fix: Fix memory leak on iOS. (DylanVann#433)

It's recommended to never retain the strong reference to self into blocks. Blocks maintain strong references to any captured objects, including self, which means that it’s easy to end up with a strong reference cycle. [skip release]
perrystreetsoftware · Apr 23, 2019 · 70be744 · 70be744
1 parent 84e420c
commit 70be744
Showing 1 changed file with 99 additions and 78 deletions.
diff --git a/ios/FastImage/FFFastImageView.m b/ios/FastImage/FFFastImageView.m
@@ -1,11 +1,17 @@
 #import "FFFastImageView.h"
 
-@implementation FFFastImageView {
- BOOL hasSentOnLoadStart;
- BOOL hasCompleted;
- BOOL hasErrored;
- NSDictionary* onLoadEvent;
-}
+
+@interface FFFastImageView()
+
+@property (nonatomic, assign) BOOL hasSentOnLoadStart;
+@property (nonatomic, assign) BOOL hasCompleted;
+@property (nonatomic, assign) BOOL hasErrored;
+
+@property (nonatomic, strong) NSDictionary* onLoadEvent;
+
+@end
+
+@implementation FFFastImageView
 
 - (id) init {
  self = [super init];
@@ -14,82 +20,95 @@ - (id) init {
  return self;
 }
 
-- (void)setResizeMode:(RCTResizeMode)resizeMode
-{
+- (void)dealloc {
+ [NSNotificationCenter.defaultCenter removeObserver:self];
+}
+
+- (void)setResizeMode:(RCTResizeMode)resizeMode {
  if (_resizeMode != resizeMode) {
  _resizeMode = resizeMode;
  self.contentMode = (UIViewContentMode)resizeMode;
  }
 }
 
-- (void)setOnFastImageLoadEnd:(RCTBubblingEventBlock)onFastImageLoadEnd {
+- (void)setOnFastImageLoadEnd:(RCTDirectEventBlock)onFastImageLoadEnd {
  _onFastImageLoadEnd = onFastImageLoadEnd;
- if (hasCompleted) {
+ if (self.hasCompleted) {
  _onFastImageLoadEnd(@{});
  }
 }
 
-- (void)setOnFastImageLoad:(RCTBubblingEventBlock)onFastImageLoad {
+- (void)setOnFastImageLoad:(RCTDirectEventBlock)onFastImageLoad {
  _onFastImageLoad = onFastImageLoad;
- if (hasCompleted) {
- _onFastImageLoad(onLoadEvent);
+ if (self.hasCompleted) {
+ _onFastImageLoad(self.onLoadEvent);
  }
 }
 
 - (void)setOnFastImageError:(RCTDirectEventBlock)onFastImageError {
  _onFastImageError = onFastImageError;
- if (hasErrored) {
+ if (self.hasErrored) {
  _onFastImageError(@{});
  }
 }
 
-- (void)setOnFastImageLoadStart:(RCTBubblingEventBlock)onFastImageLoadStart {
- if (_source && !hasSentOnLoadStart) {
+- (void)setOnFastImageLoadStart:(RCTDirectEventBlock)onFastImageLoadStart {
+ if (_source && !self.hasSentOnLoadStart) {
  _onFastImageLoadStart = onFastImageLoadStart;
  onFastImageLoadStart(@{});
- hasSentOnLoadStart = YES;
+ self.hasSentOnLoadStart = YES;
  } else {
  _onFastImageLoadStart = onFastImageLoadStart;
- hasSentOnLoadStart = NO;
+ self.hasSentOnLoadStart = NO;
  }
 }
 
 - (void)sendOnLoad:(UIImage *)image {
- onLoadEvent = @{
- @"width":[NSNumber numberWithDouble:image.size.width],
- @"height":[NSNumber numberWithDouble:image.size.height]
- };
- if (_onFastImageLoad) {
- _onFastImageLoad(onLoadEvent);
+ self.onLoadEvent = @{
+ @"width":[NSNumber numberWithDouble:image.size.width],
+ @"height":[NSNumber numberWithDouble:image.size.height]
+ };
+ if (self.onFastImageLoad) {
+ self.onFastImageLoad(self.onLoadEvent);
+ }
+}
+
+- (void)imageDidLoadObserver:(NSNotification *)notification {
+ FFFastImageSource *source = notification.object;
+ if (source != nil && source.url != nil) {
+ [self sd_setImageWithURL:source.url];
  }
 }
 
 - (void)setSource:(FFFastImageSource *)source {
  if (_source != source) {
  _source = source;
 
+ // Attach a observer to refresh other FFFastImageView instance sharing the same source
+ [NSNotificationCenter.defaultCenter addObserver:self selector:@selector(imageDidLoadObserver:) name:source.url.absoluteString object:nil];
+
  // Load base64 images.
  NSString* url = [_source.url absoluteString];
  if (url && [url hasPrefix:@"data:image"]) {
- if (_onFastImageLoadStart) {
- _onFastImageLoadStart(@{});
- hasSentOnLoadStart = YES;
+ if (self.onFastImageLoadStart) {
+ self.onFastImageLoadStart(@{});
+ self.hasSentOnLoadStart = YES;
  } {
- hasSentOnLoadStart = NO;
+ self.hasSentOnLoadStart = NO;
  }
  UIImage *image = [UIImage imageWithData:[NSData dataWithContentsOfURL:_source.url]];
  [self setImage:image];
- if (_onFastImageProgress) {
- _onFastImageProgress(@{
- @"loaded": @(1),
- @"total": @(1)
- });
+ if (self.onFastImageProgress) {
+ self.onFastImageProgress(@{
+  @"loaded": @(1),
+  @"total": @(1)
+  });
  }
- hasCompleted = YES;
+ self.hasCompleted = YES;
  [self sendOnLoad:image];
 
- if (_onFastImageLoadEnd) {
- _onFastImageLoadEnd(@{});
+ if (self.onFastImageLoadEnd) {
+ self.onFastImageLoadEnd(@{});
  }
  return;
  }
@@ -100,8 +119,7 @@ - (void)setSource:(FFFastImageSource *)source {
  }];
 
  // Set priority.
- SDWebImageOptions options = 0;
- options |= SDWebImageRetryFailed;
+ SDWebImageOptions options = SDWebImageRetryFailed;
  switch (_source.priority) {
  case FFFPriorityLow:
  options |= SDWebImageLowPriority;
@@ -125,52 +143,55 @@ - (void)setSource:(FFFastImageSource *)source {
  break;
  }
 
- if (_onFastImageLoadStart) {
- _onFastImageLoadStart(@{});
- hasSentOnLoadStart = YES;
+ if (self.onFastImageLoadStart) {
+ self.onFastImageLoadStart(@{});
+ self.hasSentOnLoadStart = YES;
  } {
- hasSentOnLoadStart = NO;
+ self.hasSentOnLoadStart = NO;
  }
- hasCompleted = NO;
- hasErrored = NO;
+ self.hasCompleted = NO;
+ self.hasErrored = NO;
 
- // Load the new source.
- // This will work for:
- // - https://
- // - file:///var/containers/Bundle/Application/50953EA3-CDA8-4367-A595-DE863A012336/ReactNativeFastImageExample.app/assets/src/images/fields.jpg
- // - file:///var/containers/Bundle/Application/545685CB-777E-4B07-A956-2D25043BC6EE/ReactNativeFastImageExample.app/assets/src/images/plankton.gif
- // - file:///Users/dylan/Library/Developer/CoreSimulator/Devices/61DC182B-3E72-4A18-8908-8A947A63A67F/data/Containers/Data/Application/AFC2A0D2-A1E5-48C1-8447-C42DA9E5299D/Documents/images/E1F1D5FC-88DB-492F-AD33-B35A045D626A.jpg"
- [self sd_setImageWithURL:_source.url
- placeholderImage:nil
- options:options
- progress:^(NSInteger receivedSize, NSInteger expectedSize, NSURL * _Nullable targetURL) {
- if (_onFastImageProgress) {
- _onFastImageProgress(@{
- @"loaded": @(receivedSize),
- @"total": @(expectedSize)
- });
- }
- } completed:^(UIImage * _Nullable image,
- NSError * _Nullable error,
- SDImageCacheType cacheType,
- NSURL * _Nullable imageURL) {
- if (error) {
- hasErrored = YES;
- if (_onFastImageError) {
- _onFastImageError(@{});
- }
- if (_onFastImageLoadEnd) {
- _onFastImageLoadEnd(@{});
+ [self downloadImage:_source options:options];
+ }
+}
+
+- (void)downloadImage:(FFFastImageSource *) source options:(SDWebImageOptions) options {
+ __weak typeof(self) weakSelf = self; // Always use a weak reference to self in blocks
+ [self sd_setImageWithURL:_source.url
+ placeholderImage:nil
+ options:options
+ progress:^(NSInteger receivedSize, NSInteger expectedSize, NSURL * _Nullable targetURL) {
+ if (weakSelf.onFastImageProgress) {
+ weakSelf.onFastImageProgress(@{
+ @"loaded": @(receivedSize),
+ @"total": @(expectedSize)
+ });
+ }
+ } completed:^(UIImage * _Nullable image,
+ NSError * _Nullable error,
+ SDImageCacheType cacheType,
+ NSURL * _Nullable imageURL) {
+ if (error) {
+ weakSelf.hasErrored = YES;
+ if (weakSelf.onFastImageError) {
+ weakSelf.onFastImageError(@{});
  }
- } else {
- hasCompleted = YES;
- [self sendOnLoad:image];
- if (_onFastImageLoadEnd) {
- _onFastImageLoadEnd(@{});
+ if (weakSelf.onFastImageLoadEnd) {
+ weakSelf.onFastImageLoadEnd(@{});
  }
+ } else {
+ weakSelf.hasCompleted = YES;
+ [weakSelf sendOnLoad:image];
+
+ // Alert other FFFastImageView component sharing the same URL
+ [NSNotificationCenter.defaultCenter postNotificationName:source.url.absoluteString object:source];
+
+ if (weakSelf.onFastImageLoadEnd) {
+ weakSelf.onFastImageLoadEnd(@{});
  }
- }];
- }
+ }
+  }];
 }
 
 @end