How to access the camera ID when making a video call

[EsmaeeilMoradi]

Hi,
in VectorCallViewActivity class Handel Video call.
how can access the camera in class?
because I use only the front and back camera in video call but when I Clicked on mSwitchRearFrontCameraImageView (ImageView)
called methods :
toggleRearFrontCamera();
and this method cant access the camera Id......