Struct BGProcessingTaskRequest 

pub struct BGProcessingTaskRequest { /* private fields */ }

Available on crate feature BGTaskRequest only.

A request to launch your app in the background to execute a processing task that can take minutes to complete.

Schedule a processing task request to ask that the system launch your app when conditions are favorable for battery life to handle deferrable, longer-running processing, such as syncing, database maintenance, or similar tasks. The system will attempt to fulfill this request to the best of its ability within the next two days as long as the user has used your app within the past week.

See also Apple’s documentation

Implementations

impl BGProcessingTaskRequest

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

Return a new processing task request for the specified identifier.

• Parameters:
• identifier: The string identifier of the processing task associated with the request.

pub unsafe fn requiresNetworkConnectivity(&self) -> bool

A Boolean specifying if the processing task requires network connectivity.

If this property is set to YES, the system will only launch your app to fulfill this request when the device has a network connection. If this is set to NO, your app may not have network access.

• Note: The default value is NO.

pub unsafe fn setRequiresNetworkConnectivity( &self, requires_network_connectivity: bool, )

Setter for requiresNetworkConnectivity.

pub unsafe fn requiresExternalPower(&self) -> bool

Whether the background task represented by this request should only be done while the device is connected to external power.

If this property is set to YES, the system will launch your app to fulfill this request only while the device is connected to external power. Setting this to YES will also disable the CPU Monitor feature. Specify YES if this task is resource intensive to minimize impact to battery life. Please note that, even if this value is NO, the system will not necessarily schedule this task while the device is on battery power, depending on the type of device and system conditions.

• Note: The default value is NO.

pub unsafe fn setRequiresExternalPower(&self, requires_external_power: bool)

Setter for requiresExternalPower.

impl BGProcessingTaskRequest

Methods declared on superclass BGTaskRequest.

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

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

Methods from Deref<Target = BGTaskRequest>

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

The identifier of the task associated with the request.

pub unsafe fn earliestBeginDate(&self) -> Option<Retained<NSDate>>

The earliest date and time at which to run the task.

Specify nil for no start delay.

Setting the property indicates that the background task shouldn’t start any earlier than this date. However, the system doesn’t guarantee launching the task at the specified date, but only that it won’t begin sooner.

pub unsafe fn setEarliestBeginDate(&self, earliest_begin_date: Option<&NSDate>)

Setter for earliestBeginDate.

This is copied when set.

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.

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.

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 BGProcessingTaskRequest

fn as_ref(&self) -> &AnyObject

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

impl AsRef<BGProcessingTaskRequest> for BGHealthResearchTaskRequest

fn as_ref(&self) -> &BGProcessingTaskRequest

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

impl AsRef<BGProcessingTaskRequest> for BGProcessingTaskRequest

fn as_ref(&self) -> &Self

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

impl AsRef<BGTaskRequest> for BGProcessingTaskRequest

fn as_ref(&self) -> &BGTaskRequest

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

impl AsRef<NSObject> for BGProcessingTaskRequest

fn as_ref(&self) -> &NSObject

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

impl Borrow<AnyObject> for BGProcessingTaskRequest

fn borrow(&self) -> &AnyObject

Immutably borrows from an owned value.

impl Borrow<BGProcessingTaskRequest> for BGHealthResearchTaskRequest

fn borrow(&self) -> &BGProcessingTaskRequest

Immutably borrows from an owned value.

impl Borrow<BGTaskRequest> for BGProcessingTaskRequest

fn borrow(&self) -> &BGTaskRequest

Immutably borrows from an owned value.

impl Borrow<NSObject> for BGProcessingTaskRequest

fn borrow(&self) -> &NSObject

Immutably borrows from an owned value.

impl ClassType for BGProcessingTaskRequest

const NAME: &'static str = "BGProcessingTaskRequest"

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

type Super = BGTaskRequest

The superclass of this class.

type ThreadKind = <<BGProcessingTaskRequest 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 BGProcessingTaskRequest

type Result = BGProcessingTaskRequest

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

impl Debug for BGProcessingTaskRequest

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

Formats the value using the given formatter.

impl Deref for BGProcessingTaskRequest

type Target = BGTaskRequest

The resulting type after dereferencing.

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

Dereferences the value.

impl Hash for BGProcessingTaskRequest

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 BGProcessingTaskRequest

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

where Self: Sized,

Increment the reference count of the receiver.

impl NSCopying for BGProcessingTaskRequest

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 BGProcessingTaskRequest

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 BGProcessingTaskRequest

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 BGProcessingTaskRequest

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

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

impl DowncastTarget for BGProcessingTaskRequest

impl Eq for BGProcessingTaskRequest