Struct WebBackForwardList

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

👎Deprecated

Available on crate feature WebBackForwardList only.

WebBackForwardList holds an ordered list of WebHistoryItems that comprises the back and forward lists.

Note that the methods which modify instances of this class do not cause navigation to happen in other layers of the stack; they are only for maintaining this data structure.

See also Apple’s documentation

Implementations

impl WebBackForwardList

pub unsafe fn addItem(&self, item: Option<&WebHistoryItem>)

👎Deprecated

Available on crate feature WebHistoryItem only.

Adds an entry to the list.

Parameter item: The entry to add.

The added entry is inserted immediately after the current entry. If the current position in the list is not at the end of the list, elements in the forward list will be dropped at this point. In addition, entries may be dropped to keep the size of the list within the maximum size.

pub unsafe fn goBack(&self)

👎Deprecated

Move the current pointer back to the entry before the current entry.

pub unsafe fn goForward(&self)

👎Deprecated

Move the current pointer ahead to the entry after the current entry.

pub unsafe fn goToItem(&self, item: Option<&WebHistoryItem>)

👎Deprecated

Available on crate feature WebHistoryItem only.

Move the current pointer to the given entry.

Parameter item: The history item to move the pointer to

pub unsafe fn backItem(&self) -> Option<Retained<WebHistoryItem>>

👎Deprecated

Available on crate feature WebHistoryItem only.

The entry right before the current entry, or nil if there isn’t one.

pub unsafe fn currentItem(&self) -> Option<Retained<WebHistoryItem>>

👎Deprecated

Available on crate feature WebHistoryItem only.

Returns the current entry.

pub unsafe fn forwardItem(&self) -> Option<Retained<WebHistoryItem>>

👎Deprecated

Available on crate feature WebHistoryItem only.

The entry right after the current entry, or nil if there isn’t one.

pub unsafe fn backListWithLimit( &self, limit: c_int, ) -> Option<Retained<NSArray>>

👎Deprecated

Returns a portion of the list before the current entry.

Parameter limit: A cap on the size of the array returned.

Returns: An array of items before the current entry, or nil if there are none. The entries are in the order that they were originally visited.

pub unsafe fn forwardListWithLimit( &self, limit: c_int, ) -> Option<Retained<NSArray>>

👎Deprecated

Returns a portion of the list after the current entry.

Parameter limit: A cap on the size of the array returned.

Returns: An array of items after the current entry, or nil if there are none. The entries are in the order that they were originally visited.

pub unsafe fn capacity(&self) -> c_int

👎Deprecated

The list’s maximum size.

pub unsafe fn setCapacity(&self, capacity: c_int)

👎Deprecated

Setter for capacity.

pub unsafe fn backListCount(&self) -> c_int

👎Deprecated

The number of items in the list.

pub unsafe fn forwardListCount(&self) -> c_int

👎Deprecated

Returns: The number of items in the list.

pub unsafe fn containsItem(&self, item: Option<&WebHistoryItem>) -> bool

👎Deprecated

Available on crate feature WebHistoryItem only.

Parameter item: The item that will be checked for presence in the WebBackForwardList.

Returns: Returns YES if the item is in the list.

pub unsafe fn itemAtIndex( &self, index: c_int, ) -> Option<Retained<WebHistoryItem>>

👎Deprecated

Available on crate feature WebHistoryItem only.

Returns an entry the given distance from the current entry.

Parameter index: Index of the desired list item relative to the current item; 0 is current item, -1 is back item, 1 is forward item, etc.

Returns: The entry the given distance from the current entry. If index exceeds the limits of the list, nil is returned.

impl WebBackForwardList

Methods declared on superclass NSObject.

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

pub unsafe fn new() -> Retained<Self>

impl WebBackForwardList

WebBackForwardListDeprecated.

pub unsafe fn setPageCacheSize(&self, size: NSUInteger)

👎Deprecated

The size passed to this method determines whether the WebView associated with this WebBackForwardList will use the shared page cache.

Parameter size: If size is 0, the WebView associated with this WebBackForwardList will not use the shared page cache. Otherwise, it will.

pub unsafe fn pageCacheSize(&self) -> NSUInteger

👎Deprecated

Returns the size of the shared page cache, or 0.

Returns: The size of the shared page cache (in pages), or 0 if the WebView associated with this WebBackForwardList will not use the shared page cache.

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

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.

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,

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 WebBackForwardList

fn as_ref(&self) -> &AnyObject

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

impl AsRef<NSObject> for WebBackForwardList

fn as_ref(&self) -> &NSObject

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

impl AsRef<WebBackForwardList> for WebBackForwardList

fn as_ref(&self) -> &Self

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

impl Borrow<AnyObject> for WebBackForwardList

fn borrow(&self) -> &AnyObject

Immutably borrows from an owned value.

impl Borrow<NSObject> for WebBackForwardList

fn borrow(&self) -> &NSObject

Immutably borrows from an owned value.

impl ClassType for WebBackForwardList

const NAME: &'static str = "WebBackForwardList"

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

type Super = NSObject

The superclass of this class.

type ThreadKind = <<WebBackForwardList 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 Debug for WebBackForwardList

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

Formats the value using the given formatter.

impl Deref for WebBackForwardList

type Target = NSObject

The resulting type after dereferencing.

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

Dereferences the value.

impl Hash for WebBackForwardList

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 WebBackForwardList

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

where Self: Sized,

Increment the reference count of the receiver.

impl NSObjectProtocol for WebBackForwardList

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 WebBackForwardList

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 WebBackForwardList

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

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

impl DowncastTarget for WebBackForwardList

impl Eq for WebBackForwardList