Struct BAAssetPackManager

Source

pub struct BAAssetPackManager { /* private fields */ }

Available on crate feature BAAssetPackManager only.

Expand description

A class that manages asset packs.

The first time that your code refers to the shared manager, Background Assets considers that your app is opting into automatic system management of your asset packs.

Important: When using the asset-pack manager, make sure that you also adopt the corresponding managed extension protocol. For apps that use Apple hosting, the corresponding protocol is SKDownloaderExtension from StoreKit. For other apps, the corresponding protocol is BAManagedDownloaderExtension. Not adopting the right protocol is a programmer error.

Implementations§

Source §

impl BAAssetPackManager

Source

pub unsafe fn sharedManager() -> Retained<BAAssetPackManager>

The shared asset-pack manager.

Source

pub unsafe fn delegate( &self, ) -> Option<Retained<ProtocolObject<dyn BAManagedAssetPackDownloadDelegate>>>

Available on crate feature BAManagedAssetPackDownloadDelegate only.

An object that receives notifications about events that occur as an asset pack is downloaded.

Source

pub unsafe fn setDelegate( &self, delegate: Option<&ProtocolObject<dyn BAManagedAssetPackDownloadDelegate>>, )

Available on crate feature BAManagedAssetPackDownloadDelegate only.

Setter for delegate.

This is a weak property.

Source

pub unsafe fn init(this: Allocated<Self>) -> Retained<Self>

Source

pub unsafe fn new() -> Retained<Self>

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pub unsafe fn getAllAssetPacksWithCompletionHandler( &self, completion_handler: &DynBlock<dyn Fn(mut NSSet<BAAssetPack>, mut NSError)>, )

Available on crate features BAAssetPack and block2 only.

Gets the asset packs that are available to download.

This method might attempt to get the latest asset-pack information from the server.

Parameter completionHandler: A block that receives the asset packs or an error if one occurs.

Source

pub unsafe fn getAssetPackWithIdentifier_completionHandler( &self, asset_pack_identifier: &NSString, completion_handler: &DynBlock<dyn Fn(mut BAAssetPack, mut NSError)>, )

Available on crate features BAAssetPack and block2 only.

Gets the asset pack with the given identifier.

If no asset pack with the given identifier is found, then the block will receive an NSError object with BAManagedErrorCode/BAManagedErrorCodeAssetPackNotFound as its code for the error parameter. This method might attempt to get the latest asset-pack information from the server.

Parameters:
assetPackIdentifier: The asset pack’s identifier.
completionHandler: A block that receives the asset pack or an error if one occurs.

Source

pub unsafe fn getStatusOfAssetPackWithIdentifier_completionHandler( &self, asset_pack_identifier: &NSString, completion_handler: &DynBlock<dyn Fn(BAAssetPackStatus, *mut NSError)>, )

Available on crate features BAAssetPackStatus and block2 only.

Gets the status of the asset pack with the specified identifier.

If no asset pack with the specified identifier is found, then the block will receive an NSError object with BAManagedErrorCode/BAManagedErrorCodeAssetPackNotFound as its code for the error parameter. This method attempts to get the latest asset-pack information from the server. No updates or removals are automatically triggered.

Parameters:
assetPackIdentifier: The asset pack’s identifier.
completionHandler: A block that receives the status of the asset pack or an error if one occurs.

Source

pub unsafe fn ensureLocalAvailabilityOfAssetPack_completionHandler( &self, asset_pack: &BAAssetPack, completion_handler: &DynBlock<dyn Fn(*mut NSError)>, )

Available on crate features BAAssetPack and block2 only.

Ensures that the specified asset pack be available locally.

This method checks if the asset pack is currently downloaded. If it isn’t, then it schedules it to be downloaded and calls the block with nil for the block’s error parameter when the download completes. It’s guaranteed that the requested asset pack will be available locally once the block is called with nil for its error parameter. If a non-nil value is provided to the block’s error parameter, then the asset pack is not guaranteed to be available locally. You can optionally monitor download progress by attaching a delegate object to delegate.

Parameters:
assetPack: The asset pack the local availability of which to ensure.
completionHandler: A block that’s called when the asset pack is available locally or that receives an error if one occurs.

Source

pub unsafe fn checkForUpdatesWithCompletionHandler( &self, completion_handler: Option<&DynBlock<dyn Fn(mut NSSet<NSString>, mut NSSet<NSString>, *mut NSError)>>, )

Available on crate feature block2 only.

Gets the latest asset-pack information from the server, updates outdated asset packs, and removes obsolete asset packs.

Parameter completionHandler: A block that receives a set of identifiers of asset packs that are being updated and a set of identifiers of removed asset packs or an error if one occurs.

Source

pub unsafe fn contentsAtPath_searchingInAssetPackWithIdentifier_options_error( &self, path: &NSString, asset_pack_identifier: Option<&NSString>, options: NSDataReadingOptions, ) -> Result<Retained<NSData>, Retained<NSError>>

Returns the contents of an asset file at the specified relative path.

All asset packs share the same namespace, so you can treat the overall collection of downloaded asset packs as if it were a single root directory that contains all of your subdirectories and asset files, regardless of the specific asset pack in which any particular file resides. If there’s a file-path collision across multiple asset packs, then it’s undefined from which asset pack the file will be read unless you explicitly limit the search to a particular asset pack by passing a non-nil identifier to the assetPackIdentifier parameter.

Parameters:
path: The relative file path.
assetPackIdentifier: The identifier of the asset pack in which you want to search for the file or nil if you want to search in all asset packs.
options: Options for how to read the contents of the file into a data object.
error: A pointer to an error that will be set if an error occurs. If no file is found at path, then error will point to an NSError object with BAManagedErrorCode/BAManagedErrorCodeFileNotFound as its code.
Returns: The file’s contents.

Source

pub unsafe fn URLForPath_error( &self, path: &NSString, ) -> Result<Retained<NSURL>, Retained<NSError>>

Returns a URL for the specified relative path.

All asset packs share the same namespace, so you can treat the overall collection of downloaded asset packs as if it were a single root directory that contains all of your subdirectories and asset files, regardless of the specific asset pack in which any particular file resides. Unlike BAAssetPackManager/contentsAtPath:searchingInAssetPackWithIdentifier:options:error: and BAAssetPackManager/fileDescriptorForPath:searchingInAssetPackWithIdentifier:error:, this method supports retrieving entire directories—including packages—in which case it merges the corresponding slices of the shared logical directory from all downloaded asset packs that contain such slices. If there’s a file-path collision across multiple asset packs, then it’s undefined from which asset pack an individual file will be resolved.

Parameters:
path: The relative file path.
error: A pointer to an error that will be set if an error occurs.
Warning: Don’t persist the returned URL beyond the lifetime of the current process.
Warning: This method is less efficient than are BAAssetPackManager/contentsAtPath:searchingInAssetPackWithIdentifier:options:error: and BAAssetPackManager/fileDescriptorForPath:searchingInAssetPackWithIdentifier:error:; use those methods instead if you can do so. In particular, this method shouldn’t be used to get the URL to the root of the shared asset-pack namespace. Don’t use this method to block the main thread.
Note: This method will return a well formed URL even if no item exists at the specified relative path in any asset pack, in which case any attempts to get its contents—whether it’s a file or a directory—will fail.

Source

pub unsafe fn removeAssetPackWithIdentifier_completionHandler( &self, asset_pack_identifier: &NSString, completion_handler: Option<&DynBlock<dyn Fn(*mut NSError)>>, )

Available on crate feature block2 only.

Removes the specified asset pack from the device.

Parameters:
assetPackIdentifier: The asset pack’s identifier.
completionHandler: A block that receives an error if one occurs.

Methods from Deref<Target = NSObject>§

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pub fn doesNotRecognizeSelector(&self, sel: Sel) -> !

Handle messages the object doesn’t recognize.

See Apple’s documentation for details.

Methods from Deref<Target = AnyObject>§

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pub fn class(&self) -> &'static AnyClass

Dynamically find the class of this object.

§Panics

May panic if the object is invalid (which may be the case for objects returned from unavailable init/new methods).

§Example

Check that an instance of NSObject has the precise class NSObject.

use objc2::ClassType;
use objc2::runtime::NSObject;

let obj = NSObject::new();
assert_eq!(obj.class(), NSObject::class());

Source

pub unsafe fn get_ivar<T>(&self, name: &str) -> &T
where T: Encode,

👎Deprecated: this is difficult to use correctly, use Ivar::load instead.

Use Ivar::load instead.

§Safety

The object must have an instance variable with the given name, and it must be of type T.

See Ivar::load_ptr for details surrounding this.

Source

pub fn downcast_ref<T>(&self) -> Option<&T>
where T: DowncastTarget,

Attempt to downcast the object to a class of type T.

This is the reference-variant. Use Retained::downcast if you want to convert a retained object to another type.

§Mutable classes

Some classes have immutable and mutable variants, such as NSString and NSMutableString.

When some Objective-C API signature says it gives you an immutable class, it generally expects you to not mutate that, even though it may technically be mutable “under the hood”.

So using this method to convert a NSString to a NSMutableString, while not unsound, is generally frowned upon unless you created the string yourself, or the API explicitly documents the string to be mutable.

See Apple’s documentation on mutability and on isKindOfClass: for more details.

§Generic classes

Objective-C generics are called “lightweight generics”, and that’s because they aren’t exposed in the runtime. This makes it impossible to safely downcast to generic collections, so this is disallowed by this method.

You can, however, safely downcast to generic collections where all the type-parameters are AnyObject.

§Panics

This works internally by calling isKindOfClass:. That means that the object must have the instance method of that name, and an exception will be thrown (if CoreFoundation is linked) or the process will abort if that is not the case. In the vast majority of cases, you don’t need to worry about this, since both root objects NSObject and NSProxy implement this method.

§Examples

Cast an NSString back and forth from NSObject.

use objc2::rc::Retained;
use objc2_foundation::{NSObject, NSString};

let obj: Retained<NSObject> = NSString::new().into_super();
let string = obj.downcast_ref::<NSString>().unwrap();
// Or with `downcast`, if we do not need the object afterwards
let string = obj.downcast::<NSString>().unwrap();

Try (and fail) to cast an NSObject to an NSString.

use objc2_foundation::{NSObject, NSString};

let obj = NSObject::new();
assert!(obj.downcast_ref::<NSString>().is_none());

Try to cast to an array of strings.

use objc2_foundation::{NSArray, NSObject, NSString};

let arr = NSArray::from_retained_slice(&[NSObject::new()]);
// This is invalid and doesn't type check.
let arr = arr.downcast_ref::<NSArray<NSString>>();

This fails to compile, since it would require enumerating over the array to ensure that each element is of the desired type, which is a performance pitfall.

Downcast when processing each element instead.

use objc2_foundation::{NSArray, NSObject, NSString};

let arr = NSArray::from_retained_slice(&[NSObject::new()]);

for elem in arr {
    if let Some(data) = elem.downcast_ref::<NSString>() {
        // handle `data`
    }
}