3e5b8c3096
Scenario: An ASCollectionNode is a subnode of an ASCellNode. A layout transition is started, resulting in the removal of the ASCollectionNode as a subnode. As it is removed, the hierarchy state is cleared - including the "range managed" bit - on the ASCollectionNode. However, the deep recursion traverses the layer hierarchy too, and clears this bit on the ASCellNodes inside the ASCollectionNode. A moment later, the collection performs its final ASRangeController update to mark its cells as invisible and free memory. Then an assertion is triggered in ASRangeController, because it is operating on nodes that do not have the "range managed" bit set. It turns out that ASInterfaceState also propogates in this way, but that behavior is efficient and beneficial in its current configuration (it assists how multi-dimensional preloading works). However, hierarchy state should never need to jump discontinuities in the node hierarchy. For now, disabling that case and will revisit other use cases soon.
Installation
ASDK is available via CocoaPods or Carthage. See our Installation guide for instructions.
Performance Gains
AsyncDisplayKit's basic unit is the node. An ASDisplayNode is an abstraction over UIView, which in turn is an abstraction over CALayer. Unlike views, which can only be used on the main thread, nodes are thread-safe: you can instantiate and configure entire hierarchies of them in parallel on background threads.
To keep its user interface smooth and responsive, your app should render at 60 frames per second — the gold standard on iOS. This means the main thread has one-sixtieth of a second to push each frame. That's 16 milliseconds to execute all layout and drawing code! And because of system overhead, your code usually has less than ten milliseconds to run before it causes a frame drop.
AsyncDisplayKit lets you move image decoding, text sizing and rendering, layout, and other expensive UI operations off the main thread, to keep the main thread available to respond to user interaction.
Advanced Developer Features
As the framework has grown, many features have been added that can save developers tons of time by eliminating common boilerplate style structures common in modern iOS apps. If you've ever dealt with cell reuse bugs, tried to performantly preload data for a page or scroll style interface or even just tried to keep your app from dropping too many frames you can benefit from integrating ASDK.
Learn More
- Read the our Getting Started guide
- Get the sample projects
- Browse the API reference
Getting Help
We use Slack for real-time debugging, community updates, and general talk about ASDK. Signup youself or email AsyncDisplayKit(at)gmail.com to get an invite.
Contributing
We welcome any contributions. See the CONTRIBUTING file for how to get involved.
License
AsyncDisplayKit is BSD-licensed. We also provide an additional patent grant. The files in the /examples directory are licensed under a separate license as specified in each file; documentation is licensed CC-BY-4.0.