ASDisplayNodes now have an overidable method -placeholderImage that lets you provide a custom UIImage to display while a node is displaying asyncronously. The default implementation of this method returns nil and thus does nothing. A provided example project also demonstrates using the placeholder API.
Postpone manual display until a future release when it can be called on any thread. Provide the current node manual display logic as a category on ASDisplayNode only available for ASRangeController. Deprecate -displayImmediately.
ASDISPLAYNODE_DELAY_DISPLAY unconditionally delays *all* attempts to
execute display blocks, even those that have been cancelled. Fix that.
The DELAY_DISPLAY debugging tool is intended to simulate the effect of
expensive draw calls -- it lets you test your app's behaviour under
conditions potentially even worse than an iPhone 4. Unfortunately, the
current simulation is unusably incorrect, as can be demonstrated by
repeatedly scrolling up and down in the Kittens example project.
ASRangeController enqueues asynchronous display of ASTableView cell
nodes when they enter the working range, and suspends their display when
they exit. On a slow device, this performs as desired, limiting
expensive display computation to the space of the working range. In
the DELAY_DISPLAY simulation, the suspended displays are as expensive as
the executed ones, so ASRangeController becomes unusably slow.
Rename the ASDisplayNode property to match its _ASDisplayLayer
counterpart -- `displaySuspended` is more succinct and is a more
plausible name for a Cocoa BOOL property.
This is a remnant from before `willAppear` and `didDisappear` were
renamed to better reflect their hierarchy-change status (being added to
the hierarchy != being visible). May be useful for turians.
* Reorganise and rename `_flags` for clarity and consistency.
* Remove ambiguity between `implementsDisplay` and `hasClassDisplay`.
* Delete useless `hasWillDisplayAsyncLayer` check -- make it a simple
subclass override point, as with `didDisplayAsyncLayer:`.
* Minor comment cleanup.
Initial open-source release of ASMultiplexImageNode. Documentation and
example code forthcoming.
Note: ASMultiplexImageNode requires Xcode 6 to compile. Tests are now
compiled against the iOS 8 SDK and run on iOS 7.1 and iOS 8.
ASImageNode and ASHighlightOverlayLayer were both using
[[UIScreen mainScreen] scale] directly. Bad. No cookie. Use
ASDisplayNodeScreenScale() instead.
(Also, regenerate Xcode project with Xcode 6 and current CocoaPods.)
Fixes:
- Usage of UIScreen in -[ASDisplayNode init]
(the offending individual will be prosecuted)
- #38: Proper teardown of nodes owned by ASTableView / ASRangeController
- #34: Fix infinite recursion in very rare subclassing scenario
- #30: Avoid animating cell and section additions to ASTableView
- #19: Set a more reasonable default for maximum display concurrency
r=nadi
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
Introduce `ASTableView`, a UITableView subclass that uses `ASCellNode`
instead of UITableViewCell. Add working range support via
`ASRangeController`, which observes the visible range, maintains a
working range, and handles most ASDK machinery. ASRangeController is
loosely-enough coupled that it should be easily adapted to
UICollectionView if that's desired in the future.
Notable considerations in the ASRangeController architecture:
* There's no sense rewriting UITableView -- the real win comes from
using nodes instead of UITableViewCells (easily parallelisable
computation, large number of cells vs. few table views, etc.). So,
use a UITableView with empty cells, using UITableViewCell's
contentView as a host for arbitrary node hierarchies.
* Instead of lazy-loading cells the instant they're needed by
UITableView, load them in advance. Preload a substantial number of
nodes in the direction of scroll, as well as a small buffer in the
other direction.
* Maintain compatibility with UITableView's API, with one primary change
-- consumer code yields configured ASCellNodes, not UITableViewCells.
* Don't use -tableView:heightForRowAtIndexPath:. Nodes already compute
their preferred sizes and cache results for use at layout-time, so
ASTableView uses their calculatedSizes directly.
* Corollary: ASTableView is only aware of nodes that have been sized.
This means that, if a cell appears onscreen, it has layout data and
can display a "realistic placeholder", e.g. by making its subnodes'
background colour grey.
Other improvements:
* Remove dead references and update headers (fixes#7, #20).
* Rename `-[ASDisplayNode sizeToFit:]` to `-measure:` and fix
`constrainedSizeForCalulatedSize` typo (fixes#15).
* Rename `-willAppear` and `-didDisappear` to `-willEnterHierarchy` and
`-didExitHierarchy`. Remove `-willDisappear` -- it was redundant, and
there was no counterpart `-didAppear`.
* Rename `viewLoaded` to `nodeLoaded`.
Summary:
* Moves ASThread.h from Private to Public visibility
* Moves ASThread.h from Private/ to Details/
* Changes public #imports from "" to <>
Test Plan:
```
#import <AsyncDisplayKit/ASDisplayNode+Subclasses.h>
#import <AsyncDisplayKit/ASControlNode+Subclasses.h>
```
