Struct SHCustomCatalog

Source

pub struct SHCustomCatalog { /* private fields */ }

Available on crate features SHCatalog and SHCustomCatalog only.

Expand description

An object for storing the reference signatures for custom audio recordings and their associated metadata.

Create a custom catalog by adding reference signatures that you generate from audio that you provide. You also add the associated metadata for each signature. Save your custom catalog and share it with others. You can also load a saved catalog.

Implementations§

Source §

impl SHCustomCatalog

Source

pub unsafe fn dataRepresentation(&self) -> Retained<NSData>

The data representation of this file, it can be written to disk

Source

pub unsafe fn addReferenceSignature_representingMediaItems_error( &self, signature: &SHSignature, media_items: &NSArray<SHMediaItem>, ) -> Result<(), Retained<NSError>>

Available on crate features SHMediaItem and SHSignature only.

Adds a reference signature and its associated metadata to a catalog.

Note: This system ignores calls to addReferenceSignature(_:representing:) after adding the catalog to an SHSession.

Parameters:
signature: The reference signature for the audio recording.
mediaItems: The metadata for the recording.

Source

pub unsafe fn addCustomCatalogFromURL_error( &self, custom_catalog_url: &NSURL, ) -> Result<(), Retained<NSError>>

Loads a saved custom catalog from a file.

Parameters:
customCatalogURL: The file URL for a custom catalog.
error: An output value in Objective-C that indicates the type of error; otherwise, nil.

Source

pub unsafe fn writeToURL_error( &self, destination_url: &NSURL, ) -> Result<(), Retained<NSError>>

👎Deprecated: Use dataRepresentation

Saves the custom catalog to a local file.

If destinationURL is a directory, the system creates a Signatures.shazamcatalog file.

Parameters:
destinationURL: A URL for the saved custom catalog file.
error: An output value in Objective-C that indicates the type of error; otherwise, nil.
Returns: YES if the catalog writes to the file; otherwise, NO.

Source

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

Creates a new custom catalog object for storing reference audio signatures and their associated metadata.

Returns: A new custom catalog for storing processed reference audio recordings and their associated metadata.

Source

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

Creates a new custom catalog object for storing reference audio signatures and their associated metadata.

Source

pub unsafe fn initWithDataRepresentation_error( this: Allocated<Self>, data_representation: &NSData, ) -> Result<Retained<Self>, Retained<NSError>>

Load a SHCustomCatalogfrom data

Parameter dataRepresentation: The data representation of the SHCustomCatalog Parameter error: Error populated if not a valid data representation

Methods from Deref<Target = SHCatalog>§

Source

pub unsafe fn minimumQuerySignatureDuration(&self) -> NSTimeInterval

The minimum duration of a query signature that you use to match reference signatures in the catalog.

Source

pub unsafe fn maximumQuerySignatureDuration(&self) -> NSTimeInterval

The maximum duration of a query signature that you use to match reference signatures in the catalog.

Methods from Deref<Target = NSObject>§

Source

pub fn doesNotRecognizeSelector(&self, sel: Sel) -> !

Handle messages the object doesn’t recognize.

See Apple’s documentation for details.

Methods from Deref<Target = AnyObject>§

Source

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());

Source

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.

Source

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`
    }
}