Sets the delegate and dispatch queue to use handle callbacks.
- iOS 6.0+
- Mac Catalyst 13.0+
The delegate object to notify when new metadata objects become available. This object must conform to the
Metadata Output Objects Delegate
The dispatch queue on which to execute the delegate’s methods. This queue must be a serial queue to ensure that metadata objects are delivered in the order in which they were received. If the
nil, you may specify
nilfor this parameter too; otherwise, you must specify a valid dispatch queue.
When new metadata objects are captured from the receiver’s connection, they are vended to the delegate object. All delegate methods are executed on the dispatch queue specified in the
objects parameter. To ensure that metadata objects are processed in a timely manner and not dropped, you should specify a dispatch queue dedicated to processing the objects or that is otherwise not busy.