Merge pull request #590 from rcancro/master

Add expectedSize to ASNetworkImageNode

AsyncDisplayKit/ASDisplayNode.h

@@ -185,6 +185,16 @@ typedef CALayer *(^ASDisplayNodeLayerBlock)();
  */
 @property (nonatomic, readonly, assign) ASSizeRange constrainedSizeForCalculatedLayout;
 
+/**
+ * @abstract Provides a default intrinsic content size for calculateSizeThatFits:. This is useful when laying out
+ * a node that either has no intrinsic content size or should be laid out at a different size than its intrinsic content
+ * size. For example, this property could be set on an ASImageNode to display at a size different from the underlying
+ * image size.
+ *
+ * @return The preferred frame size of this node
+ */
+@property (atomic, assign, readwrite) CGSize preferredFrameSize;
+
 /** @name Managing the nodes hierarchy */
 
 

AsyncDisplayKit/ASDisplayNode.mm

@@ -47,6 +47,7 @@
 @synthesize flexShrink = _flexShrink;
 @synthesize flexBasis = _flexBasis;
 @synthesize alignSelf = _alignSelf;
+@synthesize preferredFrameSize = _preferredFrameSize;
 
 BOOL ASDisplayNodeSubclassOverridesSelector(Class subclass, SEL selector)
 {
@@ -155,6 +156,7 @@ void ASDisplayNodeRespectThreadAffinityOfNode(ASDisplayNode *node, void (^block)
   _methodOverrides = overrides;
 
   _flexBasis = ASRelativeDimensionUnconstrained;
+  _preferredFrameSize = CGSizeZero;
 }
 
 - (id)init
@@ -1350,7 +1352,7 @@ static NSInteger incrementIfFound(NSInteger i) {
 - (CGSize)calculateSizeThatFits:(CGSize)constrainedSize
 {
   ASDisplayNodeAssertThreadAffinity(self);
-  return CGSizeZero;
+  return _preferredFrameSize;
 }
 
 - (ASLayoutSpec *)layoutSpecThatFits:(ASSizeRange)constrainedSize
@@ -1377,6 +1379,17 @@ static NSInteger incrementIfFound(NSInteger i) {
   return _constrainedSize;
 }
 
+- (void)setPreferredFrameSize:(CGSize)preferredFrameSize
+{
+  ASDN::MutexLocker l(_propertyLock);
+  _preferredFrameSize = preferredFrameSize;
+}
+
+- (CGSize)preferredFrameSize
+{
+  ASDN::MutexLocker l(_propertyLock);
+  return _preferredFrameSize;
+}
 - (UIImage *)placeholderImage
 {
   return nil;

AsyncDisplayKit/ASImageNode.mm

@@ -111,7 +111,10 @@
 - (CGSize)calculateSizeThatFits:(CGSize)constrainedSize
 {
   ASDN::MutexLocker l(_imageLock);
-  if (_image)
+  // if a preferredFrameSize is set, call the superclass to return that instead of using the image size.
+  if (CGSizeEqualToSize(self.preferredFrameSize, CGSizeZero) == NO)
+    return [super calculateSizeThatFits:constrainedSize];
+  else if (_image)
     return _image.size;
   else
     return CGSizeZero;