react-native/Libraries/Image/RCTImageLoader.h

197 lines
7.9 KiB
Objective-C

/**
* Copyright (c) 2015-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 <UIKit/UIKit.h>
#import "RCTBridge.h"
#import "RCTURLRequestHandler.h"
#import "RCTResizeMode.h"
@class ALAssetsLibrary;
typedef void (^RCTImageLoaderProgressBlock)(int64_t progress, int64_t total);
typedef void (^RCTImageLoaderCompletionBlock)(NSError *error, UIImage *image);
typedef void (^RCTImageLoaderCancellationBlock)(void);
@interface UIImage (React)
@property (nonatomic, copy) CAKeyframeAnimation *reactKeyframeAnimation;
@end
@interface RCTImageLoader : NSObject <RCTBridgeModule, RCTURLRequestHandler>
/**
* The maximum number of concurrent image loading tasks. Loading and decoding
* images can consume a lot of memory, so setting this to a higher value may
* cause memory to spike. If you are seeing out-of-memory crashes, try reducing
* this value.
*/
@property (nonatomic, assign) NSUInteger maxConcurrentLoadingTasks;
/**
* The maximum number of concurrent image decoding tasks. Decoding large
* images can be especially CPU and memory intensive, so if your are decoding a
* lot of large images in your app, you may wish to adjust this value.
*/
@property (nonatomic, assign) NSUInteger maxConcurrentDecodingTasks;
/**
* Decoding large images can use a lot of memory, and potentially cause the app
* to crash. This value allows you to throttle the amount of memory used by the
* decoder independently of the number of concurrent threads. This means you can
* still decode a lot of small images in parallel, without allowing the decoder
* to try to decompress multiple huge images at once. Note that this value is
* only a hint, and not an indicator of the total memory used by the app.
*/
@property (nonatomic, assign) NSUInteger maxConcurrentDecodingBytes;
/**
* Loads the specified image at the highest available resolution.
* Can be called from any thread, will call back on an unspecified thread.
*/
- (RCTImageLoaderCancellationBlock)loadImageWithTag:(NSString *)imageTag
callback:(RCTImageLoaderCompletionBlock)callback;
/**
* As above, but includes target size, scale and resizeMode, which are used to
* select the optimal dimensions for the loaded image.
*/
- (RCTImageLoaderCancellationBlock)loadImageWithTag:(NSString *)imageTag
size:(CGSize)size
scale:(CGFloat)scale
resizeMode:(RCTResizeMode)resizeMode
progressBlock:(RCTImageLoaderProgressBlock)progressBlock
completionBlock:(RCTImageLoaderCompletionBlock)completionBlock;
/**
* Loads an image without clipping the result to fit - used by RCTImageView.
*/
- (RCTImageLoaderCancellationBlock)loadImageWithoutClipping:(NSString *)imageTag
size:(CGSize)size
scale:(CGFloat)scale
resizeMode:(RCTResizeMode)resizeMode
progressBlock:(RCTImageLoaderProgressBlock)progressBlock
completionBlock:(RCTImageLoaderCompletionBlock)completionBlock;
/**
* Finds an appropriate image decoder and passes the target size, scale and
* resizeMode for optimal image decoding. Can be called from any thread,
* will call callback on an unspecified thread.
*/
- (RCTImageLoaderCancellationBlock)decodeImageData:(NSData *)imageData
size:(CGSize)size
scale:(CGFloat)scale
resizeMode:(RCTResizeMode)resizeMode
completionBlock:(RCTImageLoaderCompletionBlock)completionBlock;
/**
* Decodes an image without clipping the result to fit.
*/
- (RCTImageLoaderCancellationBlock)decodeImageDataWithoutClipping:(NSData *)data
size:(CGSize)size
scale:(CGFloat)scale
resizeMode:(RCTResizeMode)resizeMode
completionBlock:(RCTImageLoaderCompletionBlock)completionBlock;
/**
* Get image size, in pixels. This method will do the least work possible to get
* the information, and won't decode the image if it doesn't have to.
*/
- (RCTImageLoaderCancellationBlock)getImageSize:(NSString *)imageTag
block:(void(^)(NSError *error, CGSize size))completionBlock;
@end
@interface RCTBridge (RCTImageLoader)
/**
* The shared image loader instance
*/
@property (nonatomic, readonly) RCTImageLoader *imageLoader;
@end
/**
* Provides the interface needed to register an image loader. Image data
* loaders are also bridge modules, so should be registered using
* RCT_EXPORT_MODULE().
*/
@protocol RCTImageURLLoader <RCTBridgeModule>
/**
* Indicates whether this data loader is capable of processing the specified
* request URL. Typically the handler would examine the scheme/protocol of the
* URL to determine this.
*/
- (BOOL)canLoadImageURL:(NSURL *)requestURL;
/**
* Send a network request to load the request URL. The method should call the
* progressHandler (if applicable) and the completionHandler when the request
* has finished. The method should also return a cancellation block, if
* applicable.
*/
- (RCTImageLoaderCancellationBlock)loadImageForURL:(NSURL *)imageURL
size:(CGSize)size
scale:(CGFloat)scale
resizeMode:(RCTResizeMode)resizeMode
progressHandler:(RCTImageLoaderProgressBlock)progressHandler
completionHandler:(RCTImageLoaderCompletionBlock)completionHandler;
@optional
/**
* If more than one RCTImageURLLoader responds YES to `-canLoadImageURL:`
* then `loaderPriority` is used to determine which one to use. The loader
* with the highest priority will be selected. Default priority is zero. If
* two or more valid loaders have the same priority, the selection order is
* undefined.
*/
- (float)loaderPriority;
@end
/**
* Provides the interface needed to register an image decoder. Image decoders
* are also bridge modules, so should be registered using RCT_EXPORT_MODULE().
*/
@protocol RCTImageDataDecoder <RCTBridgeModule>
/**
* Indicates whether this handler is capable of decoding the specified data.
* Typically the handler would examine some sort of header data to determine
* this.
*/
- (BOOL)canDecodeImageData:(NSData *)imageData;
/**
* Decode an image from the data object. The method should call the
* completionHandler when the decoding operation has finished. The method
* should also return a cancellation block, if applicable.
*/
- (RCTImageLoaderCancellationBlock)decodeImageData:(NSData *)imageData
size:(CGSize)size
scale:(CGFloat)scale
resizeMode:(RCTResizeMode)resizeMode
completionHandler:(RCTImageLoaderCompletionBlock)completionHandler;
@optional
/**
* If more than one RCTImageDataDecoder responds YES to `-canDecodeImageData:`
* then `decoderPriority` is used to determine which one to use. The decoder
* with the highest priority will be selected. Default priority is zero.
* If two or more valid decoders have the same priority, the selection order is
* undefined.
*/
- (float)decoderPriority;
@end