pub struct AVAssetDownloadStorageManager { /* private fields */ }AVAssetDownloadStorageManager only.Expand description
An AVAssetDownloadStorageManager manages the policy for automatic purging of downloaded AVAssets. The policy is vended as AVAssetDownloadStorageManagementPolicy object.
When a storage management policy needs to be set on an asset, sharedDownloadStorageManager singleton needs to be fetched. The new policy can then be set by using setStorageManagementPolicy and the location of the downloaded asset.
See also Apple’s documentation
Implementations§
Source§impl AVAssetDownloadStorageManager
impl AVAssetDownloadStorageManager
returns singleton instance.
Sourcepub unsafe fn setStorageManagementPolicy_forURL(
&self,
storage_management_policy: &AVAssetDownloadStorageManagementPolicy,
download_storage_url: &NSURL,
)
pub unsafe fn setStorageManagementPolicy_forURL( &self, storage_management_policy: &AVAssetDownloadStorageManagementPolicy, download_storage_url: &NSURL, )
Sets the policy for asset with disk backing at downloadStorageURL.
- Parameter downloadStorageURL: The location of downloaded asset.
Sourcepub unsafe fn storageManagementPolicyForURL(
&self,
download_storage_url: &NSURL,
) -> Option<Retained<AVAssetDownloadStorageManagementPolicy>>
pub unsafe fn storageManagementPolicyForURL( &self, download_storage_url: &NSURL, ) -> Option<Retained<AVAssetDownloadStorageManagementPolicy>>
Returns the storage management policy for asset downloaded at downloadStorageURL. This may be nil if a storageManagementPolicy was never set on the downloaded asset.
- Parameter downloadStorageURL: The location of downloaded asset.
Methods from Deref<Target = NSObject>§
Sourcepub fn doesNotRecognizeSelector(&self, sel: Sel) -> !
pub fn doesNotRecognizeSelector(&self, sel: Sel) -> !
Handle messages the object doesn’t recognize.
See Apple’s documentation for details.
Methods from Deref<Target = AnyObject>§
Sourcepub fn class(&self) -> &'static AnyClass
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());Sourcepub unsafe fn get_ivar<T>(&self, name: &str) -> &Twhere
T: Encode,
👎Deprecated: this is difficult to use correctly, use Ivar::load instead.
pub unsafe fn get_ivar<T>(&self, name: &str) -> &Twhere
T: Encode,
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.
Sourcepub fn downcast_ref<T>(&self) -> Option<&T>where
T: DowncastTarget,
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`
}
}Trait Implementations§
Source§impl ClassType for AVAssetDownloadStorageManager
impl ClassType for AVAssetDownloadStorageManager
Source§const NAME: &'static str = "AVAssetDownloadStorageManager"
const NAME: &'static str = "AVAssetDownloadStorageManager"
Source§type ThreadKind = <<AVAssetDownloadStorageManager as ClassType>::Super as ClassType>::ThreadKind
type ThreadKind = <<AVAssetDownloadStorageManager as ClassType>::Super as ClassType>::ThreadKind
Source§impl Hash for AVAssetDownloadStorageManager
impl Hash for AVAssetDownloadStorageManager
Source§impl NSObjectProtocol for AVAssetDownloadStorageManager
impl NSObjectProtocol for AVAssetDownloadStorageManager
Source§fn isEqual(&self, other: Option<&AnyObject>) -> bool
fn isEqual(&self, other: Option<&AnyObject>) -> bool
Source§fn hash(&self) -> usize
fn hash(&self) -> usize
Source§fn isKindOfClass(&self, cls: &AnyClass) -> bool
fn isKindOfClass(&self, cls: &AnyClass) -> bool
Source§fn is_kind_of<T>(&self) -> bool
fn is_kind_of<T>(&self) -> bool
isKindOfClass directly, or cast your objects with AnyObject::downcast_ref