alassetslibrary_class.pdf ios reference

ALAssetsLibrary Class Reference

Contents

ALAssetsLibrary Class Reference 4Overview 4Tasks 5

Accessing Assets 5Managing Notifications 5Finding Assets 5Enumerating Assets 5Saving Assets 5Managing Asset Groups 6

Class Methods 6authorizationStatus 6disableSharedPhotoStreamsSupport 6

Instance Methods 7addAssetsGroupAlbumWithName:resultBlock:failureBlock: 7assetForURL:resultBlock:failureBlock: 8enumerateGroupsWithTypes:usingBlock:failureBlock: 9groupForURL:resultBlock:failureBlock: 10videoAtPathIsCompatibleWithSavedPhotosAlbum: 11writeImageDataToSavedPhotosAlbum:metadata:completionBlock: 11writeImageToSavedPhotosAlbum:metadata:completionBlock: 12writeImageToSavedPhotosAlbum:orientation:completionBlock: 13writeVideoAtPathToSavedPhotosAlbum:completionBlock: 13

Constants 14ALAssetsGroupType 14Types of Asset 15ALAssetOrientation 16ALAssetsLibraryGroupsEnumerationResultsBlock 17ALAssetsLibraryAssetForURLResultBlock 18ALAssetsLibraryWriteImageCompletionBlock 19ALAssetsLibraryWriteVideoCompletionBlock 19ALAssetsLibraryAccessFailureBlock 20ALAssetsLibraryGroupResultBlock 20ALAuthorizationStatus 21Notification Keys 22

2012-12-13 | Copyright © 2012 Apple Inc. All Rights Reserved.

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Error Domain 22Error Codes 23

Notifications 26ALAssetsLibraryChangedNotification 26

Document Revision History 27


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Contents

Inherits from NSObject

Conforms to NSObject (NSObject)

Framework /System/Library/Frameworks/AssetsLibrary.framework

Availability Available in iOS 4.0 and later.

Declared in ALAssetsLibrary.h

Related sample code AVCam

AVMovieExporter

AVPlayerDemo

MyImagePicker

PhotosByLocation

OverviewAn instance of ALAssetsLibrary provides access to the videos and photos that are under the control of thePhotos application.

The library includes those that are in the Saved Photos album, those coming from iTunes, and those that weredirectly imported into the device. You use it to retrieve the list of all asset groups and to save images andvideos into the Saved Photos album.

You create an instance of ALAssetsLibrary using alloc and init:

ALAssetsLibrary* library = [[ALAssetsLibrary alloc] init];

The lifetimes of objects you get back from a library instance are tied to the lifetime of the library instance.

Many of the methods declared by ALAssetsLibrary take blocks for failure and success as arguments. Thesemethods are all asynchronous because the user may need to be asked to grant access to the data.


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ALAssetsLibrary Class Reference

Tasks

Accessing Assets

+ authorizationStatus (page 6)Returns photo data authorization status for this application.

Managing Notifications

+ disableSharedPhotoStreamsSupport (page 6)Disables shared photo streams notifications and asset retrieval.

Finding Assets

– assetForURL:resultBlock:failureBlock: (page 8)Invokes a given block passing as a parameter an asset identified by a specified file URL.

Enumerating Assets

– enumerateGroupsWithTypes:usingBlock:failureBlock: (page 9)Invokes a given block passing as a parameter each of the asset groups that match the given asset grouptype.

Saving Assets

– writeVideoAtPathToSavedPhotosAlbum:completionBlock: (page 13)Saves a video identified by a given URL to the Saved Photos album.

– videoAtPathIsCompatibleWithSavedPhotosAlbum: (page 11)Returns a Boolean value that indicates whether a video identified by a given URL is compatible with theSaved Photos album.

– writeImageToSavedPhotosAlbum:orientation:completionBlock: (page 13)Saves a given image to the Saved Photos album.

– writeImageDataToSavedPhotosAlbum:metadata:completionBlock: (page 11)Writes given image data and metadata to the Photos Album.

ALAssetsLibrary Class ReferenceTasks


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– writeImageToSavedPhotosAlbum:metadata:completionBlock: (page 12)Writes a given image and metadata to the Photos Album.

Managing Asset Groups

– addAssetsGroupAlbumWithName:resultBlock:failureBlock: (page 7)Adds a new assets group to the library.

– groupForURL:resultBlock:failureBlock: (page 10)Returns an assets group in the result block for a URL previously retrieved from an ALAssetsGroup object.

Class Methods

authorizationStatus

Returns photo data authorization status for this application.

+ (ALAuthorizationStatus)authorizationStatus

Return ValuePhoto data authorization status for this application. For the constants returned, see“ALAuthorizationStatus” (page 21).

DiscussionThis method does not prompt the user for access.

You can use it to detect restricted access and simply hide UI instead of prompting for access.

AvailabilityAvailable in iOS 6.0 and later.

Declared inALAssetsLibrary.h

disableSharedPhotoStreamsSupport

Disables shared photo streams notifications and asset retrieval.

+ (void)disableSharedPhotoStreamsSupport

ALAssetsLibrary Class ReferenceClass Methods


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DiscussionShared photo streams can generate frequent notifications. Use this method to disable support if appropriatefor your app.

Apps compiled against versions of iOS prior to iOS 6.0 do not have support for shared photo streams.



Instance Methods

addAssetsGroupAlbumWithName:resultBlock:failureBlock:

Adds a new assets group to the library.

- (void)addAssetsGroupAlbumWithName:(NSString *)nameresultBlock:(ALAssetsLibraryGroupResultBlock)resultBlockfailureBlock:(ALAssetsLibraryAccessFailureBlock)failureBlock

Parametersname

The name for the new group.

If name conflicts with another assets group with the same name, then the group is not created andresultBlock returns a nil group.

resultBlockThe block invoked after the add operation completes.

For a description of the block, see ALAssetsLibraryAccessFailureBlock (page 20).

failureBlockThe block to invoke if the add operation fails—for example, if the user denies access to the application.

For a description of the block, see ALAssetsGroupFaces (page 15).

DiscussionThe name of the new asset group is name, its type is ALAssetsGroupAlbum (page 15), and the editableproperty is YES.

ALAssetsLibrary Class ReferenceInstance Methods


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This method is asynchronous. When the assets group is added, the user may be asked to confirm the application’saccess to the data; the method, though, returns immediately. You should perform whatever work you wantwith the group in resultBlock.

If the user denies access to the application, or if no application is allowed to access the data, or if the data iscurrently unavailable, the failure block is called.



assetForURL:resultBlock:failureBlock:

Invokes a given block passing as a parameter an asset identified by a specified file URL.

- (void)assetForURL:(NSURL *)assetURLresultBlock:(ALAssetsLibraryAssetForURLResultBlock)resultBlockfailureBlock:(ALAssetsLibraryAccessFailureBlock)failureBlock

ParametersassetURL

An asset URL previously retrieved from an ALAsset object.

resultBlockThe block to invoke using the asset identified by assetURL.

For a description of the block, see ALAssetsLibraryAssetForURLResultBlock (page 18).

failureBlockThe block to invoke if the user denies access to the assets library.


DiscussionThis method is asynchronous. When the asset is requested, the user may be asked to confirm the application'saccess to the library; the method, though, returns immediately. You should perform whatever work you wantwith the asset in resultBlock.

If the user denies access to the application, or if no application is allowed to access the data, the failure blockis called.




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Related Sample CodePrintPhoto


enumerateGroupsWithTypes:usingBlock:failureBlock:

Invokes a given block passing as a parameter each of the asset groups that match the given asset group type.

- (void)enumerateGroupsWithTypes:(ALAssetsGroupType)typesusingBlock:(ALAssetsLibraryGroupsEnumerationResultsBlock)enumerationBlockfailureBlock:(ALAssetsLibraryAccessFailureBlock)failureBlock

Parameterstypes

The types of asset group over which to enumerate.

The value is a bitfield; you can OR together values fromwriteImageDataToSavedPhotosAlbum:metadata:completionBlock: (page 11).

enumerationBlockThe block to invoke using each asset group in turn.

When the enumeration is done, enumerationBlock is invoked with group set to nil.

For a description of the block, see ALAssetsLibraryGroupsEnumerationResultsBlock (page 17).

failureBlockThe block to invoke if the user denies access to the assets library.


DiscussionThe results are passed one by one to the caller by executing the enumeration block.

This method is asynchronous. When groups are enumerated, the user may be asked to confirm the application'saccess to the data; the method, though, returns immediately. You should perform whatever work you wantwith the assets in enumerationBlock.

If the user denies access to the application, or if no application is allowed to access the data, the failureBlockis called.

Special ConsiderationsThis method will fail with error ALAssetsLibraryAccessGloballyDeniedError (page 25) if the user has notenabled Location Services (in Settings > General).



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Related Sample CodeAVMovieExporterAVPlayerDemoMTAudioProcessingTap Audio Processor


groupForURL:resultBlock:failureBlock:

Returns an assets group in the result block for a URL previously retrieved from an ALAssetsGroup object.

- (void)groupForURL:(NSURL *)groupURLresultBlock:(ALAssetsLibraryGroupResultBlock)resultBlockfailureBlock:(ALAssetsLibraryAccessFailureBlock)failureBlock

ParametersgroupURL

The URL for an ALAssetsGroup object.

resultBlockThe block invoked after the access operation completes.


failureBlockThe block to invoke if the access operation fails—for example, if the user denies access to the application.

For a description of the block, see ALAssetsGroupFaces (page 15).

DiscussionThis method is asynchronous: it returns immediately. You should perform whatever work you want with theassets group in resultBlock.

This method is asynchronous. When the assets group is requested, the user may be asked to confirm theapplication’s access to the data; the method, though, returns immediately. You should perform whatever workyou want with the asset group in resultBlock.

If the user denies access to the application, or if no application is allowed to access the data, or if the data iscurrently unavailable, the failure block is called.



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videoAtPathIsCompatibleWithSavedPhotosAlbum:

Returns a Boolean value that indicates whether a video identified by a given URL is compatible with the SavedPhotos album.

- (BOOL)videoAtPathIsCompatibleWithSavedPhotosAlbum:(NSURL *)videoPathURL

ParametersvideoPathURL

An URL that points to a video file.

Return ValueYES if the video identified by videoPathURL is compatible with the Saved Photos album, otherwise NO.

DiscussionThis method returns the same value as UIVideoAtPathIsCompatibleWithSavedPhotosAlbum would forthe same URL.


See Also– writeVideoAtPathToSavedPhotosAlbum:completionBlock: (page 13)


writeImageDataToSavedPhotosAlbum:metadata:completionBlock:

Writes given image data and metadata to the Photos Album.

- (void)writeImageDataToSavedPhotosAlbum:(NSData *)imageData metadata:(NSDictionary*)metadata completionBlock:(ALAssetsLibraryWriteImageCompletionBlock)completionBlock

ParametersimageData

Data for the image to add to the album.



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metadataThe metadata to associate with the image.

completionBlockThe block invoked after the save operation completes.

For a description of the block, see ALAssetsLibraryWriteImageCompletionBlock (page 19).

DiscussionIf there is a conflict between the metadata in the image data and the metadata dictionary, the image datametadata values will be overwritten.


Related Sample CodeSquareCam


writeImageToSavedPhotosAlbum:metadata:completionBlock:

Writes a given image and metadata to the Photos Album.

- (void)writeImageToSavedPhotosAlbum:(CGImageRef)imageRef metadata:(NSDictionary*)metadata completionBlock:(ALAssetsLibraryWriteImageCompletionBlock)completionBlock

ParametersimageRef

The image to add to the album.

metadataThe metadata to associate with the image.



DiscussionYou must specify the orientation key in the metadata dictionary to preserve the orientation of the image.




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writeImageToSavedPhotosAlbum:orientation:completionBlock:

Saves a given image to the Saved Photos album.

- (void)writeImageToSavedPhotosAlbum:(CGImageRef)imageReforientation:(ALAssetOrientation)orientationcompletionBlock:(ALAssetsLibraryWriteImageCompletionBlock)completionBlock

ParametersimageRef

The image to save to the Saved Photos album.

orientationThe orientation at which to save the image.



DiscussionIf you want to save a UIImage object, you can use the UIImage method CGImage to get a CGImageRef, andcast the image’s imageOrientation to ALAssetOrientation.


See Also– writeVideoAtPathToSavedPhotosAlbum:completionBlock: (page 13)


writeVideoAtPathToSavedPhotosAlbum:completionBlock:

Saves a video identified by a given URL to the Saved Photos album.

- (void)writeVideoAtPathToSavedPhotosAlbum:(NSURL *)videoPathURLcompletionBlock:(ALAssetsLibraryWriteVideoCompletionBlock)completionBlock



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ParametersvideoPathURL

An URL that points to a video file.


For a description of the block, see ALAssetsLibraryWriteVideoCompletionBlock (page 19).

Discussion


See Also– videoAtPathIsCompatibleWithSavedPhotosAlbum: (page 11)– writeImageToSavedPhotosAlbum:orientation:completionBlock: (page 13)

Related Sample CodeAVCamAVMovieExporterAVSimpleEditoriOSRosyWriterStopNGo for iOS


Constants

ALAssetsGroupType

A bitfield to identify types of asset.

typedef NSUInteger ALAssetsGroupType;

DiscussionFor possible values, see “Types of Asset” (page 15).


ALAssetsLibrary Class ReferenceConstants


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Types of Asset

Constants to identify types of asset.

enum {ALAssetsGroupLibrary = (1 << 0),ALAssetsGroupAlbum = (1 << 1),ALAssetsGroupEvent = (1 << 2),ALAssetsGroupFaces = (1 << 3),ALAssetsGroupSavedPhotos = (1 << 4),ALAssetsGroupPhotoStream = (1 << 5),ALAssetsGroupAll = 0xFFFFFFFF,

};

ConstantsALAssetsGroupLibrary

The Library group that includes all assets that are synced from iTunes.

Available in iOS 4.0 and later.

Declared in ALAssetsLibrary.h.

ALAssetsGroupAlbumAll the albums created on the device or synced from iTunes, not including Photo Stream or Shared Streams



ALAssetsGroupEventAll events, including those created during Camera Connection Kit import.



ALAssetsGroupFacesAll the faces albums synced from iTunes.



ALAssetsGroupSavedPhotosAll the photos in the Camera Roll.





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ALAssetsGroupPhotoStreamThe PhotoStream album.

In iOS 6.0 and later, this also includes Shared Streams.



ALAssetsGroupAllThe same as ORing together all the group types except for ALAssetsGroupLibrary.



ALAssetOrientation

Constants to indicate the orientation of an asset.

typedef enum {ALAssetOrientationUp,ALAssetOrientationDown,ALAssetOrientationLeft,ALAssetOrientationRight,ALAssetOrientationUpMirrored,ALAssetOrientationDownMirrored,ALAssetOrientationLeftMirrored,ALAssetOrientationRightMirrored,

} ALAssetOrientation;

ConstantsALAssetOrientationUp

Indicates that the picture is in its default orientation, as shown here.



ALAssetOrientationDownIndicates that the picture has been rotated through 180 degrees with respect to

ALAssetOrientationUp (page 16), as shown here.





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ALAssetOrientationLeftIndicates that the picture has been rotated through 90 degrees counter-clockwise with respect to




ALAssetOrientationRightIndicates that the picture has been rotated through 90 degrees clockwise with respect to




ALAssetOrientationUpMirroredIndicates that the picture has been flipped horizontally with respect to ALAssetOrientationUp (page

16), as shown here.



ALAssetOrientationDownMirroredIndicates that the picture has been rotated through 180 degrees with respect to

ALAssetOrientationUp (page 16) and then flipped horizontally, as shown here.



ALAssetOrientationLeftMirroredIndicates that the picture has been rotated through 90 degrees counter-clockwise with respect to

ALAssetOrientationUp (page 16) and then flipped vertically, as shown here.



ALAssetOrientationRightMirroredIndicates that the picture has been rotated through 90 degrees clockwise with respect to

ALAssetOrientationUp (page 16) and then flipped vertically, as shown here.



ALAssetsLibraryGroupsEnumerationResultsBlock

Signature for the block executed when a match is found during enumeration usingenumerateGroupsWithTypes:usingBlock:failureBlock: (page 9).



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typedef void (^ALAssetsLibraryGroupsEnumerationResultsBlock)(ALAssetsGroup *group, BOOL*stop);

DiscussionThe block parameters are defined as follows:

groupThe current asset group in the enumeration.

stopA pointer to a boolean value; set the value to YES to stop enumeration.



ALAssetsLibraryAssetForURLResultBlock

Signature for the block executed if the user has granted access to the caller to access the data managed by theframework in assetForURL:resultBlock:failureBlock: (page 8).

typedef void (^ALAssetsLibraryAssetForURLResultBlock)(ALAsset *asset);

DiscussionThe block parameter is defined as follows:

assetThe asset identified by the URL parameter in assetForURL:resultBlock:failureBlock: (page 8).

If the asset is not found, asset is nil.





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ALAssetsLibraryWriteImageCompletionBlock

SignaturefortheblockexecutedwhenwriteImageToSavedPhotosAlbum:orientation:completionBlock: (page13) completes.

typedef void (^ALAssetsLibraryWriteImageCompletionBlock)(NSURL *assetURL, NSError *error);


assetURLAn URL that identifies the saved image file.

If the image is not saved, assetURL is nil.

errorIf the image is not saved, an error object that describes the reason for failure, otherwise nil.



ALAssetsLibraryWriteVideoCompletionBlock

Signature for the block executed when writeVideoAtPathToSavedPhotosAlbum:completionBlock: (page13) completes.

typedef void (^ALAssetsLibraryWriteVideoCompletionBlock)(NSURL *assetURL, NSError *error);


assetURLAn URL that identifies the saved video file.

If the video is not saved, assetURL is nil.

errorIf the video is not saved, an error object that describes the reason for failure, otherwise nil.




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ALAssetsLibraryAccessFailureBlock

Signature for the block executed if the user does not grant access to the caller to access the data managed by theframework.

typedef void (^ALAssetsLibraryAccessFailureBlock)(NSError *error);


errorAn error object that describes why access to the library failed.

This block type is used by assetForURL:resultBlock:failureBlock: (page 8) andenumerateGroupsWithTypes:usingBlock:failureBlock: (page 9).



ALAssetsLibraryGroupResultBlock

Signature for the block executed if the user grants access to the caller to access the data managed by theframework..

typedef void (^ALAssetsLibraryGroupResultBlock)(ALAssetsGroup *group));


groupThe group that was added to the assets library.

If the group is not found or not created (for example, because of a name collision), group is nil.



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This block type is used by addAssetsGroupAlbumWithName:resultBlock:failureBlock: (page 7) andgroupForURL:resultBlock:failureBlock: (page 10).



ALAuthorizationStatus

Constants to indicate authorization status.

typedef NS_ENUM(NSInteger,ALAuthorizationStatus) {ALAuthorizationStatusNotDetermined = 0,ALAuthorizationStatusRestricted,ALAuthorizationStatusDenied,ALAuthorizationStatusAuthorized };

ConstantsALAuthorizationStatusNotDetermined

User has not yet made a choice with regards to this application.



ALAuthorizationStatusRestrictedThis application is not authorized to access photo data.

The user cannot change this application’s status, possibly due to active restrictions such as parentalcontrols being in place.



ALAuthorizationStatusDeniedUser has explicitly denied this application access to photos data.



ALAuthorizationStatusAuthorizedUser has authorized this application to access photos data.





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Notification Keys

KeysusedtogetvaluesfromtheuserinformationdictionaryoftheALAssetsLibraryChangedNotification (page26) notification.

NSString * const ALAssetLibraryUpdatedAssetsKey;NSString * const ALAssetLibraryInsertedAssetGroupsKey;NSString * const ALAssetLibraryUpdatedAssetGroupsKey;NSString * const ALAssetLibraryDeletedAssetGroupsKey;

ConstantsALAssetLibraryUpdatedAssetsKey

Value is a set of NSURL objects identifying the assets that were updated.



ALAssetLibraryInsertedAssetGroupsKeyValue is a set of NSURL objects identifying the assets that were inserted.



ALAssetLibraryUpdatedAssetGroupsKeyValue is a set of NSURL objects identifying the asset groups that were updated.



ALAssetLibraryDeletedAssetGroupsKeyValue is a set of NSURL objects identifying the asset groups that were deleted.



DiscussionAssets that are modified use the ALAssetLibraryUpdatedAssetsKey key. Assets that are inserted or deleteduse the ALAssetLibraryUpdatedAssetGroupsKey key for the asset group that contains the asset.

Assets and asset groups that have no strong references are omitted from the notification’s user informationdictionary.

Error Domain

Constant for the AssetsLibrary domain.



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NSString *const ALAssetsLibraryErrorDomain;

ConstantsALAssetsLibraryErrorDomain

Constant used by NSError to distinguish errors belonging to the AssetsLibrary domain.



Error Codes

AssetsLibrary-related error codes

enum {ALAssetsLibraryUnknownError = -1,

ALAssetsLibraryWriteFailedError = -3300,ALAssetsLibraryWriteBusyError = -3301,ALAssetsLibraryWriteInvalidDataError = -3302,ALAssetsLibraryWriteIncompatibleDataError = -3303,ALAssetsLibraryWriteDataEncodingError = -3304,ALAssetsLibraryWriteDiskSpaceError = -3305,

ALAssetsLibraryDataUnavailableError = -3310,

ALAssetsLibraryAccessUserDeniedError = -3311,ALAssetsLibraryAccessGloballyDeniedError = -3312,

};

ConstantsALAssetsLibraryUnknownError

The reason for the error is unknown.



ALAssetsLibraryWriteFailedErrorThe attempt to write data failed.

This error may be returned in the completion block forwriteVideoAtPathToSavedPhotosAlbum:completionBlock: (page 13) andwriteImageToSavedPhotosAlbum:orientation:completionBlock: (page 13) as well as the completionselector for UIImageWriteToSavedPhotosAlbum and UISaveVideoAtPathToSavedPhotosAlbum.





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ALAssetsLibraryWriteBusyErrorWriting was already busy when the attempt to write was made.

You should attempt the write again.




ALAssetsLibraryWriteInvalidDataErrorThe data was invalid.




ALAssetsLibraryWriteIncompatibleDataErrorThe data contained incompatible data.




ALAssetsLibraryWriteDataEncodingErrorThe data contained data with the wrong encoding.






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ALAssetsLibraryWriteDiskSpaceErrorThere was not enough space on the disk to write the data.




ALAssetsLibraryDataUnavailableErrorThe data was not available.

This error may be returned in the ALAssetsLibraryAccessFailureBlock (page 20) forenumerateGroupsWithTypes:usingBlock:failureBlock: (page 9) andassetForURL:resultBlock:failureBlock: (page 8); and in the completion blocks forwriteImageToSavedPhotosAlbum:orientation:completionBlock: (page 13) andwriteImageToSavedPhotosAlbum:orientation:completionBlock: (page 13); as well as in the completionselector for UIImageWriteToSavedPhotosAlbum and UISaveVideoAtPathToSavedPhotosAlbum.



ALAssetsLibraryAccessUserDeniedErrorThe user denied access to the library.

This error may be returned in the ALAssetsLibraryAccessFailureBlock (page 20) block forenumerateGroupsWithTypes:usingBlock:failureBlock: (page 9) andassetForURL:resultBlock:failureBlock: (page 8).



ALAssetsLibraryAccessGloballyDeniedErrorAccess to the library was denied globally.

This error may be returned in the ALAssetsLibraryAccessFailureBlock (page 20) block forenumerateGroupsWithTypes:usingBlock:failureBlock: (page 9) andassetForURL:resultBlock:failureBlock: (page 8).





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Notifications

ALAssetsLibraryChangedNotification

Sent when the contents of the assets library have changed from under the app that is using the data.

In iOS 4.0, the notification’s object is nil. In iOS 4.1 and later, the notification object is the library object thatposted the notification.

In iOS 6.0 and later, the user information dictionary describes what changed: ● If the user information dictionary is nil, reload all assets and asset groups.

● If the user information dictionary an empty dictionary, there is no need to reload assets and asset groups.

● If the user information dictionary is not empty, reload the effected assets and asset groups. For the keysused, see “Notification Keys” (page 22).

This notification is sent on an arbitrary thread.



ALAssetsLibrary Class ReferenceNotifications


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This table describes the changes to ALAssetsLibrary Class Reference .

NotesDate

Added to the discussion of ALAssetsLibraryAccessGloballyDeniedError.2012-12-13

Updated with API to support data privacy.2012-09-19

Updated for iOS v5.0.2011-10-12

Noted that enumerateGroupsWithTypes:usingBlock:failureBlock: fails ifthe user has not enabled Location Services.

2011-04-28

Updated for iOS v4.2010-07-01

First version of a document that describes the object that represents thevideos and photos in the Photos application.

2010-05-24


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Document Revision History

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alassetslibrary_class.pdf ios reference

Documents

assets assetforurl

asset groups

library instance

asset retrieval

types of asset

given asset grouptype

instance methods

class methods