Swiftgram/AsyncDisplayKit/ASDisplayNode+Beta.h
appleguy f91265757e [Yoga] Initial commit for supporting Yoga-powered layout calculation. (#2982)
* [Yoga + AsyncDisplayKit] Initial commit for supporting Yoga-powered layout calculation.

Because this results in ASLayout objects, it preserve support for automaticallyManagesSubnodes
as well as the animated transition system. More work remains to vet performance of the new mode,
and it will remain in +Beta for the forseeable future.

I'm not sure that this should ever be used as the primary ASDK layout system, but it should remain an
option for some apps to experiment with if they require an implementation that more strictly mirrors
W3C standard Flexbox.

* [Yoga] Improve usage of ASHierarchyState to ensure simultaneous yoga layouts can't happen.

* [Yoga] Strictly minimize the impact of the Yoga integration on existing code.

Created new file ASDisplayNode+Yoga.mm, reduced size and number of integration points in core code.

* [Yoga] Figured out how to further reduce ASDisplayNode.mm impact by allocating _yogaNode in property accessor, and changing all accesses to use the property.
2017-02-09 16:10:29 -08:00

186 lines
8.1 KiB
Objective-C

//
// ASDisplayNode+Beta.h
// AsyncDisplayKit
//
// Copyright (c) 2014-present, Facebook, Inc. All rights reserved.
// This source code is licensed under the BSD-style license found in the
// LICENSE file in the root directory of this source tree. An additional grant
// of patent rights can be found in the PATENTS file in the same directory.
//
#import <AsyncDisplayKit/ASAvailability.h>
#import <AsyncDisplayKit/ASDisplayNode.h>
#import <AsyncDisplayKit/ASLayoutRangeType.h>
#import <AsyncDisplayKit/ASEventLog.h>
NS_ASSUME_NONNULL_BEGIN
ASDISPLAYNODE_EXTERN_C_BEGIN
void ASPerformBlockOnMainThread(void (^block)());
void ASPerformBlockOnBackgroundThread(void (^block)()); // DISPATCH_QUEUE_PRIORITY_DEFAULT
ASDISPLAYNODE_EXTERN_C_END
#if ASEVENTLOG_ENABLE
#define ASDisplayNodeLogEvent(node, ...) [node.eventLog logEventWithBacktrace:(AS_SAVE_EVENT_BACKTRACES ? [NSThread callStackSymbols] : nil) format:__VA_ARGS__]
#else
#define ASDisplayNodeLogEvent(node, ...)
#endif
#if ASEVENTLOG_ENABLE
#define ASDisplayNodeGetEventLog(node) node.eventLog
#else
#define ASDisplayNodeGetEventLog(node) nil
#endif
/**
* Bitmask to indicate what performance measurements the cell should record.
*/
typedef NS_OPTIONS(NSUInteger, ASDisplayNodePerformanceMeasurementOptions) {
ASDisplayNodePerformanceMeasurementOptionLayoutSpec = 1 << 0,
ASDisplayNodePerformanceMeasurementOptionLayoutComputation = 1 << 1
};
typedef struct {
CFTimeInterval layoutSpecTotalTime;
NSInteger layoutSpecNumberOfPasses;
CFTimeInterval layoutComputationTotalTime;
NSInteger layoutComputationNumberOfPasses;
} ASDisplayNodePerformanceMeasurements;
@interface ASDisplayNode (Beta)
/**
* ASTableView and ASCollectionView now throw exceptions on invalid updates
* like their UIKit counterparts. If YES, these classes will log messages
* on invalid updates rather than throwing exceptions.
*
* Note that even if AsyncDisplayKit's exception is suppressed, the app may still crash
* as it proceeds with an invalid update.
*
* This property defaults to NO. It will be removed in a future release.
*/
+ (BOOL)suppressesInvalidCollectionUpdateExceptions AS_WARN_UNUSED_RESULT ASDISPLAYNODE_DEPRECATED_MSG("Collection update exceptions are thrown if assertions are enabled.");
+ (void)setSuppressesInvalidCollectionUpdateExceptions:(BOOL)suppresses ASDISPLAYNODE_DEPRECATED_MSG("Collection update exceptions are thrown if assertions are enabled.");;
/**
* @abstract Recursively ensures node and all subnodes are displayed.
* @see Full documentation in ASDisplayNode+FrameworkPrivate.h
*/
- (void)recursivelyEnsureDisplaySynchronously:(BOOL)synchronously;
/**
* @abstract allow modification of a context before the node's content is drawn
*
* @discussion Set the block to be called after the context has been created and before the node's content is drawn.
* You can override this to modify the context before the content is drawn. You are responsible for saving and
* restoring context if necessary. Restoring can be done in contextDidDisplayNodeContent
* This block can be called from *any* thread and it is unsafe to access any UIKit main thread properties from it.
*/
@property (nonatomic, copy, nullable) ASDisplayNodeContextModifier willDisplayNodeContentWithRenderingContext;
/**
* @abstract allow modification of a context after the node's content is drawn
*/
@property (nonatomic, copy, nullable) ASDisplayNodeContextModifier didDisplayNodeContentWithRenderingContext;
/**
* @abstract A bitmask representing which actions (layout spec, layout generation) should be measured.
*/
@property (nonatomic, assign) ASDisplayNodePerformanceMeasurementOptions measurementOptions;
/**
* @abstract A simple struct representing performance measurements collected.
*/
@property (nonatomic, assign, readonly) ASDisplayNodePerformanceMeasurements performanceMeasurements;
#if ASEVENTLOG_ENABLE
/*
* @abstract The primitive event tracing object. You shouldn't directly use it to log event. Use the ASDisplayNodeLogEvent macro instead.
*/
@property (nonatomic, strong, readonly) ASEventLog *eventLog;
#endif
/**
* @abstract Currently used by ASNetworkImageNode and ASMultiplexImageNode to allow their placeholders to stay if they are loading an image from the network.
* Otherwise, a display pass is scheduled and completes, but does not actually draw anything - and ASDisplayNode considers the element finished.
*/
- (BOOL)placeholderShouldPersist AS_WARN_UNUSED_RESULT;
/**
* @abstract Indicates that the receiver and all subnodes have finished displaying. May be called more than once, for example if the receiver has
* a network image node. This is called after the first display pass even if network image nodes have not downloaded anything (text would be done,
* and other nodes that are ready to do their final display). Each render of every progressive jpeg network node would cause this to be called, so
* this hook could be called up to 1 + (pJPEGcount * pJPEGrenderCount) times. The render count depends on how many times the downloader calls the
* progressImage block.
*/
- (void)hierarchyDisplayDidFinish;
/**
* Only ASLayoutRangeModeVisibleOnly or ASLayoutRangeModeLowMemory are recommended. Default is ASLayoutRangeModeVisibleOnly,
* because this is the only way to ensure an application will not have blank / flashing views as the user navigates back after
* a memory warning. Apps that wish to use the more effective / aggressive ASLayoutRangeModeLowMemory may need to take steps
* to mitigate this behavior, including: restoring a larger range mode to the next controller before the user navigates there,
* enabling .neverShowPlaceholders on ASCellNodes so that the navigation operation is blocked on redisplay completing, etc.
*/
+ (void)setRangeModeForMemoryWarnings:(ASLayoutRangeMode)rangeMode;
/**
* @abstract Whether to draw all descendant nodes' layers/views into this node's layer/view's backing store.
*
* @discussion
* When set to YES, causes all descendant nodes' layers/views to be drawn directly into this node's layer/view's backing
* store. Defaults to NO.
*
* If a node's descendants are static (never animated or never change attributes after creation) then that node is a
* good candidate for rasterization. Rasterizing descendants has two main benefits:
* 1) Backing stores for descendant layers are not created. Instead the layers are drawn directly into the rasterized
* container. This can save a great deal of memory.
* 2) Since the entire subtree is drawn into one backing store, compositing and blending are eliminated in that subtree
* which can help improve animation/scrolling/etc performance.
*
* Rasterization does not currently support descendants with transform, sublayerTransform, or alpha. Those properties
* will be ignored when rasterizing descendants.
*
* Note: this has nothing to do with -[CALayer shouldRasterize], which doesn't work with ASDisplayNode's asynchronous
* rendering model.
*/
@property (nonatomic, assign) BOOL shouldRasterizeDescendants;
@end
#pragma mark - Yoga Layout Support
#if YOGA
@interface ASDisplayNode (Yoga)
@property (nonatomic, strong) NSArray *yogaChildren;
- (void)addYogaChild:(ASDisplayNode *)child;
- (void)removeYogaChild:(ASDisplayNode *)child;
// This method should not normally be called directly.
- (ASLayout *)calculateLayoutFromYogaRoot:(ASSizeRange)rootConstrainedSize;
@end
@interface ASLayoutElementStyle (Yoga)
@property (nonatomic, assign, readwrite) ASStackLayoutDirection direction;
@property (nonatomic, assign, readwrite) CGFloat spacing;
@property (nonatomic, assign, readwrite) ASStackLayoutJustifyContent justifyContent;
@property (nonatomic, assign, readwrite) ASStackLayoutAlignItems alignItems;
@property (nonatomic, assign, readwrite) YGPositionType positionType;
@property (nonatomic, assign, readwrite) ASEdgeInsets position;
@property (nonatomic, assign, readwrite) ASEdgeInsets margin;
@property (nonatomic, assign, readwrite) ASEdgeInsets padding;
@property (nonatomic, assign, readwrite) ASEdgeInsets border;
@property (nonatomic, assign, readwrite) CGFloat aspectRatio;
@property (nonatomic, assign, readwrite) YGWrap flexWrap;
@end
#endif
NS_ASSUME_NONNULL_END