[ Version ( since = "0.8.0" ) ]
public Cancellable cancellable { get; construct; }
An optional cancellable used to cancel the entire download operation.
If a Cancellable instance isn't provided for this property at construction time (i.e. to DownloadStream), one will be created internally and can be retrieved using get_cancellable and used to cancel the download operation with cancel just as if it was passed to DownloadStream.
If the download operation is cancelled using this Cancellable, any ongoing network activity will be stopped, and any pending or future calls to InputStream API on the DownloadStream will return CANCELLED. Note that the Cancellable objects which can be passed to individual InputStream operations will not cancel the download operation proper if cancelled — they will merely cancel that API call. The only way to cancel the download operation completely is using cancellable.