForElementsInRect:`.
Protocolize layout calculator providing and consuming
Add flex wrap documentation
Add a `multithreaded` flag to ASStackLayoutSpec that forces it to dispatch even if it's off main
- Update ASCollectionViewFlowLayoutSpecCalculator to use that flag.
Minor change in ASCollectionViewLayout
Implement Mosaic layout calculator
Minor change
Fix project file
Rename and fix project file
Skip fetching constrained size only if a layout calculator is available
Update examples/ASCollectionView
Remove unnecessary change in ASTableView
Address comments
Rename collection view calculator protocols
Minor changes after rebasing with master
Add ASLegacyCollectionLayoutCalculator for backward compatibility
Remove ASCollectionLayoutSpecCalculator
Remove ASLegacyCollectionLayoutCalculator
Introduce ASCollectionLayout
- A wrapper object that contains content size and an element to rect table.
- Collection layout calculators to return this new object instead of an ASLayout.
Before adding a content cache
Finishing hooking up ASCollectionLayoutDataSource to ASCollectionNode
Stash
Finish ASCollectionLayout
Rough impl of ASCollectionFlowLayout
Revert changes in CustomCollectionView example
Move ASRectTable back to Private
* Rename ASCollectionContentAttributes to ASCollectionLayoutState
* Address other comments
* Introduce ASCollectionLayoutDelegate and make ASCollectionLayout private
* Address comments
* API tweaks:
- Replace `-layoutContextWithElementMap:` in ASCollectionLayoutDelegate with `-additionalInfoForLayoutWithElements:`. The returned object is then stored in ASCollectionLayoutContext for later lookups.
- ASCollectionLayoutContext has no public initializer.
- ASDataControllerLayoutDelegate no longer requires a context of type ASCollectionLayoutContext but simply an `id`. This helps decouple ASDataController and ASCollectionLayout.
- Rename `elementMap` to `elements`.
- Rename `visibleMap` to `visibleElements`.
- Other minor changes.
* Rename ASCGSizeHash to ASHashFromCGSize
* Make sure to call super in -[ASCollectionLayout prepareLayout]
* Update example/ASCollectionView to use ASCollectionFlowLayoutDelegate
* Remove unnecessary change
- It's not safe to hold the lock of a supernode and:
- Edit states of its subnodes
- Call subclass hooks
- Run completion block
- Run animation, which can trigger layout passes on subnodes, especially if one of them is a collection view.
We have to check in this case if the supernode of the subnode is indeed the _node that executes a layout transition. It can happen that a node already did a layout transition and added this subnode, in this case the subnode would would be removed from the new node instead of _node.
- Before this commit:
- Bridged properties are accessed to construct a recursive description without considering thread affinity.
- We have multiple methods that does the same thing: generates a debug description.
- After this commit:
- Bridged properties are accessed without triggering thread affinity assertions.
- We have only one method that provides debug description of a node. It is then used to construct a recursive description.
* Set the node to not opaque if it’s wrapping an UIActivityIndicatorView
* Add check for subclass of UIVisualEffectView to see if the node needs to be opaque
* New way to informing interaction delegate if ASCellNode get’s a setNeedsLayout call
* Remove nodeDidGetNeedsLayout as optional and better check if cell updates need to happen
* Differentiate between letting a normal display node and a cell node know that the size could have changed
* Check for _interactionDelegate is nil
* Add nullability to out pointer
* Adress comments and some renaming
