#[repr(C)]pub struct EKObject { /* private fields */ }
EKObject
only.Expand description
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<EKObject> for EKCalendar
Available on crate feature EKCalendar
only.
impl AsRef<EKObject> for EKCalendar
EKCalendar
only.Source§impl AsRef<EKObject> for EKCalendarItem
Available on crate feature EKCalendarItem
only.
impl AsRef<EKObject> for EKCalendarItem
EKCalendarItem
only.Source§impl AsRef<EKObject> for EKParticipant
Available on crate feature EKParticipant
only.
impl AsRef<EKObject> for EKParticipant
EKParticipant
only.Source§impl AsRef<EKObject> for EKRecurrenceRule
Available on crate feature EKRecurrenceRule
only.
impl AsRef<EKObject> for EKRecurrenceRule
EKRecurrenceRule
only.Source§impl AsRef<EKObject> for EKReminder
Available on crate features EKCalendarItem
and EKReminder
only.
impl AsRef<EKObject> for EKReminder
EKCalendarItem
and EKReminder
only.Source§impl AsRef<EKObject> for EKStructuredLocation
Available on crate feature EKStructuredLocation
only.
impl AsRef<EKObject> for EKStructuredLocation
EKStructuredLocation
only.Source§impl Borrow<EKObject> for EKCalendar
Available on crate feature EKCalendar
only.
impl Borrow<EKObject> for EKCalendar
EKCalendar
only.Source§impl Borrow<EKObject> for EKCalendarItem
Available on crate feature EKCalendarItem
only.
impl Borrow<EKObject> for EKCalendarItem
EKCalendarItem
only.Source§impl Borrow<EKObject> for EKEvent
Available on crate features EKCalendarItem
and EKEvent
only.
impl Borrow<EKObject> for EKEvent
EKCalendarItem
and EKEvent
only.Source§impl Borrow<EKObject> for EKParticipant
Available on crate feature EKParticipant
only.
impl Borrow<EKObject> for EKParticipant
EKParticipant
only.Source§impl Borrow<EKObject> for EKRecurrenceRule
Available on crate feature EKRecurrenceRule
only.
impl Borrow<EKObject> for EKRecurrenceRule
EKRecurrenceRule
only.Source§impl Borrow<EKObject> for EKReminder
Available on crate features EKCalendarItem
and EKReminder
only.
impl Borrow<EKObject> for EKReminder
EKCalendarItem
and EKReminder
only.Source§impl Borrow<EKObject> for EKStructuredLocation
Available on crate feature EKStructuredLocation
only.
impl Borrow<EKObject> for EKStructuredLocation
EKStructuredLocation
only.Source§impl ClassType for EKObject
impl ClassType for EKObject
Source§const NAME: &'static str = "EKObject"
const NAME: &'static str = "EKObject"
Source§type ThreadKind = <<EKObject as ClassType>::Super as ClassType>::ThreadKind
type ThreadKind = <<EKObject as ClassType>::Super as ClassType>::ThreadKind
Source§impl NSObjectProtocol for EKObject
impl NSObjectProtocol for EKObject
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