Struct UINavigationItem

#[repr(C)]
pub struct UINavigationItem { /* private fields */ }

Available on crate feature UINavigationItem only.

Apple’s documentation

Implementations

impl UINavigationItem

pub unsafe fn initWithTitle( this: Allocated<Self>, title: &NSString, ) -> Retained<Self>

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

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

Title when topmost on the stack. default is nil

pub unsafe fn setTitle(&self, title: Option<&NSString>)

Setter for title.

pub unsafe fn titleView(&self) -> Option<Retained<UIView>>

Available on crate features UIResponder and UIView only.

Custom view to use in lieu of a title. May be sized horizontally. Only used when item is topmost on the stack.

pub unsafe fn setTitleView(&self, title_view: Option<&UIView>)

Available on crate features UIResponder and UIView only.

Setter for titleView.

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

Explanatory text to display above the navigation bar buttons.

pub unsafe fn setPrompt(&self, prompt: Option<&NSString>)

Setter for prompt.

pub unsafe fn backBarButtonItem(&self) -> Option<Retained<UIBarButtonItem>>

Available on crate features UIBarButtonItem and UIBarItem only.

Bar button item to use for the back button when this item is the navigation bar’s backItem.

pub unsafe fn setBackBarButtonItem( &self, back_bar_button_item: Option<&UIBarButtonItem>, )

Available on crate features UIBarButtonItem and UIBarItem only.

Setter for backBarButtonItem.

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

Title to use when this item is the navigation bar’s backItem. Default is nil. backBarButtonItem takes precedence if both are specified.

pub unsafe fn setBackButtonTitle(&self, back_button_title: Option<&NSString>)

Setter for backButtonTitle.

pub unsafe fn hidesBackButton(&self) -> bool

If YES, this navigation item will hide the back button when it’s on top of the stack.

pub unsafe fn setHidesBackButton(&self, hides_back_button: bool)

Setter for hidesBackButton.

pub unsafe fn setHidesBackButton_animated( &self, hides_back_button: bool, animated: bool, )

pub unsafe fn backButtonDisplayMode( &self, ) -> UINavigationItemBackButtonDisplayMode

Controls how the back button sources its title.

pub unsafe fn setBackButtonDisplayMode( &self, back_button_display_mode: UINavigationItemBackButtonDisplayMode, )

Setter for backButtonDisplayMode.

pub unsafe fn backAction(&self) -> Option<Retained<UIAction>>

Available on crate features UIAction and UIMenuElement only.

Replaces the back action for the navigation bar. if a back button is naturally present, this replaces only its action, otherwise a back button will be synthesized with the image or title from the action.

pub unsafe fn setBackAction(&self, back_action: Option<&UIAction>)

Available on crate features UIAction and UIMenuElement only.

Setter for backAction.

pub unsafe fn titleMenuProvider( &self, ) -> *mut Block<dyn Fn(NonNull<NSArray<UIMenuElement>>) -> *mut UIMenu>

Available on crate features UIMenu and UIMenuElement and block2 only.

When non-nil, UIKit will generate suggestedActions and call this block to generate a menu that is displayed from the title.

pub unsafe fn setTitleMenuProvider( &self, title_menu_provider: Option<&Block<dyn Fn(NonNull<NSArray<UIMenuElement>>) -> *mut UIMenu>>, )

Available on crate features UIMenu and UIMenuElement and block2 only.

Setter for titleMenuProvider.

pub unsafe fn renameDelegate( &self, ) -> Option<Retained<ProtocolObject<dyn UINavigationItemRenameDelegate>>>

When non-nil, enables the UINavigationBar to respond to the rename: action by providing an inline UI. Setting this property to nil while a rename operation is in progress will cancel the operation immediately.

pub unsafe fn setRenameDelegate( &self, rename_delegate: Option<&ProtocolObject<dyn UINavigationItemRenameDelegate>>, )

This is a weak property. Setter for renameDelegate.

pub unsafe fn documentProperties( &self, ) -> Option<Retained<UIDocumentProperties>>

Available on crate feature UIDocumentProperties only.

When non-nil, UIKit will use the metadata provided to generate additional controls displayed from the title.

pub unsafe fn setDocumentProperties( &self, document_properties: Option<&UIDocumentProperties>, )

Available on crate feature UIDocumentProperties only.

Setter for documentProperties.

pub unsafe fn leftBarButtonItems( &self, ) -> Option<Retained<NSArray<UIBarButtonItem>>>

Available on crate features UIBarButtonItem and UIBarItem only.

pub unsafe fn setLeftBarButtonItems( &self, left_bar_button_items: Option<&NSArray<UIBarButtonItem>>, )

Available on crate features UIBarButtonItem and UIBarItem only.

Setter for leftBarButtonItems.

pub unsafe fn rightBarButtonItems( &self, ) -> Option<Retained<NSArray<UIBarButtonItem>>>

Available on crate features UIBarButtonItem and UIBarItem only.

pub unsafe fn setRightBarButtonItems( &self, right_bar_button_items: Option<&NSArray<UIBarButtonItem>>, )

Available on crate features UIBarButtonItem and UIBarItem only.

Setter for rightBarButtonItems.

pub unsafe fn setLeftBarButtonItems_animated( &self, items: Option<&NSArray<UIBarButtonItem>>, animated: bool, )

Available on crate features UIBarButtonItem and UIBarItem only.

pub unsafe fn setRightBarButtonItems_animated( &self, items: Option<&NSArray<UIBarButtonItem>>, animated: bool, )

Available on crate features UIBarButtonItem and UIBarItem only.

pub unsafe fn leftItemsSupplementBackButton(&self) -> bool

pub unsafe fn setLeftItemsSupplementBackButton( &self, left_items_supplement_back_button: bool, )

Setter for leftItemsSupplementBackButton.

pub unsafe fn leftBarButtonItem(&self) -> Option<Retained<UIBarButtonItem>>

Available on crate features UIBarButtonItem and UIBarItem only.

Some navigation items want to display a custom left or right item when they’re on top of the stack. A custom left item replaces the regular back button unless you set leftItemsSupplementBackButton to YES

pub unsafe fn setLeftBarButtonItem( &self, left_bar_button_item: Option<&UIBarButtonItem>, )

Available on crate features UIBarButtonItem and UIBarItem only.

Setter for leftBarButtonItem.

pub unsafe fn rightBarButtonItem(&self) -> Option<Retained<UIBarButtonItem>>

Available on crate features UIBarButtonItem and UIBarItem only.

pub unsafe fn setRightBarButtonItem( &self, right_bar_button_item: Option<&UIBarButtonItem>, )

Available on crate features UIBarButtonItem and UIBarItem only.

Setter for rightBarButtonItem.

pub unsafe fn setLeftBarButtonItem_animated( &self, item: Option<&UIBarButtonItem>, animated: bool, )

Available on crate features UIBarButtonItem and UIBarItem only.

pub unsafe fn setRightBarButtonItem_animated( &self, item: Option<&UIBarButtonItem>, animated: bool, )

Available on crate features UIBarButtonItem and UIBarItem only.

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

Setting a non-nil customizationIdentifier enables customization and UIKit will automatically save & restore customizations based on this identifier. The identifier must be unique within the scope of the application.

pub unsafe fn setCustomizationIdentifier( &self, customization_identifier: Option<&NSString>, )

Setter for customizationIdentifier.

pub unsafe fn leadingItemGroups( &self, ) -> Retained<NSArray<UIBarButtonItemGroup>>

Available on crate feature UIBarButtonItemGroup only.

UIBarButtonItemGroups to be displayed in the leading section of the navigation bar. Items set via this method will replace items set via .leftBarButtonItem or .leftBarButtonItems.

pub unsafe fn setLeadingItemGroups( &self, leading_item_groups: &NSArray<UIBarButtonItemGroup>, )

Available on crate feature UIBarButtonItemGroup only.

Setter for leadingItemGroups.

pub unsafe fn centerItemGroups(&self) -> Retained<NSArray<UIBarButtonItemGroup>>

Available on crate feature UIBarButtonItemGroup only.

Customizable UIBarButtonItemGroups that will be placed in the center region when the navigation bar is the browser or editor modes. In navigation mode, these items will be placed in the overflow.

pub unsafe fn setCenterItemGroups( &self, center_item_groups: &NSArray<UIBarButtonItemGroup>, )

Available on crate feature UIBarButtonItemGroup only.

Setter for centerItemGroups.

pub unsafe fn trailingItemGroups( &self, ) -> Retained<NSArray<UIBarButtonItemGroup>>

Available on crate feature UIBarButtonItemGroup only.

UIBarButtonItemGroups to be displayed in the trailing section of the navigation bar. Items set via this method will replace items set via .rightBarButtonItem or .rightBarButtonItems.

pub unsafe fn setTrailingItemGroups( &self, trailing_item_groups: &NSArray<UIBarButtonItemGroup>, )

Available on crate feature UIBarButtonItemGroup only.

Setter for trailingItemGroups.

pub unsafe fn pinnedTrailingGroup( &self, ) -> Option<Retained<UIBarButtonItemGroup>>

Available on crate feature UIBarButtonItemGroup only.

Set a group of items to be placed on the trailing edge of the bar, past the overflow & search items (if present). If you wish to have more than 1 item, it is HIGHLY recommended to assign a representative item to the group to avoid overflowing the bar as this group cannot move to the overflow.

pub unsafe fn setPinnedTrailingGroup( &self, pinned_trailing_group: Option<&UIBarButtonItemGroup>, )

Available on crate feature UIBarButtonItemGroup only.

Setter for pinnedTrailingGroup.

pub unsafe fn additionalOverflowItems( &self, ) -> Option<Retained<UIDeferredMenuElement>>

Available on crate features UIDeferredMenuElement and UIMenuElement only.

Additional items to add to the overflow menu. Setting this property to a non-nil value will force the overflow button to appear, regardless of if you provide any content in the element’s callback. Items returned are displayed directly in the presented menu.

pub unsafe fn setAdditionalOverflowItems( &self, additional_overflow_items: Option<&UIDeferredMenuElement>, )

Available on crate features UIDeferredMenuElement and UIMenuElement only.

Setter for additionalOverflowItems.

pub unsafe fn overflowPresentationSource( &self, ) -> Option<Retained<ProtocolObject<dyn UIPopoverPresentationControllerSourceItem>>>

Available on crate feature UIPopoverPresentationControllerSourceItem only.

If the overflow button for this item is currently present, then this will return a non-nil item that can be used as a presentation source (e.g. for popovers). Otherwise it will return nil.

pub unsafe fn largeTitleDisplayMode( &self, ) -> UINavigationItemLargeTitleDisplayMode

When UINavigationBar.prefersLargeTitles=YES, this property controls when the larger out-of-line title is displayed. If prefersLargeTitles=NO, this property has no effect. The default value is Automatic.

pub unsafe fn setLargeTitleDisplayMode( &self, large_title_display_mode: UINavigationItemLargeTitleDisplayMode, )

Setter for largeTitleDisplayMode.

pub unsafe fn style(&self) -> UINavigationItemStyle

Controls how content defined by this item is laid out in the navigation bar.

pub unsafe fn setStyle(&self, style: UINavigationItemStyle)

Setter for style.

pub unsafe fn searchController(&self) -> Option<Retained<UISearchController>>

Available on crate features UIResponder and UISearchController and UIViewController only.

A view controller that will be shown inside of a navigation controller can assign a UISearchController to this property to display the search controller’s search bar in its containing navigation controller’s navigation bar.

pub unsafe fn setSearchController( &self, search_controller: Option<&UISearchController>, )

Available on crate features UIResponder and UISearchController and UIViewController only.

Setter for searchController.

pub unsafe fn hidesSearchBarWhenScrolling(&self) -> bool

If this property is true (the default), the searchController’s search bar will hide as the user scrolls in the top view controller’s scroll view. If false, the search bar will remain visible and pinned underneath the navigation bar. Not appicable and ignored for UINavigationItemSearchBarPlacementInline

pub unsafe fn setHidesSearchBarWhenScrolling( &self, hides_search_bar_when_scrolling: bool, )

Setter for hidesSearchBarWhenScrolling.

pub unsafe fn preferredSearchBarPlacement( &self, ) -> UINavigationItemSearchBarPlacement

The preferred search bar placement, when a search controller is assigned to this item.

pub unsafe fn setPreferredSearchBarPlacement( &self, preferred_search_bar_placement: UINavigationItemSearchBarPlacement, )

Setter for preferredSearchBarPlacement.

pub unsafe fn searchBarPlacement(&self) -> UINavigationItemSearchBarPlacement

The realized placement. Only valid if a search controller has been assigned to this item.

pub unsafe fn standardAppearance( &self, ) -> Option<Retained<UINavigationBarAppearance>>

Available on crate features UIBarAppearance and UINavigationBarAppearance only.

When set and this item is topmost, overrides the hosting navigation bar’s standardAppearance. See UINavigationBar.standardAppearance for further details.

pub unsafe fn setStandardAppearance( &self, standard_appearance: Option<&UINavigationBarAppearance>, )

Available on crate features UIBarAppearance and UINavigationBarAppearance only.

Setter for standardAppearance.

pub unsafe fn compactAppearance( &self, ) -> Option<Retained<UINavigationBarAppearance>>

Available on crate features UIBarAppearance and UINavigationBarAppearance only.

When set and this item is topmost, overrides the hosting navigation bar’s compactAppearance. See UINavigationBar.compactAppearance for further details.

pub unsafe fn setCompactAppearance( &self, compact_appearance: Option<&UINavigationBarAppearance>, )

Available on crate features UIBarAppearance and UINavigationBarAppearance only.

Setter for compactAppearance.

pub unsafe fn scrollEdgeAppearance( &self, ) -> Option<Retained<UINavigationBarAppearance>>

Available on crate features UIBarAppearance and UINavigationBarAppearance only.

When set and this item is topmost, overrides the hosting navigation bar’s scrollEdgeAppearance. See UINavigationBar.scrollEdgeAppearance for further details.

pub unsafe fn setScrollEdgeAppearance( &self, scroll_edge_appearance: Option<&UINavigationBarAppearance>, )

Available on crate features UIBarAppearance and UINavigationBarAppearance only.

Setter for scrollEdgeAppearance.

pub unsafe fn compactScrollEdgeAppearance( &self, ) -> Option<Retained<UINavigationBarAppearance>>

Available on crate features UIBarAppearance and UINavigationBarAppearance only.

When set and this item is topmost, overrides the hosting navigation bar’s compactScrollEdgeAppearance. See UINavigationBar.h for further details.

pub unsafe fn setCompactScrollEdgeAppearance( &self, compact_scroll_edge_appearance: Option<&UINavigationBarAppearance>, )

Available on crate features UIBarAppearance and UINavigationBarAppearance only.

Setter for compactScrollEdgeAppearance.

impl UINavigationItem

Methods declared on superclass NSObject.

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

pub unsafe fn new(mtm: MainThreadMarker) -> Retained<Self>

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.

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 UINavigationItem

fn as_ref(&self) -> &AnyObject

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

impl AsRef<NSObject> for UINavigationItem

fn as_ref(&self) -> &NSObject

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

impl AsRef<UINavigationItem> for UINavigationItem

fn as_ref(&self) -> &Self

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

impl Borrow<AnyObject> for UINavigationItem

fn borrow(&self) -> &AnyObject

Immutably borrows from an owned value.

impl Borrow<NSObject> for UINavigationItem

fn borrow(&self) -> &NSObject

Immutably borrows from an owned value.

impl ClassType for UINavigationItem

const NAME: &'static str = "UINavigationItem"

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

type Super = NSObject

The superclass of this class.

type ThreadKind = dyn MainThreadOnly

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 Debug for UINavigationItem

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

Formats the value using the given formatter.

impl Deref for UINavigationItem

type Target = NSObject

The resulting type after dereferencing.

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

Dereferences the value.

impl Hash for UINavigationItem

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 UINavigationItem

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

where Self: Sized,

Increment the reference count of the receiver.

impl NSCoding for UINavigationItem

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

where Self: Sized + Message,

Available on crate feature NSCoder only.

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

where Self: Sized + Message,

Available on crate feature NSCoder only.

impl NSObjectProtocol for UINavigationItem

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 PartialEq for UINavigationItem

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 UINavigationItem

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

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

impl DowncastTarget for UINavigationItem

impl Eq for UINavigationItem