I am trying to develop an android application, which is using the Google Cast SDK (v3) to play videos on Chromecast devices. For this I am following the tutorial over at Google Cast Docs, and as of now I am able to play videos on the Chromecast. One of the steps is to extend the ExpandedControllerActivity class to create a playback control sort-of activity. From what it seems, the class should be under the Android.Gms.Cast.Framework.Media.Widget namespace, but I can only find IControlButtonsContainer and MiniControllerFragment under it.
I am not sure whether I am looking at the wrong place or whether this is not implemented at all. If the class is not yet implemented, is there a way that I can implement it myself.