AGSItemResourceCache Class Reference

Description

Information on resources associated with an item.

Instances of this class provide information on resources associated with an item. For instance, an item representing a vector tile layer has style resources such as fonts, sprites, etc.

Since

100.2

Inheritance diagram for AGSItemResourceCache:

Instance Methods
(void)	- cancelLoad
(void)	- doCancelLoading
(void)	- doStartLoading:
(instancetype)	- initWithFileURL:
(void)	- loadDidFinishWithError:
(void)	- loadWithCompletion:
(void)	- onLoadStatusChanged
(void)	- retryLoadWithCompletion:

Class Methods
(instancetype)	+ itemResourceCacheWithFileURL:

Properties
NSURL *	fileURL
AGSLocalItem *	item
NSError *	loadError
AGSLoadStatus	loadStatus

Method Documentation

cancelLoad

- (void) cancelLoad

requiredinherited

Cancels loading if it is in progress, otherwise it does nothing. This should be called carefully because other objects could be waiting for loadWithCompletion: or retryLoadWithCompletion: to complete and this will call them all back with the error of NSUserCancelledError

Since

100

doCancelLoading

- (void) doCancelLoading

Never call this method directly. The framework calls this method on a background thread when cancelLoad (AGSLoadable-p) is called. It is meant to be overriden by subclasses. Subclasses should override this method to cancel loading their data and call loadDidFinishWithError: (AGSLoadableBase(ForSubclassEyesOnly)) at the end passing in an error representing NSUserCancelledError.

Since

100

Provided by category AGSLoadableBase(ForSubclassEyesOnly).

doStartLoading:

- (void) doStartLoading:

(BOOL)

retrying

Never call this method directly. The framework calls this method on a background thread when loadWithCompletion: (AGSLoadable-p) or retryLoadWithCompletion: (AGSLoadable-p) is called. It is meant to be overriden by subclasses. Subclasses should override this method to load their data and call loadDidFinishWithError: (AGSLoadableBase(ForSubclassEyesOnly)) upon completion, passing in the error if any.

Parameters

retrying

flag that is true if this method was called from retryLoadWithCompletion: (AGSLoadable-p).

Since

100

Provided by category AGSLoadableBase(ForSubclassEyesOnly).

initWithFileURL:

- (instancetype) initWithFileURL:

(NSURL *)

fileURL

Initialize this object with a path to the resource cache on disk

Parameters

fileURL

to a directory representing the resource cache on disk

Returns

Initialized item resource cache

Since

100.2

itemResourceCacheWithFileURL:

+ (instancetype) itemResourceCacheWithFileURL:

(NSURL *)

fileURL

Initialize this object with a path to the resource cache on disk

Parameters

fileURL

to a directory representing the resource cache on disk

Returns

Initialized item resource cache

Since

100.2

loadDidFinishWithError:

- (void) loadDidFinishWithError:

(nullable NSError *)

error

Only subclasses should call this method in doStartLoading: (AGSLoadableBase(ForSubclassEyesOnly)) and doCancelLoading (AGSLoadableBase(ForSubclassEyesOnly)) when done loading or failed to load.

Since

100

Provided by category AGSLoadableBase(ForSubclassEyesOnly).

loadWithCompletion:

- (void) loadWithCompletion: (nullable void(^)(NSError *__nullable error))  completion

requiredinherited

Loads data for the object asynchronously. The completion block is invoked upon completion.

You can call this method any number of times, however only one attempt is made to load the data. If it is already loading, it will just continue to load (i.e. not force a reload). If it has already loaded successfully, the completion block will be invoked right away. If it has already failed to load, the completion block will be invoked right away with error previously encountered. This method supports multiple callers and will call them all back on completion. However, each caller's completion block will be invoked once and only once.

Parameters

completion

block that is invoked when object loads successfully or fails to load. An error is passed to the block if the object fails to load.

Note

The completion block is always invoked on the main thread.

Since

100

See also

- cancelLoad to cancel loading

- retryLoadWithCompletion: to force reload

onLoadStatusChanged

- (void) onLoadStatusChanged

Never call this method directly. The framework calls this method on a background thread when AGSLoadable::loadStatus changes is called. Subclasses can optionally implement this to know when their loading status has changed.

Since

100

Provided by category AGSLoadableBase(ForSubclassEyesOnly).

retryLoadWithCompletion:

- (void) retryLoadWithCompletion: (nullable void(^)(NSError *__nullable error))  completion

requiredinherited

Tries to reload when an object has failed to load. This method should be called judiciously. It should be called when:

1. you didn't have network connectivity earlier when it failed and you want to retry now that you have connectivity
2. the server was down earlier when it failed and you want to retry
3. the request is taking too long and you want to cancel it and retry, in which case you will first call cancelLoad and then this method

If the data hasn't started loading, it will start loading. If it is already loading, it will just continue to load. If it has already loaded successfully, calls back right away. If it has already failed to load, tries again. This method supports multiple callers and will call them all back on completion. However, each caller's completion block will be invoked once and only once.

Parameters

completion

block that is invoked when object loads successfully or fails to load. An error is passed to the block if the object fails to load.

Note

The completion block is always invoked on the main thread.

Since

100

Property Documentation

fileURL

- (NSURL*) fileURL

readnonatomicstrong

The path to the on-disk location containing the AGSItemResourceCache. The path can be a directory on-disk that contains the AGSItemResourceCache. Alternatively, if the AGSItemResourceCache was loaded from a package file, such as an AGSMobileMapPackage, the path is to the package.

Since

100.2

item

- (AGSLocalItem*) item

readnonatomicstrong

The AGSLocalItem containing the AGSItemResourceCache's thumbnail and metadata. This property can be nil if the AGSLocalItem is not present within the AGSItemResourceCache directory. If the AGSItemResourceCache was taken offline using AGSExportVectorTilesTask or AGSOfflineMapTask the AGSLocalItem will be populated from the online AGSPortalItem. If the AGSItemResourceCache was created inside an AGSMobileMapPackage authored from ArcGIS Pro then this property will return nil.

Since

100.2

loadError

- (NSError*) loadError

readnonatomicstronginherited

The error that was encountered during the most recent load operation. Will be nil if the operation succeeded.

Since

100

loadStatus

- (AGSLoadStatus) loadStatus

readrequirednonatomicassigninherited

Status of the load operation.

Since

100