Struct AVCaptureSmartFramingMonitor 

pub struct AVCaptureSmartFramingMonitor { /* private fields */ }

Available on crate feature AVCaptureDevice only.

An object associated with a capture device that monitors the scene and suggests an optimal framing.

A smart framing monitor observes its associated device for objects of interest entering and exiting the camera’s field of view and recommends an optimal framing for good photographic composition. This framing recommendation consists of an aspect ratio and zoom factor. You may respond to the device’s framing recommendation by calling AVCaptureDevice/setDynamicAspectRatio:completionHandler: and setting AVCaptureDevice/videoZoomFactor on the associated device in whatever order best matches your animation between old and new framings.

See also Apple’s documentation

Implementations

impl AVCaptureSmartFramingMonitor

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

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

pub unsafe fn supportedFramings(&self) -> Retained<NSArray<AVCaptureFraming>>

An array of framings supported by the monitor in its current configuration.

The monitor is capable of recommending any of the framings in this array. This property is key-value observable and may change as the target capture device’s AVCaptureDevice/activeFormat property changes. This array contains the full set of framings supported by the monitor in the device’s current configuration. You must tell the monitor which smart framings you are interested in having recommended to you by setting the enabledFramings property.

pub unsafe fn enabledFramings(&self) -> Retained<NSArray<AVCaptureFraming>>

An array of framings that the monitor is allowed to suggest.

The monitor is capable of recommending any of the framings in the supportedFramings array. This property contains the subset of supportedFramings you would like to have recommended to you. You may set this property at any time while running your AVCaptureSession. This property’s default value is the empty array.

pub unsafe fn setEnabledFramings( &self, enabled_framings: &NSArray<AVCaptureFraming>, )

Setter for enabledFramings.

This is copied when set.

pub unsafe fn recommendedFraming(&self) -> Option<Retained<AVCaptureFraming>>

The latest recommended framing from the monitor.

While your AVCaptureSession is running, the monitor continuously observes its device’s scene to recommend the best framing. This recommended framing is always one of the values in enabledFramings. This property may return nil if smart framing isn’t supported for the device in its current configuration. Its default value is nil. This property is key-value observable, and when you observe a change, you may respond to the new recommendation by calling AVCaptureDevice/setDynamicAspectRatio:completionHandler: and setting AVCaptureDevice/videoZoomFactor on the associated device in whatever order best matches your animation between old and new framings.

pub unsafe fn startMonitoringWithError(&self) -> Result<(), Retained<NSError>>

Begins monitoring the device’s active scene and making framing recommendations.

• Parameter outError: A pointer to an NSError indicating why startMonitoringWithError: failed, or to a nil NSError on success.
• Returns: true if successful, false if monitoring could not be started.

The monitor’s recommendedFraming is nil when it is not actively running. Call this method to start monitoring. You may start monitoring before or after calling AVCaptureSession/startRunning, and you may stop active monitoring without stopping the capture session by calling stopMonitoring at any time, but you must set enabledFramings before running your capture session so that the monitor is prepared for your desired framing recommendations. While the monitor is running, you may set enabledFramings at any time to change the framing choices the monitor should consider in its recommendations.

pub unsafe fn stopMonitoring(&self)

Stops monitoring the device’s active scene and making framing recommendations.

The monitor’s recommendedFraming is nil when it is not actively running. Call this method to stop actively monitoring the scene and making framing recommendations. You may start monitoring before or after calling AVCaptureSession/startRunning, and may stop active monitoring without stopping the capture session by calling stopMonitoring at any time.

pub unsafe fn isMonitoring(&self) -> bool

Yes when the receiver is actively monitoring.

See startMonitoringWithError: and stopMonitoring.

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<AVCaptureSmartFramingMonitor> for AVCaptureSmartFramingMonitor

fn as_ref(&self) -> &Self

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

impl AsRef<AnyObject> for AVCaptureSmartFramingMonitor

fn as_ref(&self) -> &AnyObject

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

impl AsRef<NSObject> for AVCaptureSmartFramingMonitor

fn as_ref(&self) -> &NSObject

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

impl Borrow<AnyObject> for AVCaptureSmartFramingMonitor

fn borrow(&self) -> &AnyObject

Immutably borrows from an owned value.

impl Borrow<NSObject> for AVCaptureSmartFramingMonitor

fn borrow(&self) -> &NSObject

Immutably borrows from an owned value.

impl ClassType for AVCaptureSmartFramingMonitor

const NAME: &'static str = "AVCaptureSmartFramingMonitor"

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

type Super = NSObject

The superclass of this class.

type ThreadKind = <<AVCaptureSmartFramingMonitor 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 AVCaptureSmartFramingMonitor

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

Formats the value using the given formatter.

impl Deref for AVCaptureSmartFramingMonitor

type Target = NSObject

The resulting type after dereferencing.

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

Dereferences the value.

impl Hash for AVCaptureSmartFramingMonitor

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 AVCaptureSmartFramingMonitor

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

where Self: Sized,

Increment the reference count of the receiver.

impl NSObjectProtocol for AVCaptureSmartFramingMonitor

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 AVCaptureSmartFramingMonitor

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 AVCaptureSmartFramingMonitor

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

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

impl DowncastTarget for AVCaptureSmartFramingMonitor

impl Eq for AVCaptureSmartFramingMonitor