TKImageCache Class Reference

Inherits from	NSCache
Declared in	TKImageCache.h

Overview

An TKImageCache object provides a way to manage images between the network, disk and NSCache.

Tasks

Initializing An Image Cache Object

– init
Initialize a new image cache object.
– initWithCacheDirectoryName:
Initialize a new image cache object.

Properties

shouldNetworkActivity
Shows network activity monitor in status bar when network requests are created.
property
imagesQueue
The queue that manages all network requests for images
property
cacheDirectoryName
The directory where images are stored on disk
property
notificationName
The notification name posted to NSNotificationCenter
property
timeTillRefreshCache
The threshold of time images on disk need to be created before to be read from disk. Otherwise the images will be requested from the network again. The time needs to be greater than zero to for the creation date to be check. Default is -1.
property

Getting an image

– imageForKey:url:queueIfNeeded:
Returns an image if cached or properly routes requests to grab the image from disk or network.
– imageForKey:url:queueIfNeeded:tag:
Returns an image if cached or properly routes requests to grab the image from disk or network.
– cachedImageForKey:
Grabs an image object directly from disk.
– imageExistsWithKey:
Checks to see if an image exists in cache or on disk for the given key.

Managing images and requests.

– cancelOperations
Cancel all image requests
– removeRequestForKey:
Remove an image request for a specific key
– clearCachedImages
Clears local cache and remove all images from disk
– removeCachedImagesFromDiskOlderThanTime:
Remove all images from disk that we’re create earlier than a certain time

For subclassing

– cacheDirectoryPath
The directory where images are stored on disk.
– adjustImageRecieved:
Perform image adjustments before storing it in local cache.

Properties

cacheDirectoryName

The directory where images are stored on disk

@property (nonatomic, copy) NSString *cacheDirectoryName

Discussion

The directory where images are stored on disk

Declared In

TKImageCache.h

imagesQueue

The queue that manages all network requests for images

@property (nonatomic, strong) TKNetworkQueue *imagesQueue

Discussion

The queue that manages all network requests for images

Declared In

TKImageCache.h

notificationName

The notification name posted to NSNotificationCenter

@property (nonatomic, copy) NSString *notificationName

Discussion

The notification name posted to NSNotificationCenter

Declared In

TKImageCache.h

shouldNetworkActivity

Shows network activity monitor in status bar when network requests are created.

@property BOOL shouldNetworkActivity

Discussion

Shows network activity monitor in status bar when network requests are created.

Declared In

TKImageCache.h

timeTillRefreshCache

The threshold of time images on disk need to be created before to be read from disk. Otherwise the images will be requested from the network again. The time needs to be greater than zero to for the creation date to be check. Default is -1.

@property (nonatomic, assign) NSTimeInterval timeTillRefreshCache

Discussion

Declared In

TKImageCache.h

Instance Methods

adjustImageRecieved:

Perform image adjustments before storing it in local cache.

- (UIImage *)adjustImageRecieved:(UIImage *)image

Parameters

image: The image received from disk or the network.

Return Value

The adjusted image.

Discussion

Perform image adjustments before storing it in local cache.

Declared In

TKImageCache.h

cacheDirectoryPath

The directory where images are stored on disk.

- (NSString *)cacheDirectoryPath

Return Value

A NSString with the location to store images.

Discussion

The directory where images are stored on disk.

Declared In

TKImageCache.h

cachedImageForKey:

Grabs an image object directly from disk.

- (UIImage *)cachedImageForKey:(NSString *)key

Parameters

key: The key corresponding to a specific image..

Return Value

Returns an unadjusted UIImage object direct from disk.

Discussion

Grabs an image object directly from disk.

Declared In

TKImageCache.h

cancelOperations

Cancel all image requests

- (void)cancelOperations

Discussion

Cancel all image requests

Declared In

TKImageCache.h

clearCachedImages

Clears local cache and remove all images from disk

- (void)clearCachedImages

Discussion

Clears local cache and remove all images from disk

Declared In

TKImageCache.h

imageExistsWithKey:

Checks to see if an image exists in cache or on disk for the given key.

- (BOOL)imageExistsWithKey:(NSString *)key

Parameters

key: The key corresponding to a specific image.

Return Value

Returns YES is the image corresponding to the key exists on disk or in NSCache, otherwise NO.

Discussion

Checks to see if an image exists in cache or on disk for the given key.

Declared In

TKImageCache.h

imageForKey:url:queueIfNeeded:

Returns an image if cached or properly routes requests to grab the image from disk or network.

- (UIImage *)imageForKey:(NSString *)key url:(NSURL *)url queueIfNeeded:(BOOL)queueIfNeeded

Parameters

key: The key corresponding to a specific image.

url: The URL to grab the image data from the network.

queueIfNeeded: If the image is not on disk or in cache, a network request will be create to grab the image data.

Return Value

Returns an UIImage object if the image is in NSCache.

Discussion

Returns an image if cached or properly routes requests to grab the image from disk or network.

Declared In

TKImageCache.h

imageForKey:url:queueIfNeeded:tag:

Returns an image if cached or properly routes requests to grab the image from disk or network.

- (UIImage *)imageForKey:(NSString *)key url:(NSURL *)url queueIfNeeded:(BOOL)queueIfNeeded tag:(NSUInteger)tag

Parameters

key: The key corresponding to a specific image.

url: The URL to grab the image data from the network.

queueIfNeeded: If the image is not on disk or in cache, a network request will be create to grab the image data.

tag: A tag to associate the image with the rest of your application.

Return Value

Returns an UIImage object if the image is in NSCache.

Discussion

Returns an image if cached or properly routes requests to grab the image from disk or network.

Declared In

TKImageCache.h

init

Initialize a new image cache object.

- (id)init

Return Value

A new created TKImageCache object.

Discussion

Initialize a new image cache object.

Declared In

TKImageCache.h

initWithCacheDirectoryName:

Initialize a new image cache object.

- (id)initWithCacheDirectoryName:(NSString *)cacheDirectoryName

Parameters

cacheDirectoryName: The name of the folder to place cached images to disk.

Return Value

A new created TKImageCache object.

Discussion

Initialize a new image cache object.

Declared In

TKImageCache.h

removeCachedImagesFromDiskOlderThanTime:

Remove all images from disk that we’re create earlier than a certain time

- (void)removeCachedImagesFromDiskOlderThanTime:(NSTimeInterval)time

Parameters

time: The time for which all images files must be created before to remain on disk.

Discussion

Remove all images from disk that we’re create earlier than a certain time

Declared In

TKImageCache.h

removeRequestForKey:

Remove an image request for a specific key

- (void)removeRequestForKey:(NSString *)key

Parameters

key: The key corresponding to a specific image.

Discussion

Remove an image request for a specific key

Declared In

TKImageCache.h