Struct AVExtendedNoteOnEvent 

pub struct AVExtendedNoteOnEvent { /* private fields */ }

Available on crate feature AVMusicEvents only.

The event class representing a custom extension of a MIDI note-on.

Using an AVExtendedNoteOnEvent allows an application to trigger a specialized note-on event on one of several Apple audio units which support it. The floating point note and velocity numbers allow optional fractional control of the note’s run-time properties which are modulated by those inputs. In addition, it supports the possibility of an audio unit with more than the standard 16 MIDI channels.

See also Apple’s documentation

Implementations

impl AVExtendedNoteOnEvent

pub unsafe fn initWithMIDINote_velocity_groupID_duration( this: Allocated<Self>, midi_note: c_float, velocity: c_float, group_id: u32, duration: AVMusicTimeStamp, ) -> Retained<Self>

Available on crate feature AVAudioTypes only.

Initialize the event with a midi note, velocity, instrument and group ID, and a duration.

Parameter midiNote: The MIDI velocity represented as a floating point. Range: Destination-dependent, usually 0.0 - 127.0.

Parameter velocity: The MIDI velocity represented as a floating point. Range: Destination-dependent, usually 0.0 - 127.0.

Parameter groupID: An index indicating the AudioUnitElement within the Group Scope which should handle this event (see AudioUnitElement). This normally maps to a channel within the audio unit. Range: normally between 0 and 15, but may be higher if the AVMusicTrack’s destinationAudioUnit supports more channels.

Parameter duration: The duration of this event in AVMusicTimeStamp beats. Range: Any nonnegative number.

pub unsafe fn initWithMIDINote_velocity_instrumentID_groupID_duration( this: Allocated<Self>, midi_note: c_float, velocity: c_float, instrument_id: u32, group_id: u32, duration: AVMusicTimeStamp, ) -> Retained<Self>

Available on crate feature AVAudioTypes only.

Initialize the event with a midi note, velocity, instrument and group ID, and a duration.

This initializer is identical to initWithMIDINote:velocity:groupID:duration with the addition of an instrumentID parameter which will allow for the possibility of an externally-created custom instrument. If this initializer is used, instrumentID should be set to AVExtendedNoteOnEventDefaultInstrument for now.

pub unsafe fn midiNote(&self) -> c_float

The MIDI note number represented as a floating point. If the instrument within the AVMusicTrack’s destinationAudioUnit supports fractional values, this may be used to generate arbitrary macro- and micro-tunings. Range: Destination-dependent, usually 0.0 - 127.0.

pub unsafe fn setMidiNote(&self, midi_note: c_float)

Setter for midiNote.

pub unsafe fn velocity(&self) -> c_float

The MIDI velocity represented as a floating point. If the instrument within the AVMusicTrack’s destinationAudioUnit supports fractional values, this may be used to generate very precise changes in gain, etc. Range: Destination-dependent, usually 0.0 - 127.0.

pub unsafe fn setVelocity(&self, velocity: c_float)

Setter for velocity.

pub unsafe fn instrumentID(&self) -> u32

This should be set to AVExtendedNoteOnEventDefaultInstrument.

pub unsafe fn setInstrumentID(&self, instrument_id: u32)

Setter for instrumentID.

pub unsafe fn groupID(&self) -> u32

This represents the audio unit channel (i.e., Group Scope) which should handle this event. Range: normally between 0 and 15, but may be higher if the AVMusicTrack’s destinationAudioUnit supports more channels.

pub unsafe fn setGroupID(&self, group_id: u32)

Setter for groupID.

pub unsafe fn duration(&self) -> AVMusicTimeStamp

Available on crate feature AVAudioTypes only.

The duration of this event in AVMusicTimeStamp beats. Range: Any nonnegative number.

pub unsafe fn setDuration(&self, duration: AVMusicTimeStamp)

Available on crate feature AVAudioTypes only.

Setter for duration.

impl AVExtendedNoteOnEvent

Methods declared on superclass NSObject.

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

pub unsafe fn new() -> 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

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<AVExtendedNoteOnEvent> for AVExtendedNoteOnEvent

fn as_ref(&self) -> &Self

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

impl AsRef<AVMusicEvent> for AVExtendedNoteOnEvent

fn as_ref(&self) -> &AVMusicEvent

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

impl AsRef<AnyObject> for AVExtendedNoteOnEvent

fn as_ref(&self) -> &AnyObject

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

impl AsRef<NSObject> for AVExtendedNoteOnEvent

fn as_ref(&self) -> &NSObject

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

impl Borrow<AVMusicEvent> for AVExtendedNoteOnEvent

fn borrow(&self) -> &AVMusicEvent

Immutably borrows from an owned value.

impl Borrow<AnyObject> for AVExtendedNoteOnEvent

fn borrow(&self) -> &AnyObject

Immutably borrows from an owned value.

impl Borrow<NSObject> for AVExtendedNoteOnEvent

fn borrow(&self) -> &NSObject

Immutably borrows from an owned value.

impl ClassType for AVExtendedNoteOnEvent

const NAME: &'static str = "AVExtendedNoteOnEvent"

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

type Super = AVMusicEvent

The superclass of this class.

type ThreadKind = <<AVExtendedNoteOnEvent 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 AVExtendedNoteOnEvent

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

Formats the value using the given formatter.

impl Deref for AVExtendedNoteOnEvent

type Target = AVMusicEvent

The resulting type after dereferencing.

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

Dereferences the value.

impl Hash for AVExtendedNoteOnEvent

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 AVExtendedNoteOnEvent

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

where Self: Sized,

Increment the reference count of the receiver.

impl NSObjectProtocol for AVExtendedNoteOnEvent

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 AVExtendedNoteOnEvent

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 AVExtendedNoteOnEvent

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

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

impl DowncastTarget for AVExtendedNoteOnEvent

impl Eq for AVExtendedNoteOnEvent