#[repr(C)]pub struct UIAlertAction { /* private fields */ }
UIAlertController
only.Expand description
Implementations§
impl UIAlertAction
UIAccessibility.
Source§impl UIAlertAction
impl UIAlertAction
pub unsafe fn actionWithTitle_style_handler( title: Option<&NSString>, style: UIAlertActionStyle, handler: Option<&DynBlock<dyn Fn(NonNull<UIAlertAction>)>>, mtm: MainThreadMarker, ) -> Retained<Self>
block2
only.pub unsafe fn title(&self) -> Option<Retained<NSString>>
pub unsafe fn style(&self) -> UIAlertActionStyle
pub unsafe fn isEnabled(&self) -> bool
Sourcepub unsafe fn setEnabled(&self, enabled: bool)
pub unsafe fn setEnabled(&self, enabled: bool)
Setter for isEnabled
.
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
Available on crate feature UIIndirectScribbleInteraction
only.
pub fn class(&self) -> &'static AnyClass
UIIndirectScribbleInteraction
only.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.Available on crate feature UIIndirectScribbleInteraction
only.
pub unsafe fn get_ivar<T>(&self, name: &str) -> &Twhere
T: Encode,
Ivar::load
instead.UIIndirectScribbleInteraction
only.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,
Available on crate feature UIIndirectScribbleInteraction
only.
pub fn downcast_ref<T>(&self) -> Option<&T>where
T: DowncastTarget,
UIIndirectScribbleInteraction
only.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 UIAlertAction
impl AsRef<AnyObject> for UIAlertAction
Source§impl AsRef<NSObject> for UIAlertAction
impl AsRef<NSObject> for UIAlertAction
Source§impl AsRef<UIAlertAction> for UIAlertAction
impl AsRef<UIAlertAction> for UIAlertAction
Source§impl Borrow<AnyObject> for UIAlertAction
impl Borrow<AnyObject> for UIAlertAction
Source§impl Borrow<NSObject> for UIAlertAction
impl Borrow<NSObject> for UIAlertAction
Source§impl ClassType for UIAlertAction
impl ClassType for UIAlertAction
Source§const NAME: &'static str = "UIAlertAction"
const NAME: &'static str = "UIAlertAction"
Source§type ThreadKind = dyn MainThreadOnly
type ThreadKind = dyn MainThreadOnly
Source§impl CopyingHelper for UIAlertAction
impl CopyingHelper for UIAlertAction
Source§type Result = UIAlertAction
type Result = UIAlertAction
Self
if the type has no
immutable counterpart. Read moreSource§impl Debug for UIAlertAction
impl Debug for UIAlertAction
Source§impl Deref for UIAlertAction
impl Deref for UIAlertAction
Source§impl Hash for UIAlertAction
impl Hash for UIAlertAction
Source§impl Message for UIAlertAction
impl Message for UIAlertAction
Source§impl NSCopying for UIAlertAction
impl NSCopying for UIAlertAction
Source§impl NSObjectProtocol for UIAlertAction
impl NSObjectProtocol for UIAlertAction
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
Source§fn isMemberOfClass(&self, cls: &AnyClass) -> bool
fn isMemberOfClass(&self, cls: &AnyClass) -> bool
Source§fn respondsToSelector(&self, aSelector: Sel) -> bool
fn respondsToSelector(&self, aSelector: Sel) -> bool
Source§fn conformsToProtocol(&self, aProtocol: &AnyProtocol) -> bool
fn conformsToProtocol(&self, aProtocol: &AnyProtocol) -> bool
Source§fn debugDescription(&self) -> Retained<NSObject>
fn debugDescription(&self) -> Retained<NSObject>
Source§impl PartialEq for UIAlertAction
impl PartialEq for UIAlertAction
Source§impl RefEncode for UIAlertAction
impl RefEncode for UIAlertAction
Source§const ENCODING_REF: Encoding = <NSObject as ::objc2::RefEncode>::ENCODING_REF
const ENCODING_REF: Encoding = <NSObject as ::objc2::RefEncode>::ENCODING_REF
Source§impl UIAccessibilityIdentification for UIAlertAction
Available on crate feature UIAccessibilityIdentification
only.
impl UIAccessibilityIdentification for UIAlertAction
UIAccessibilityIdentification
only.impl DowncastTarget for UIAlertAction
impl Eq for UIAlertAction
Auto Trait Implementations§
impl !Freeze for UIAlertAction
impl !RefUnwindSafe for UIAlertAction
impl !Send for UIAlertAction
impl !Sync for UIAlertAction
impl !Unpin for UIAlertAction
impl !UnwindSafe for UIAlertAction
Blanket Implementations§
Source§impl<T> BorrowMut<T> for Twhere
T: ?Sized,
impl<T> BorrowMut<T> for Twhere
T: ?Sized,
Source§fn borrow_mut(&mut self) -> &mut T
fn borrow_mut(&mut self) -> &mut T
Source§impl<'a, T> MainThreadOnly for T
impl<'a, T> MainThreadOnly for T
Source§fn mtm(&self) -> MainThreadMarker
fn mtm(&self) -> MainThreadMarker
MainThreadMarker
from the main-thread-only object. Read more