Add the ability for ASNetworkImageNodes to keep track of their progressive image quality

AsyncDisplayKit.xcodeproj/project.pbxproj

@@ -337,6 +337,10 @@
 		9CDC18CC1B910E12004965E2 /* ASLayoutablePrivate.h in Headers */ = {isa = PBXBuildFile; fileRef = 9CDC18CB1B910E12004965E2 /* ASLayoutablePrivate.h */; settings = {ATTRIBUTES = (Public, ); }; };
 		9CDC18CD1B910E12004965E2 /* ASLayoutablePrivate.h in Headers */ = {isa = PBXBuildFile; fileRef = 9CDC18CB1B910E12004965E2 /* ASLayoutablePrivate.h */; settings = {ATTRIBUTES = (Public, ); }; };
 		9F06E5CD1B4CAF4200F015D8 /* ASCollectionViewTests.m in Sources */ = {isa = PBXBuildFile; fileRef = 9F06E5CC1B4CAF4200F015D8 /* ASCollectionViewTests.m */; };
+		A2763D791CBDD57D00A9ADBD /* ASPINRemoteImageDownloader.h in Headers */ = {isa = PBXBuildFile; fileRef = A2763D771CBDD57D00A9ADBD /* ASPINRemoteImageDownloader.h */; };
+		A2763D7A1CBDD57D00A9ADBD /* ASPINRemoteImageDownloader.h in Headers */ = {isa = PBXBuildFile; fileRef = A2763D771CBDD57D00A9ADBD /* ASPINRemoteImageDownloader.h */; };
+		A2763D7B1CBDD57D00A9ADBD /* ASPINRemoteImageDownloader.m in Sources */ = {isa = PBXBuildFile; fileRef = A2763D781CBDD57D00A9ADBD /* ASPINRemoteImageDownloader.m */; };
+		A2763D7C1CBDD57D00A9ADBD /* ASPINRemoteImageDownloader.m in Sources */ = {isa = PBXBuildFile; fileRef = A2763D781CBDD57D00A9ADBD /* ASPINRemoteImageDownloader.m */; };
 		A32FEDD51C501B6A004F642A /* ASTextKitFontSizeAdjuster.h in Headers */ = {isa = PBXBuildFile; fileRef = A32FEDD31C501B6A004F642A /* ASTextKitFontSizeAdjuster.h */; settings = {ATTRIBUTES = (Public, ); }; };
 		A373200F1C571B730011FC94 /* ASTextNode+Beta.h in Headers */ = {isa = PBXBuildFile; fileRef = A373200E1C571B050011FC94 /* ASTextNode+Beta.h */; settings = {ATTRIBUTES = (Public, ); }; };
 		A37320101C571B740011FC94 /* ASTextNode+Beta.h in Headers */ = {isa = PBXBuildFile; fileRef = A373200E1C571B050011FC94 /* ASTextNode+Beta.h */; settings = {ATTRIBUTES = (Public, ); }; };
@@ -808,6 +812,8 @@
 		9C8898BA1C738B9800D6B02E /* ASTextKitFontSizeAdjuster.mm */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.cpp.objcpp; name = ASTextKitFontSizeAdjuster.mm; path = TextKit/ASTextKitFontSizeAdjuster.mm; sourceTree = "<group>"; };
 		9CDC18CB1B910E12004965E2 /* ASLayoutablePrivate.h */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.h; name = ASLayoutablePrivate.h; path = AsyncDisplayKit/Layout/ASLayoutablePrivate.h; sourceTree = "<group>"; };
 		9F06E5CC1B4CAF4200F015D8 /* ASCollectionViewTests.m */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.objc; lineEnding = 0; path = ASCollectionViewTests.m; sourceTree = "<group>"; xcLanguageSpecificationIdentifier = xcode.lang.objc; };
+		A2763D771CBDD57D00A9ADBD /* ASPINRemoteImageDownloader.h */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.h; name = ASPINRemoteImageDownloader.h; path = Details/ASPINRemoteImageDownloader.h; sourceTree = "<group>"; };
+		A2763D781CBDD57D00A9ADBD /* ASPINRemoteImageDownloader.m */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.objc; name = ASPINRemoteImageDownloader.m; path = Details/ASPINRemoteImageDownloader.m; sourceTree = "<group>"; };
 		A32FEDD31C501B6A004F642A /* ASTextKitFontSizeAdjuster.h */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.h; name = ASTextKitFontSizeAdjuster.h; path = TextKit/ASTextKitFontSizeAdjuster.h; sourceTree = "<group>"; };
 		A373200E1C571B050011FC94 /* ASTextNode+Beta.h */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.c.h; path = "ASTextNode+Beta.h"; sourceTree = "<group>"; };
 		AC026B571BD3F61800BBC17E /* ASStaticLayoutSpecSnapshotTests.m */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.objc; path = ASStaticLayoutSpecSnapshotTests.m; sourceTree = "<group>"; };
@@ -1064,6 +1070,8 @@
 				055B9FA71A1C154B00035D6D /* ASNetworkImageNode.mm */,
 				25E327541C16819500A2170C /* ASPagerNode.h */,
 				25E327551C16819500A2170C /* ASPagerNode.m */,
+				A2763D771CBDD57D00A9ADBD /* ASPINRemoteImageDownloader.h */,
+				A2763D781CBDD57D00A9ADBD /* ASPINRemoteImageDownloader.m */,
 				D785F6601A74327E00291744 /* ASScrollNode.h */,
 				D785F6611A74327E00291744 /* ASScrollNode.m */,
 				B0F880581BEAEC7500D17647 /* ASTableNode.h */,
@@ -1461,6 +1469,7 @@
 				058D0A72195D05F800B7D73C /* _ASCoreAnimationExtras.h in Headers */,
 				7A06A73B1C35F08800FE8DAA /* ASRelativeLayoutSpec.h in Headers */,
 				68B8A4DC1CBD911D007E4543 /* ASImageNode+AnimatedImagePrivate.h in Headers */,
+				A2763D791CBDD57D00A9ADBD /* ASPINRemoteImageDownloader.h in Headers */,
 				058D0A53195D05DC00B7D73C /* _ASDisplayLayer.h in Headers */,
 				058D0A55195D05DC00B7D73C /* _ASDisplayView.h in Headers */,
 				B13CA0F71C519E9400E031AB /* ASCollectionViewLayoutFacilitatorProtocol.h in Headers */,
@@ -1620,6 +1629,7 @@
 				B35062581B010F070018CF92 /* ASAvailability.h in Headers */,
 				DE84918D1C8FFF2B003D89E9 /* ASRunLoopQueue.h in Headers */,
 				254C6B731BF94DF4003EC431 /* ASTextKitCoreTextAdditions.h in Headers */,
+				A2763D7A1CBDD57D00A9ADBD /* ASPINRemoteImageDownloader.h in Headers */,
 				254C6B7A1BF94DF4003EC431 /* ASTextKitRenderer.h in Headers */,
 				69CB62AC1CB8165900024920 /* _ASDisplayViewAccessiblity.h in Headers */,
 				68355B3F1CB57A64001D4E68 /* ASPINRemoteImageDownloader.h in Headers */,

AsyncDisplayKit/ASDisplayNode+Beta.h

@@ -103,4 +103,13 @@ ASDISPLAYNODE_EXTERN_C_END
  */
 - (void)cancelLayoutTransitionsInProgress;
 
+/**
+ * @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;
+
 @end

AsyncDisplayKit/ASDisplayNode.mm

@@ -1722,19 +1722,23 @@ static NSInteger incrementIfFound(NSInteger i) {
 
   [_pendingDisplayNodes removeObject:node];
 
-  if (_pendingDisplayNodes.count == 0 && _placeholderLayer.superlayer && ![self placeholderShouldPersist]) {
-    void (^cleanupBlock)() = ^{
-      [_placeholderLayer removeFromSuperlayer];
-    };
+  if (_pendingDisplayNodes.count == 0) {
+    [self hierarchyDisplayDidFinish];
+    
+    if (_placeholderLayer.superlayer && ![self placeholderShouldPersist]) {
+      void (^cleanupBlock)() = ^{
+        [_placeholderLayer removeFromSuperlayer];
+      };
 
-    if (_placeholderFadeDuration > 0.0 && ASInterfaceStateIncludesVisible(self.interfaceState)) {
-      [CATransaction begin];
-      [CATransaction setCompletionBlock:cleanupBlock];
-      [CATransaction setAnimationDuration:_placeholderFadeDuration];
-      _placeholderLayer.opacity = 0.0;
-      [CATransaction commit];
-    } else {
-      cleanupBlock();
+      if (_placeholderFadeDuration > 0.0 && ASInterfaceStateIncludesVisible(self.interfaceState)) {
+        [CATransaction begin];
+        [CATransaction setCompletionBlock:cleanupBlock];
+        [CATransaction setAnimationDuration:_placeholderFadeDuration];
+        _placeholderLayer.opacity = 0.0;
+        [CATransaction commit];
+      } else {
+        cleanupBlock();
+      }
     }
   }
 }
@@ -2390,6 +2394,11 @@ void recursivelyTriggerDisplayForLayer(CALayer *layer, BOOL shouldBlock)
   });
 }
 
+- (void)hierarchyDisplayDidFinish
+{
+  // subclass hook
+}
+
 - (void)touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event
 {
   // subclass hook

AsyncDisplayKit/ASMultiplexImageNode.mm

@@ -469,7 +469,7 @@ typedef void(^ASMultiplexImageLoadCompletionBlock)(UIImage *image, id imageIdent
     ASImageDownloaderProgressImage progress = nil;
     if (ASInterfaceStateIncludesVisible(interfaceState)) {
         __weak __typeof__(self) weakSelf = self;
-        progress = ^(UIImage * _Nonnull progressImage, id _Nullable downloadIdentifier) {
+        progress = ^(UIImage * _Nonnull progressImage, CGFloat progress, id _Nullable downloadIdentifier) {
             __typeof__(self) strongSelf = weakSelf;
             if (strongSelf == nil) {
                 return;

AsyncDisplayKit/ASNetworkImageNode.h

@@ -73,6 +73,17 @@ NS_ASSUME_NONNULL_BEGIN
  */
 @property (nonatomic, assign, readwrite) BOOL shouldCacheImage;
 
+/**
+ * The image quality of the current image. This is a number between 0 and 1 and can be used to track
+ * progressive progress. Calculated by dividing number of bytes / expected number of total bytes.
+ */
+@property (nonatomic, assign, readonly) CGFloat currentImageQuality;
+
+/**
+ * The image quality (value between 0 and 1) of the last image that completed displaying.
+ */
+@property (nonatomic, assign, readonly) CGFloat renderedImageQuality;
+
 @end
 
 

AsyncDisplayKit/ASNetworkImageNode.mm

@@ -39,17 +39,19 @@ static const CGSize kMinReleaseImageOnBackgroundSize = {20.0, 20.0};
   id _downloadIdentifier;
 
   BOOL _imageLoaded;
-  
+  CGFloat _currentImageQuality;
+  CGFloat _renderedImageQuality;
+
   BOOL _delegateSupportsDidStartFetchingData;
   BOOL _delegateSupportsDidFailWithError;
   BOOL _delegateSupportsImageNodeDidFinishDecoding;
-  
+
   //set on init only
   BOOL _downloaderSupportsNewProtocol;
   BOOL _downloaderImplementsSetProgress;
   BOOL _downloaderImplementsSetPriority;
   BOOL _downloaderImplementsAnimatedImage;
-  
+
   BOOL _cacheSupportsNewProtocol;
   BOOL _cacheSupportsClearing;
   BOOL _cacheSupportsSynchronousFetch;
@@ -120,9 +122,13 @@ static const CGSize kMinReleaseImageOnBackgroundSize = {20.0, 20.0};
 
   _URL = URL;
 
-  if (reset || _URL == nil)
+  if (reset || _URL == nil) {
     self.image = _defaultImage;
-  
+    ASPerformBlockOnMainThread(^{
+      _currentImageQuality = 0.0;
+    });
+  }
+
   if (self.interfaceState & ASInterfaceStateFetchData) {
     [self fetchData];
   }
@@ -145,6 +151,9 @@ static const CGSize kMinReleaseImageOnBackgroundSize = {20.0, 20.0};
   _defaultImage = defaultImage;
 
   if (!_imageLoaded) {
+    ASPerformBlockOnMainThread(^{
+      _currentImageQuality = 0.0;
+    });
     _lock.unlock();
     // Locking: it is important to release _lock before entering setImage:, as it needs to release the lock before -invalidateCalculatedLayout.
     // If we continue to hold the lock here, it will still be locked until the next unlock() call, causing a possible deadlock with
@@ -161,6 +170,30 @@ static const CGSize kMinReleaseImageOnBackgroundSize = {20.0, 20.0};
   return _defaultImage;
 }
 
+- (void)setCurrentImageQuality:(CGFloat)currentImageQuality
+{
+  ASDN::MutexLocker l(_lock);
+  _currentImageQuality = currentImageQuality;
+}
+
+- (CGFloat)currentImageQuality
+{
+  ASDN::MutexLocker l(_lock);
+  return _currentImageQuality;
+}
+
+- (void)setRenderedImageQuality:(CGFloat)renderedImageQuality
+{
+  ASDN::MutexLocker l(_lock);
+  _renderedImageQuality = renderedImageQuality;
+}
+
+- (CGFloat)renderedImageQuality
+{
+  ASDN::MutexLocker l(_lock);
+  return _renderedImageQuality;
+}
+
 - (void)setDelegate:(id<ASNetworkImageNodeDelegate>)delegate
 {
   ASDN::MutexLocker l(_lock);
@@ -196,6 +229,7 @@ static const CGSize kMinReleaseImageOnBackgroundSize = {20.0, 20.0};
       if (result) {
         self.image = result;
         _imageLoaded = YES;
+        _currentImageQuality = 1.0;
       }
     }
   }
@@ -276,7 +310,7 @@ static const CGSize kMinReleaseImageOnBackgroundSize = {20.0, 20.0};
   ASImageDownloaderProgressImage progress = nil;
   if (ASInterfaceStateIncludesVisible(interfaceState)) {
     __weak __typeof__(self) weakSelf = self;
-    progress = ^(UIImage * _Nonnull progressImage, id _Nullable downloadIdentifier) {
+    progress = ^(UIImage * _Nonnull progressImage, CGFloat progress, id _Nullable downloadIdentifier) {
       __typeof__(self) strongSelf = weakSelf;
       if (strongSelf == nil) {
         return;
@@ -288,6 +322,9 @@ static const CGSize kMinReleaseImageOnBackgroundSize = {20.0, 20.0};
         return;
       }
       strongSelf.image = progressImage;
+      ASPerformBlockOnMainThread(^{
+        strongSelf->_currentImageQuality = progress;
+      });
     };
   }
   [_downloader setProgressImageBlock:progress callbackQueue:dispatch_get_main_queue() withDownloadIdentifier:_downloadIdentifier];
@@ -310,6 +347,9 @@ static const CGSize kMinReleaseImageOnBackgroundSize = {20.0, 20.0};
   self.animatedImage = nil;
   self.image = _defaultImage;
   _imageLoaded = NO;
+  ASPerformBlockOnMainThread(^{
+    _currentImageQuality = 0.0;
+  });
 }
 
 - (void)_cancelImageDownload
@@ -393,6 +433,7 @@ static const CGSize kMinReleaseImageOnBackgroundSize = {20.0, 20.0};
           }
           
           _imageLoaded = YES;
+          self.currentImageQuality = 1.0;
           [_delegate imageNode:self didLoadImage:self.image];
         });
       }
@@ -418,6 +459,7 @@ static const CGSize kMinReleaseImageOnBackgroundSize = {20.0, 20.0};
           } else {
             strongSelf.image = [imageContainer asdk_image];
           }
+          strongSelf->_currentImageQuality = 1.0;
         }
 
         strongSelf->_downloadIdentifier = nil;
@@ -472,13 +514,14 @@ static const CGSize kMinReleaseImageOnBackgroundSize = {20.0, 20.0};
 
 #pragma mark - ASDisplayNode+Subclasses
 
-- (void)asyncdisplaykit_asyncTransactionContainerStateDidChange
+- (void)displayDidFinish
 {
-  if (self.asyncdisplaykit_asyncTransactionContainerState == ASAsyncTransactionContainerStateNoTransactions) {
-    ASDN::MutexLocker l(_lock);
-    if (self.layer.contents != nil && _delegateSupportsImageNodeDidFinishDecoding) {
-      [self.delegate imageNodeDidFinishDecoding:self];
-    }
+  [super displayDidFinish];
+
+  ASDN::MutexLocker l(_lock);
+  if (_delegateSupportsImageNodeDidFinishDecoding && self.layer.contents != nil) {
+    _renderedImageQuality = _currentImageQuality;
+    [self.delegate imageNodeDidFinishDecoding:self];
   }
 }
 

AsyncDisplayKit/Details/ASImageProtocols.h

@@ -63,7 +63,7 @@ typedef void(^ASImageCacherCompletion)(id <ASImageContainerProtocol> _Nullable i
 
 typedef void(^ASImageDownloaderCompletion)(id <ASImageContainerProtocol> _Nullable image, NSError * _Nullable error, id _Nullable downloadIdentifier);
 typedef void(^ASImageDownloaderProgress)(CGFloat progress);
-typedef void(^ASImageDownloaderProgressImage)(UIImage *progressImage, id _Nullable downloadIdentifier);
+typedef void(^ASImageDownloaderProgressImage)(UIImage *progressImage, CGFloat progress, id _Nullable downloadIdentifier);
 
 typedef NS_ENUM(NSUInteger, ASImageDownloaderPriority) {
   ASImageDownloaderPriorityPreload = 0,

AsyncDisplayKit/Details/ASPINRemoteImageDownloader.m

@@ -174,7 +174,7 @@
   if (progressBlock) {
     [[self sharedPINRemoteImageManager] setProgressImageCallback:^(PINRemoteImageManagerResult * _Nonnull result) {
       dispatch_async(callbackQueue, ^{
-        progressBlock(result.image, result.UUID);
+        progressBlock(result.image, result.renderedImageQuality, result.UUID);
       });
     } ofTaskWithUUID:downloadIdentifier];
   } else {