A Boolean value that indicates whether the layer is rendering video frames from its source.
- iOS 13.0+
- Mac Catalyst 13.0+
A preview layer begins previewing when you call the capture session’s
start method. When associated with an
AVCapture, all video preview layers are guaranteed to be previewing by the time the blocking call to
While a session is running, you may enable or disable a video preview layer’s connection to start or stop the flow of video to the layer. You may key-value observe the connection’s
is property to observe this property changing, and synchronize any user interface changes to take place precisely when the video resumes rendering to the video preview layer.