Struct UITraitCollection 

pub struct UITraitCollection { /* private fields */ }

Available on crate feature UITraitCollection only.

A trait collection encapsulates the system traits of an interface’s environment.

See also Apple’s documentation

Implementations

impl UITraitCollection

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

pub unsafe fn initWithCoder( this: Allocated<Self>, coder: &NSCoder, ) -> Option<Retained<Self>>

Safety

coder possibly has further requirements.

pub fn containsTraitsInCollection( &self, trait: Option<&UITraitCollection>, ) -> bool

👎Deprecated: Compare values for specific traits in the trait collections instead

pub fn traitCollectionWithTraitsFromCollections( trait_collections: &NSArray<UITraitCollection>, ) -> Retained<UITraitCollection>

👎Deprecated: Use +[UITraitCollection traitCollectionWithTraits:] and -[UITraitCollection traitCollectionByModifyingTraits:] to create and modify trait collections

pub fn traitCollectionWithUserInterfaceIdiom( idiom: UIUserInterfaceIdiom, ) -> Retained<UITraitCollection>

Available on crate feature UIDevice only.

pub unsafe fn userInterfaceIdiom(&self) -> UIUserInterfaceIdiom

Available on crate feature UIDevice only.

This property is not atomic.

Safety

This might not be thread-safe.

pub fn traitCollectionWithUserInterfaceStyle( user_interface_style: UIUserInterfaceStyle, ) -> Retained<UITraitCollection>

Available on crate feature UIInterface only.

pub unsafe fn userInterfaceStyle(&self) -> UIUserInterfaceStyle

Available on crate feature UIInterface only.

This property is not atomic.

Safety

This might not be thread-safe.

pub fn traitCollectionWithLayoutDirection( layout_direction: UITraitEnvironmentLayoutDirection, ) -> Retained<UITraitCollection>

Available on crate feature UIInterface only.

pub unsafe fn layoutDirection(&self) -> UITraitEnvironmentLayoutDirection

Available on crate feature UIInterface only.

This property is not atomic.

Safety

This might not be thread-safe.

pub fn traitCollectionWithDisplayScale( scale: CGFloat, ) -> Retained<UITraitCollection>

Available on crate feature objc2-core-foundation only.

pub unsafe fn displayScale(&self) -> CGFloat

Available on crate feature objc2-core-foundation only.

This property is not atomic.

Safety

This might not be thread-safe.

pub fn traitCollectionWithHorizontalSizeClass( horizontal_size_class: UIUserInterfaceSizeClass, ) -> Retained<UITraitCollection>

Available on crate feature UIInterface only.

pub unsafe fn horizontalSizeClass(&self) -> UIUserInterfaceSizeClass

Available on crate feature UIInterface only.

This property is not atomic.

Safety

This might not be thread-safe.

pub fn traitCollectionWithVerticalSizeClass( vertical_size_class: UIUserInterfaceSizeClass, ) -> Retained<UITraitCollection>

Available on crate feature UIInterface only.

pub unsafe fn verticalSizeClass(&self) -> UIUserInterfaceSizeClass

Available on crate feature UIInterface only.

This property is not atomic.

Safety

This might not be thread-safe.

pub fn traitCollectionWithForceTouchCapability( capability: UIForceTouchCapability, ) -> Retained<UITraitCollection>

Available on crate feature UITouch only.

pub fn forceTouchCapability(&self) -> UIForceTouchCapability

Available on crate feature UITouch only.

This property is not atomic.

pub fn traitCollectionWithPreferredContentSizeCategory( preferred_content_size_category: &UIContentSizeCategory, ) -> Retained<UITraitCollection>

Available on crate feature UIContentSizeCategory only.

pub unsafe fn preferredContentSizeCategory( &self, ) -> Retained<UIContentSizeCategory>

Available on crate feature UIContentSizeCategory only.

This property is not atomic.

Safety

This might not be thread-safe.

pub fn traitCollectionWithDisplayGamut( display_gamut: UIDisplayGamut, ) -> Retained<UITraitCollection>

Available on crate feature UIInterface only.

pub unsafe fn displayGamut(&self) -> UIDisplayGamut

Available on crate feature UIInterface only.

This property is not atomic.

Safety

This might not be thread-safe.

pub fn traitCollectionWithAccessibilityContrast( accessibility_contrast: UIAccessibilityContrast, ) -> Retained<UITraitCollection>

Available on crate feature UIInterface only.

pub unsafe fn accessibilityContrast(&self) -> UIAccessibilityContrast

Available on crate feature UIInterface only.

This property is not atomic.

Safety

This might not be thread-safe.

pub fn traitCollectionWithUserInterfaceLevel( user_interface_level: UIUserInterfaceLevel, ) -> Retained<UITraitCollection>

Available on crate feature UIInterface only.

pub unsafe fn userInterfaceLevel(&self) -> UIUserInterfaceLevel

Available on crate feature UIInterface only.

This property is not atomic.

Safety

This might not be thread-safe.

pub fn traitCollectionWithLegibilityWeight( legibility_weight: UILegibilityWeight, ) -> Retained<UITraitCollection>

Available on crate feature UIInterface only.

pub unsafe fn legibilityWeight(&self) -> UILegibilityWeight

Available on crate feature UIInterface only.

This property is not atomic.

Safety

This might not be thread-safe.

pub fn traitCollectionWithActiveAppearance( user_interface_active_appearance: UIUserInterfaceActiveAppearance, ) -> Retained<UITraitCollection>

Available on crate feature UIInterface only.

pub unsafe fn activeAppearance(&self) -> UIUserInterfaceActiveAppearance

Available on crate feature UIInterface only.

This property is not atomic.

Safety

This might not be thread-safe.

pub fn traitCollectionWithToolbarItemPresentationSize( toolbar_item_presentation_size: UINSToolbarItemPresentationSize, ) -> Retained<UITraitCollection>

Available on crate feature UIInterface only.

pub unsafe fn toolbarItemPresentationSize( &self, ) -> UINSToolbarItemPresentationSize

Available on crate feature UIInterface only.

This property is not atomic.

Safety

This might not be thread-safe.

pub fn traitCollectionWithImageDynamicRange( image_dynamic_range: UIImageDynamicRange, ) -> Retained<UITraitCollection>

Available on crate feature UIInterface only.

Construct a new trait collection with the given image content dynamic range.

pub unsafe fn imageDynamicRange(&self) -> UIImageDynamicRange

Available on crate feature UIInterface only.

The imageDynamicRange determines how HDR images will render in the given trait environment. SDR images are unaffected.

This property is not atomic.

Safety

This might not be thread-safe.

pub fn traitCollectionWithTypesettingLanguage( language: &NSString, ) -> Retained<UITraitCollection>

pub unsafe fn typesettingLanguage(&self) -> Retained<NSString>

This property is not atomic.

Safety

This might not be thread-safe.

pub fn traitCollectionWithSceneCaptureState( scene_capture_state: UISceneCaptureState, ) -> Retained<UITraitCollection>

Available on crate feature UISceneDefinitions only.

Construct a new trait collection with the given scene capture state.

pub unsafe fn sceneCaptureState(&self) -> UISceneCaptureState

Available on crate feature UISceneDefinitions only.

Scene capture state represents whether a scene is currently being mirrored or recorded.

This property is not atomic.

Safety

This might not be thread-safe.

pub fn traitCollectionWithListEnvironment( list_environment: UIListEnvironment, ) -> Retained<UITraitCollection>

Available on crate feature UITraitListEnvironment only.

Construct a new trait collection with the given listEnvironment.

pub unsafe fn listEnvironment(&self) -> UIListEnvironment

Available on crate feature UITraitListEnvironment only.

The list environment represents whether a given trait collection is from a view in a UITableView or a UICollectionView list section.

This property is not atomic.

Safety

This might not be thread-safe.

pub fn traitCollectionWithTabAccessoryEnvironment( tab_accessory_environment: UITabAccessoryEnvironment, ) -> Retained<UITraitCollection>

Available on crate feature UITabAccessory only.

Constructs a new trait collection with the given tabAccessoryEnvironment.

pub unsafe fn tabAccessoryEnvironment(&self) -> UITabAccessoryEnvironment

Available on crate feature UITabAccessory only.

The tab accessory environment represents whether a given trait collection is from a view in a UITabAccessory content view.

This property is not atomic.

Safety

This might not be thread-safe.

pub unsafe fn splitViewControllerLayoutEnvironment( &self, ) -> UISplitViewControllerLayoutEnvironment

Available on crate feature UISplitViewControllerLayoutEnvironment only.

The split view controller layout environment represents whether an ancestor split view controller is expanded or collapsed.

This property is not atomic.

Safety

This might not be thread-safe.

pub unsafe fn hdrHeadroomUsageLimit(&self) -> UIHDRHeadroomUsageLimit

Available on crate feature UIInterface only.

If HDR headroom should be used for the current UI configuration. Headroom usage is disabled in certain UI configurations, such as when all an application’s windows are in the background.

This property is not atomic.

Safety

This might not be thread-safe.

pub fn traitCollectionWithHDRHeadroomUsageLimit( hdr_headroom_usage_limit: UIHDRHeadroomUsageLimit, ) -> Retained<UITraitCollection>

Available on crate feature UIInterface only.

pub fn traitCollectionWithResolvesNaturalAlignmentWithBaseWritingDirection( resolves_natural_alignment_with_base_writing_direction: bool, ) -> Retained<UITraitCollection>

pub unsafe fn resolvesNaturalAlignmentWithBaseWritingDirection(&self) -> bool

Specifies the behavior for resolving NSTextAlignment.natural to the visual alignment.

When set to true, the resolved visual alignment is determined by the resolved base writing direction; otherwise, it is using the user’s preferred language.

This property is not atomic.

Safety

This might not be thread-safe.

impl UITraitCollection

Methods declared on superclass NSObject.

pub fn new() -> Retained<Self>

impl UITraitCollection

pub unsafe fn traitCollectionWithTraits( mutations: UITraitMutations, ) -> Retained<UITraitCollection>

Available on crate feature block2 only.

Safety

mutations must be a valid pointer.

pub unsafe fn traitCollectionByModifyingTraits( &self, mutations: UITraitMutations, ) -> Retained<UITraitCollection>

Available on crate feature block2 only.

Safety

mutations must be a valid pointer.

pub unsafe fn traitCollectionWithCGFloatValue_forTrait( value: CGFloat, trait: &UICGFloatTrait, ) -> Retained<UITraitCollection>

Available on crate features UITrait and objc2-core-foundation only.

Safety

trait must implement UICGFloatTraitDefinition.

pub unsafe fn traitCollectionByReplacingCGFloatValue_forTrait( &self, value: CGFloat, trait: &UICGFloatTrait, ) -> Retained<UITraitCollection>

Available on crate features UITrait and objc2-core-foundation only.

Safety

trait must implement UICGFloatTraitDefinition.

pub unsafe fn valueForCGFloatTrait(&self, trait: &UICGFloatTrait) -> CGFloat

Available on crate features UITrait and objc2-core-foundation only.

Safety

trait must implement UICGFloatTraitDefinition.

pub unsafe fn traitCollectionWithNSIntegerValue_forTrait( value: NSInteger, trait: &UINSIntegerTrait, ) -> Retained<UITraitCollection>

Available on crate feature UITrait only.

Safety

trait must implement UINSIntegerTraitDefinition.

pub unsafe fn traitCollectionByReplacingNSIntegerValue_forTrait( &self, value: NSInteger, trait: &UINSIntegerTrait, ) -> Retained<UITraitCollection>

Available on crate feature UITrait only.

Safety

trait must implement UINSIntegerTraitDefinition.

pub unsafe fn valueForNSIntegerTrait( &self, trait: &UINSIntegerTrait, ) -> NSInteger

Available on crate feature UITrait only.

Safety

trait must implement UINSIntegerTraitDefinition.

pub unsafe fn traitCollectionWithObject_forTrait( object: Option<&ProtocolObject<dyn NSObjectProtocol>>, trait: &UIObjectTrait, ) -> Retained<UITraitCollection>

Available on crate feature UITrait only.

Safety

• object should be of the correct type.
• trait must implement UIObjectTraitDefinition.

pub unsafe fn traitCollectionByReplacingObject_forTrait( &self, object: Option<&ProtocolObject<dyn NSObjectProtocol>>, trait: &UIObjectTrait, ) -> Retained<UITraitCollection>

Available on crate feature UITrait only.

Safety

• object should be of the correct type.
• trait must implement UIObjectTraitDefinition.

pub unsafe fn objectForTrait( &self, trait: &UIObjectTrait, ) -> Option<Retained<ProtocolObject<dyn NSObjectProtocol>>>

Available on crate feature UITrait only.

Safety

trait must implement UIObjectTraitDefinition.

impl UITraitCollection

CurrentTraitCollection.

pub unsafe fn currentTraitCollection() -> Retained<UITraitCollection>

This property is not atomic.

Safety

This might not be thread-safe.

pub unsafe fn setCurrentTraitCollection( current_trait_collection: &UITraitCollection, )

Setter for currentTraitCollection.

Safety

This might not be thread-safe.

pub fn performAsCurrentTraitCollection(&self, actions: &DynBlock<dyn Fn() + '_>)

Available on crate feature block2 only.

impl UITraitCollection

DynamicAppearance.

pub fn hasDifferentColorAppearanceComparedToTraitCollection( &self, trait_collection: Option<&UITraitCollection>, ) -> bool

impl UITraitCollection

ImageConfiguration.

pub unsafe fn imageConfiguration(&self) -> Retained<UIImageConfiguration>

Available on crate feature UIImageConfiguration only.

This property is not atomic.

Safety

This might not be thread-safe.

Methods from Deref<Target = NSObject>

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

Handle messages the object doesn’t recognize.

See Apple’s documentation for details.

Methods from Deref<Target = AnyObject>

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

Available on crate feature 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());

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

where T: Encode,

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

Available on crate feature 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.

pub fn downcast_ref<T>(&self) -> Option<&T>

where T: DowncastTarget,

Available on crate feature 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

impl AsRef<AnyObject> for UITraitCollection

fn as_ref(&self) -> &AnyObject

Converts this type into a shared reference of the (usually inferred) input type.

impl AsRef<NSObject> for UITraitCollection

fn as_ref(&self) -> &NSObject

Converts this type into a shared reference of the (usually inferred) input type.

impl AsRef<UITraitCollection> for UITraitCollection

fn as_ref(&self) -> &Self

Converts this type into a shared reference of the (usually inferred) input type.

impl Borrow<AnyObject> for UITraitCollection

fn borrow(&self) -> &AnyObject

Immutably borrows from an owned value.

impl Borrow<NSObject> for UITraitCollection

fn borrow(&self) -> &NSObject

Immutably borrows from an owned value.

impl ClassType for UITraitCollection

const NAME: &'static str = "UITraitCollection"

The name of the Objective-C class that this type represents.

type Super = NSObject

The superclass of this class.

type ThreadKind = <<UITraitCollection as ClassType>::Super as ClassType>::ThreadKind

Whether the type can be used from any thread, or from only the main thread.

fn class() -> &'static AnyClass

Get a reference to the Objective-C class that this type represents.

fn as_super(&self) -> &Self::Super

Get an immutable reference to the superclass.

impl CopyingHelper for UITraitCollection

type Result = UITraitCollection

The immutable counterpart of the type, or Self if the type has no immutable counterpart.

impl Debug for UITraitCollection

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl DefaultRetained for UITraitCollection

fn default_retained() -> Retained<Self>

The default Retained for a type.

impl Deref for UITraitCollection

type Target = NSObject

The resulting type after dereferencing.

fn deref(&self) -> &Self::Target

Dereferences the value.

impl Hash for UITraitCollection

fn hash<H: Hasher>(&self, state: &mut H)

Feeds this value into the given Hasher.

fn hash_slice<H>(data: &[Self], state: &mut H)

where H: Hasher, Self: Sized,

Feeds a slice of this type into the given Hasher.

impl Message for UITraitCollection

fn retain(&self) -> Retained<Self>

where Self: Sized,

Increment the reference count of the receiver.

impl NSCoding for UITraitCollection

unsafe fn encodeWithCoder(&self, coder: &NSCoder)

where Self: Sized + Message,

Safety

unsafe fn initWithCoder( this: Allocated<Self>, coder: &NSCoder, ) -> Option<Retained<Self>>

where Self: Sized + Message,

Safety

impl NSCopying for UITraitCollection

fn copy(&self) -> Retained<Self::Result>

where Self: Sized + Message + CopyingHelper,

Returns a new instance that’s a copy of the receiver.

unsafe fn copyWithZone(&self, zone: *mut NSZone) -> Retained<Self::Result>

where Self: Sized + Message + CopyingHelper,

Returns a new instance that’s a copy of the receiver.

impl NSObjectProtocol for UITraitCollection

fn isEqual(&self, other: Option<&AnyObject>) -> bool

where Self: Sized + Message,

Check whether the object is equal to an arbitrary other object.

fn hash(&self) -> usize

where Self: Sized + Message,

An integer that can be used as a table address in a hash table structure.

fn isKindOfClass(&self, cls: &AnyClass) -> bool

where Self: Sized + Message,

Check if the object is an instance of the class, or one of its subclasses.

fn is_kind_of<T>(&self) -> bool

where T: ClassType, Self: Sized + Message,

👎Deprecated: use isKindOfClass directly, or cast your objects with AnyObject::downcast_ref

Check if the object is an instance of the class type, or one of its subclasses.

fn isMemberOfClass(&self, cls: &AnyClass) -> bool

where Self: Sized + Message,

Check if the object is an instance of a specific class, without checking subclasses.

fn respondsToSelector(&self, aSelector: Sel) -> bool

where Self: Sized + Message,

Check whether the object implements or inherits a method with the given selector.

fn conformsToProtocol(&self, aProtocol: &AnyProtocol) -> bool

where Self: Sized + Message,

Check whether the object conforms to a given protocol.

fn description(&self) -> Retained<NSObject>

where Self: Sized + Message,

A textual representation of the object.

fn debugDescription(&self) -> Retained<NSObject>

where Self: Sized + Message,

A textual representation of the object to use when debugging.

fn isProxy(&self) -> bool

where Self: Sized + Message,

Check whether the receiver is a subclass of the NSProxy root class instead of the usual NSObject.

fn retainCount(&self) -> usize

where Self: Sized + Message,

The reference count of the object.

impl NSSecureCoding for UITraitCollection

fn supportsSecureCoding() -> bool

where Self: Sized + ClassType,

impl PartialEq for UITraitCollection

fn eq(&self, other: &Self) -> bool

Tests for self and other values to be equal, and is used by ==.

fn ne(&self, other: &Rhs) -> bool

Tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.

impl RefEncode for UITraitCollection

const ENCODING_REF: Encoding = <NSObject as ::objc2::RefEncode>::ENCODING_REF

The Objective-C type-encoding for a reference of this type.

impl DowncastTarget for UITraitCollection

impl Eq for UITraitCollection

impl Send for UITraitCollection

impl Sync for UITraitCollection