#[repr(C)]pub struct FSFileSystem { /* private fields */ }
FSFileSystem
only.Expand description
An abstract base class for implementing a full-featured file system.
FSFileSystem
is a full-featured file system, which works with one or more FSResource
instances and presents one or more FSVolume
references to callers.
Implement your app extension by providing a subclass of FSFileSystem
as a delegate object.
Your delegate also needs to implement the FSFileSystemOperations
protocol so that it can probe, load, and unload resources.
Note: The current version of FSKit supports only
FSUnaryFileSystem
, notFSFileSystem
.
See also Apple’s documentation
Implementations§
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 AsRef<AnyObject> for FSFileSystem
impl AsRef<AnyObject> for FSFileSystem
Source§impl AsRef<FSFileSystem> for FSFileSystem
impl AsRef<FSFileSystem> for FSFileSystem
Source§impl AsRef<NSObject> for FSFileSystem
impl AsRef<NSObject> for FSFileSystem
Source§impl Borrow<AnyObject> for FSFileSystem
impl Borrow<AnyObject> for FSFileSystem
Source§impl Borrow<NSObject> for FSFileSystem
impl Borrow<NSObject> for FSFileSystem
Source§impl ClassType for FSFileSystem
impl ClassType for FSFileSystem
Source§const NAME: &'static str = "FSFileSystem"
const NAME: &'static str = "FSFileSystem"
Source§type ThreadKind = <<FSFileSystem as ClassType>::Super as ClassType>::ThreadKind
type ThreadKind = <<FSFileSystem as ClassType>::Super as ClassType>::ThreadKind
Source§impl Debug for FSFileSystem
impl Debug for FSFileSystem
Source§impl Deref for FSFileSystem
impl Deref for FSFileSystem
Source§impl FSFileSystemBase for FSFileSystem
impl FSFileSystemBase for FSFileSystem
Source§unsafe fn containerStatus(&self) -> Retained<FSContainerStatus>
unsafe fn containerStatus(&self) -> Retained<FSContainerStatus>
FSFileSystemBase
and FSContainer
only.Source§unsafe fn setContainerStatus(&self, container_status: &FSContainerStatus)
unsafe fn setContainerStatus(&self, container_status: &FSContainerStatus)
FSFileSystemBase
and FSContainer
only.containerStatus
.Source§unsafe fn wipeResource_completionHandler(
&self,
resource: &FSBlockDeviceResource,
completion: &DynBlock<dyn Fn(*mut NSError)>,
)
unsafe fn wipeResource_completionHandler( &self, resource: &FSBlockDeviceResource, completion: &DynBlock<dyn Fn(*mut NSError)>, )
FSResource
and block2
and FSFileSystemBase
only.Source§impl Hash for FSFileSystem
impl Hash for FSFileSystem
Source§impl Message for FSFileSystem
impl Message for FSFileSystem
Source§impl NSObjectProtocol for FSFileSystem
impl NSObjectProtocol for FSFileSystem
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