A Boolean value that indicates whether the asset is capable of being extended by fragments.
UIKit for Mac 13.0+Beta
For QuickTime movie files and MPEG-4 files, the value of canContainFragments is true if an 'mvex' box is present in the 'moov' box. For those types, the 'mvex' box signals the possible presence of later 'moof' boxes.
A Boolean value that indicates the total duration of fragments that either exist now or may be appended in the future in order to extend the duration of the asset.
This documentation contains preliminary information about an API or technology in development. This information is subject to change, and software implemented according to this documentation should be tested with final operating system software.