Inherits from NSObject
Conforms to NSCacheDelegate
Declared in YLCache.h
YLCache.m

Overview

YLCache is responsible for all PDF rendering related things. It can render PDF pages into images, load pre-rendered images from disk/memory and save rendered images to memory/disk.

Tasks

Initialization

  • + sharedCache

    Returns a reference to the singleton YLCache instance.

Caching Methods

Delegate Methods

Helper Methods

  • – pauseCaching:

    Use this function to pause rendering/caching operations running in the background. The search operation uses this function to temporarily pause caching while searching for text because it’s a CPU-heavy operation.

  • – resumeCaching:

    Use this function to resume rendering/caching operations running in the background. Operations will only continue when YLCache is not waiting for other services.

  • – clearCache

    This function will clear the memory cache.

  • – clearCacheForDocument:

    This function will remove the cache on disk for a specific document.

Class Methods

sharedCache

Returns a reference to the singleton YLCache instance.

+ (YLCache *)sharedCache

Return Value

An initialized YLCache instance.

Discussion

Returns a reference to the singleton YLCache instance.

Declared In

YLCache.h

Instance Methods

addDelegate:delegateQueue:

Use this function to register yourself as a delegate.

- (void)addDelegate:(id)delegate delegateQueue:(dispatch_queue_t)delegateQueue

Parameters

delegate

Reference to the delegate object.

delegateQueue

The queue on which the delegate should be informed. If you want to get informed on the main thread use dispatch_get_main_queue() here.

Discussion

Use this function to register yourself as a delegate.

Declared In

YLCache.h

cachedImageForDocument:page:size:

Use this function to request a pre-rendered image for a specific PDF page.

- (id)cachedImageForDocument:(YLDocument *)document page:(NSUInteger)page size:(YLPDFImageSize)size

Parameters

document

Reference to the document.

page

Page number starting from 0.

size

Type of image that should be created for this page.

Return Value

A subclass of YLOperation (YLLoadOperation or YLRenderOperation) or an UIImage instance if the image is available in the cache.

Discussion

Use this function to request a pre-rendered image for a specific PDF page.

Declared In

YLCache.h

cancelOperation:

Cancels a load/render operation.

- (void)cancelOperation:(YLOperation *)operation

Parameters

operation

An instance of YLLoadOperation or YLRenderOperation.

Discussion

Cancels a load/render operation.

Declared In

YLCache.h

clearCache

This function will clear the memory cache.

- (void)clearCache

Discussion

This function will clear the memory cache.

Declared In

YLCache.h

clearCacheForDocument:

This function will remove the cache on disk for a specific document.

- (void)clearCacheForDocument:(YLDocument *)document

Parameters

document

Reference to the document.

Discussion

This function will remove the cache on disk for a specific document.

Declared In

YLCache.h

pauseCaching:

Use this function to pause rendering/caching operations running in the background. The search operation uses this function to temporarily pause caching while searching for text because it’s a CPU-heavy operation.

- (void)pauseCaching:(NSString *)caller

Parameters

caller

String value that serves as an identifier. You must use the same identifier when calling resumeCaching!

Discussion

Use this function to pause rendering/caching operations running in the background. The search operation uses this function to temporarily pause caching while searching for text because it’s a CPU-heavy operation.

Declared In

YLCache.h

removeDelegate:

Use this function to unregister yourself as a delegate.

- (void)removeDelegate:(id)delegate

Parameters

delegate

Reference to the delegate object.

Discussion

Use this function to unregister yourself as a delegate.

Declared In

YLCache.h

resumeCaching:

Use this function to resume rendering/caching operations running in the background. Operations will only continue when YLCache is not waiting for other services.

- (void)resumeCaching:(NSString *)caller

Parameters

caller

String value that serves as an identifier. Use the same identifier you used when calling pauseCaching!

Discussion

Use this function to resume rendering/caching operations running in the background. Operations will only continue when YLCache is not waiting for other services.

Declared In

YLCache.h

startCachingDocument:startPage:size:

Starts pre-caching the document in the background.

- (void)startCachingDocument:(YLDocument *)document startPage:(NSUInteger)page size:(YLPDFImageSize)size

Parameters

document

Reference to the document.

page

Page number starting from 0. The document will be parsed starting from this page.

size

This defines the type of images that should be created for this document.

Discussion

Starts pre-caching the document in the background.

Declared In

YLCache.h

stopCachingDocument:

Stops all load/render operations for a specific document.

- (void)stopCachingDocument:(YLDocument *)document

Parameters

document

Reference to the document.

Discussion

Stops all load/render operations for a specific document.

Declared In

YLCache.h