Indicates whether the receiver is tracking work that can be cancelled.
- iOS 7.0+
- macOS 10.9+
- Mac Catalyst 13.0+Beta
- tvOS 9.0+
- watchOS 2.0+
NSProgress objects are cancellable.
You typically use this property to communicate whether controls for canceling should appear in a progress reporting user interface.
NSProgress itself does not do anything with this property other than help pass the value from progress reporters to progress observers.
NSProgress is cancellable, you should implement the ability to cancel progress either by setting a block for the
cancellation property, or by polling the
cancelled property periodically while performing the relevant work.
It is valid for the value of this property to change during the lifetime of an
NSProgress object. By default,
NSProgress is KVO-compliant for this property, sending notifications on the same thread that updates the property.