kylefang/react-native
1
0
Fork 0
mirror of https://github.com/zhigang1992/react-native.git synced 2026-04-28 20:25:33 +08:00
Code Issues Packages Projects Releases Wiki Activity

Improved threading for image loader

Browse Source 
Summary: public

The image loader was previously returning on the main thread, which could lead to poor performance due to various call sites doing further image processing (resizing, cropping, etc.) directly in the completion block.

This diff modifies the loader to return on a background thread (the same one used to load the image), and updates the call sites to dispatch to the explicit thread they need.

Reviewed By: javache

Differential Revision: D2549774

fb-gh-sync-id: fed73b7c163fdf67ff65bae72ab1986327e75815
This commit is contained in:
Nick Lockwood
2015-10-20 05:00:50 -07:00
committed by facebook-github-bot-8
parent 77154a7581
commit 1d6d1189f0
9 changed files with 131 additions and 108 deletions
Download Patch File Download Diff File Expand all files Collapse all files

39
Libraries/CameraRoll/RCTAssetsLibraryImageLoader.m
View File

@@ -41,10 +41,15 @@ RCT_EXPORT_MODULE()
- (BOOL)canLoadImageURL:(NSURL *)requestURL
{
return [requestURL.scheme.lowercaseString isEqualToString:@"assets-library"];
return [requestURL.scheme caseInsensitiveCompare:@"assets-library"] == NSOrderedSame;
}
- (RCTImageLoaderCancellationBlock)loadImageForURL:(NSURL *)imageURL size:(CGSize)size scale:(CGFloat)scale resizeMode:(UIViewContentMode)resizeMode progressHandler:(RCTImageLoaderProgressBlock)progressHandler completionHandler:(RCTImageLoaderCompletionBlock)completionHandler
- (RCTImageLoaderCancellationBlock)loadImageForURL:(NSURL *)imageURL
size:(CGSize)size
scale:(CGFloat)scale
resizeMode:(UIViewContentMode)resizeMode
progressHandler:(RCTImageLoaderProgressBlock)progressHandler
completionHandler:(RCTImageLoaderCompletionBlock)completionHandler
{
__block volatile uint32_t cancelled = 0;
@@ -69,7 +74,8 @@ RCT_EXPORT_MODULE()
BOOL useMaximumSize = CGSizeEqualToSize(size, CGSizeZero);
ALAssetRepresentation *representation = [asset defaultRepresentation];
#if RCT_DEV
#if RCT_DEV
CGSize sizeBeingLoaded = size;
if (useMaximumSize) {
CGSize pointSize = representation.dimensions;
@@ -78,7 +84,7 @@ RCT_EXPORT_MODULE()
CGSize screenSize;
if ([[[UIDevice currentDevice] systemVersion] compare:@"8.0" options:NSNumericSearch] == NSOrderedDescending) {
screenSize = UIScreen.mainScreen.nativeBounds.size;
screenSize = [UIScreen mainScreen].nativeBounds.size;
} else {
CGSize mainScreenSize = [UIScreen mainScreen].bounds.size;
CGFloat mainScreenScale = [[UIScreen mainScreen] scale];
@@ -87,9 +93,11 @@ RCT_EXPORT_MODULE()
CGFloat maximumPixelDimension = fmax(screenSize.width, screenSize.height);
if (sizeBeingLoaded.width > maximumPixelDimension || sizeBeingLoaded.height > maximumPixelDimension) {
RCTLogInfo(@"[PERF ASSETS] Loading %@ at size %@, which is larger than screen size %@", representation.filename, NSStringFromCGSize(sizeBeingLoaded), NSStringFromCGSize(screenSize));
RCTLogInfo(@"[PERF ASSETS] Loading %@ at size %@, which is larger than screen size %@",
representation.filename, NSStringFromCGSize(sizeBeingLoaded), NSStringFromCGSize(screenSize));
}
#endif
#endif
UIImage *image;
NSError *error = nil;
@@ -106,8 +114,7 @@ RCT_EXPORT_MODULE()
});
} else {
NSString *errorText = [NSString stringWithFormat:@"Failed to load asset at URL %@ with no error message.", imageURL];
NSError *error = RCTErrorWithMessage(errorText);
completionHandler(error, nil);
completionHandler(RCTErrorWithMessage(errorText), nil);
}
} failureBlock:^(NSError *loadError) {
if (cancelled) {
@@ -115,8 +122,7 @@ RCT_EXPORT_MODULE()
}
NSString *errorText = [NSString stringWithFormat:@"Failed to load asset at URL %@.\niOS Error: %@", imageURL, loadError];
NSError *error = RCTErrorWithMessage(errorText);
completionHandler(error, nil);
completionHandler(RCTErrorWithMessage(errorText), nil);
}];
return ^{
@@ -128,14 +134,9 @@ RCT_EXPORT_MODULE()
@implementation RCTBridge (RCTAssetsLibraryImageLoader)
- (RCTAssetsLibraryImageLoader *)assetsLibraryImageLoader
{
return self.modules[RCTBridgeModuleNameForClass([RCTAssetsLibraryImageLoader class])];
}
- (ALAssetsLibrary *)assetsLibrary
{
return [self.assetsLibraryImageLoader assetsLibrary];
return [self.modules[RCTBridgeModuleNameForClass([RCTAssetsLibraryImageLoader class])] assetsLibrary];
}
@end
@@ -154,7 +155,11 @@ static dispatch_queue_t RCTAssetsLibraryImageLoaderQueue(void)
// Why use a custom scaling method? Greater efficiency, reduced memory overhead:
// http://www.mindsea.com/2012/12/downscaling-huge-alassets-without-fear-of-sigkill
static UIImage *RCTScaledImageForAsset(ALAssetRepresentation *representation, CGSize size, CGFloat scale, UIViewContentMode resizeMode, NSError **error)
static UIImage *RCTScaledImageForAsset(ALAssetRepresentation *representation,
CGSize size,
CGFloat scale,
UIViewContentMode resizeMode,
NSError **error)
{
NSUInteger length = (NSUInteger)representation.size;
NSMutableData *data = [NSMutableData dataWithLength:length];