Struct NSFetchRequest

#[repr(C)]
pub struct NSFetchRequest<ResultType: ?Sized = AnyObject> { /* private fields */ }

Available on crate features NSFetchRequest and NSPersistentStoreRequest only.

Apple’s documentation

Implementations

impl<ResultType: Message> NSFetchRequest<ResultType>

pub unsafe fn fetchRequestWithEntityName( entity_name: &NSString, ) -> Retained<Self>

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

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

pub unsafe fn execute( &self, ) -> Result<Retained<NSArray<ResultType>>, Retained<NSError>>

pub unsafe fn entity(&self) -> Option<Retained<NSEntityDescription>>

Available on crate feature NSEntityDescription only.

pub unsafe fn setEntity(&self, entity: Option<&NSEntityDescription>)

Available on crate feature NSEntityDescription only.

Setter for entity.

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

pub unsafe fn predicate(&self) -> Option<Retained<NSPredicate>>

pub unsafe fn setPredicate(&self, predicate: Option<&NSPredicate>)

Setter for predicate.

pub unsafe fn sortDescriptors( &self, ) -> Option<Retained<NSArray<NSSortDescriptor>>>

pub unsafe fn setSortDescriptors( &self, sort_descriptors: Option<&NSArray<NSSortDescriptor>>, )

Setter for sortDescriptors.

pub unsafe fn fetchLimit(&self) -> NSUInteger

pub unsafe fn setFetchLimit(&self, fetch_limit: NSUInteger)

Setter for fetchLimit.

pub unsafe fn affectedStores( &self, ) -> Option<Retained<NSArray<NSPersistentStore>>>

Available on crate feature NSPersistentStore only.

pub unsafe fn setAffectedStores( &self, affected_stores: Option<&NSArray<NSPersistentStore>>, )

Available on crate feature NSPersistentStore only.

Setter for affectedStores.

pub unsafe fn resultType(&self) -> NSFetchRequestResultType

pub unsafe fn setResultType(&self, result_type: NSFetchRequestResultType)

Setter for resultType.

pub unsafe fn includesSubentities(&self) -> bool

pub unsafe fn setIncludesSubentities(&self, includes_subentities: bool)

Setter for includesSubentities.

pub unsafe fn includesPropertyValues(&self) -> bool

pub unsafe fn setIncludesPropertyValues(&self, includes_property_values: bool)

Setter for includesPropertyValues.

pub unsafe fn returnsObjectsAsFaults(&self) -> bool

pub unsafe fn setReturnsObjectsAsFaults(&self, returns_objects_as_faults: bool)

Setter for returnsObjectsAsFaults.

pub unsafe fn relationshipKeyPathsForPrefetching( &self, ) -> Option<Retained<NSArray<NSString>>>

pub unsafe fn setRelationshipKeyPathsForPrefetching( &self, relationship_key_paths_for_prefetching: Option<&NSArray<NSString>>, )

Setter for relationshipKeyPathsForPrefetching.

pub unsafe fn includesPendingChanges(&self) -> bool

pub unsafe fn setIncludesPendingChanges(&self, includes_pending_changes: bool)

Setter for includesPendingChanges.

pub unsafe fn returnsDistinctResults(&self) -> bool

pub unsafe fn setReturnsDistinctResults(&self, returns_distinct_results: bool)

Setter for returnsDistinctResults.

pub unsafe fn propertiesToFetch(&self) -> Option<Retained<NSArray>>

pub unsafe fn setPropertiesToFetch(&self, properties_to_fetch: Option<&NSArray>)

Setter for propertiesToFetch.

pub unsafe fn fetchOffset(&self) -> NSUInteger

pub unsafe fn setFetchOffset(&self, fetch_offset: NSUInteger)

Setter for fetchOffset.

pub unsafe fn fetchBatchSize(&self) -> NSUInteger

pub unsafe fn setFetchBatchSize(&self, fetch_batch_size: NSUInteger)

Setter for fetchBatchSize.

pub unsafe fn shouldRefreshRefetchedObjects(&self) -> bool

pub unsafe fn setShouldRefreshRefetchedObjects( &self, should_refresh_refetched_objects: bool, )

Setter for shouldRefreshRefetchedObjects.

pub unsafe fn propertiesToGroupBy(&self) -> Option<Retained<NSArray>>

pub unsafe fn setPropertiesToGroupBy( &self, properties_to_group_by: Option<&NSArray>, )

Setter for propertiesToGroupBy.

pub unsafe fn havingPredicate(&self) -> Option<Retained<NSPredicate>>

pub unsafe fn setHavingPredicate(&self, having_predicate: Option<&NSPredicate>)

Setter for havingPredicate.

impl<ResultType: Message> NSFetchRequest<ResultType>

Methods declared on superclass NSObject.

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

Methods from Deref<Target = NSPersistentStoreRequest>

pub unsafe fn affectedStores( &self, ) -> Option<Retained<NSArray<NSPersistentStore>>>

Available on crate feature NSPersistentStore only.

pub unsafe fn setAffectedStores( &self, affected_stores: Option<&NSArray<NSPersistentStore>>, )

Available on crate feature NSPersistentStore only.

Setter for affectedStores.

pub unsafe fn requestType(&self) -> NSPersistentStoreRequestType

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<ResultType: ?Sized + Message> AsRef<AnyObject> for NSFetchRequest<ResultType>

fn as_ref(&self) -> &AnyObject

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

impl<ResultType: ?Sized + Message> AsRef<NSFetchRequest<ResultType>> for NSFetchRequest<ResultType>

fn as_ref(&self) -> &Self

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

impl<ResultType: ?Sized + Message> AsRef<NSObject> for NSFetchRequest<ResultType>

fn as_ref(&self) -> &NSObject

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

impl<ResultType: ?Sized + Message> AsRef<NSPersistentStoreRequest> for NSFetchRequest<ResultType>

fn as_ref(&self) -> &NSPersistentStoreRequest

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

impl<ResultType: ?Sized + Message> Borrow<AnyObject> for NSFetchRequest<ResultType>

fn borrow(&self) -> &AnyObject

Immutably borrows from an owned value.

impl<ResultType: ?Sized + Message> Borrow<NSObject> for NSFetchRequest<ResultType>

fn borrow(&self) -> &NSObject

Immutably borrows from an owned value.

impl<ResultType: ?Sized + Message> Borrow<NSPersistentStoreRequest> for NSFetchRequest<ResultType>

fn borrow(&self) -> &NSPersistentStoreRequest

Immutably borrows from an owned value.

impl<ResultType: ?Sized + Message> ClassType for NSFetchRequest<ResultType>

const NAME: &'static str = "NSFetchRequest"

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

type Super = NSPersistentStoreRequest

The superclass of this class.

type ThreadKind = <<NSFetchRequest<ResultType> 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<ResultType: ?Sized + Message> CopyingHelper for NSFetchRequest<ResultType>

type Result = NSFetchRequest<ResultType>

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

impl<ResultType: ?Sized> Debug for NSFetchRequest<ResultType>

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

Formats the value using the given formatter.

impl<ResultType: ?Sized + Message> Deref for NSFetchRequest<ResultType>

type Target = NSPersistentStoreRequest

The resulting type after dereferencing.

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

Dereferences the value.

impl<ResultType: ?Sized> Hash for NSFetchRequest<ResultType>

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<ResultType: ?Sized + Message> Message for NSFetchRequest<ResultType>

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

where Self: Sized,

Increment the reference count of the receiver.

impl<ResultType: ?Sized + NSCoding> NSCoding for NSFetchRequest<ResultType>

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

where Self: Sized + Message,

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

where Self: Sized + Message,

impl<ResultType: ?Sized> NSCopying for NSFetchRequest<ResultType>

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<ResultType: ?Sized> NSObjectProtocol for NSFetchRequest<ResultType>

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<ResultType: ?Sized> PartialEq for NSFetchRequest<ResultType>

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<ResultType: ?Sized + Message> RefEncode for NSFetchRequest<ResultType>

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

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

impl DowncastTarget for NSFetchRequest<AnyObject>

impl<ResultType: ?Sized> Eq for NSFetchRequest<ResultType>