java - How to set videoView inside Fragment in android -

how set videoview inside fragment. pushed a.mp4 file inside file explorer. 3 error shows 1. method findviewbyid(int) undefined type videos. 2. constructor mediacontroller(videos) undefined. 3. create method getwindowmanager(). please me how set videoview inside fragment.

    public class videos extends fragment {     videoview video_player_view;     surfaceview sur_view;     mediacontroller media_controller;     displaymetrics dm;      public videos() {}      @override     public view oncreateview(layoutinflater inflater, viewgroup container,             bundle savedinstancestate) {         view rootview = inflater.inflate(r.layout.frag_videos, container, false);         return rootview;     }      public void getinit() {         video_player_view = (videoview)findviewbyid(r.id.videoview1);         media_controller = new mediacontroller(this);         dm = new displaymetrics();         this.getwindowmanager().getdefaultdisplay().getmetrics(dm);         int height = dm.heightpixels;         int width = dm.heightpixels;         video_player_view.setminimumheight(height);         video_player_view.setminimumwidth(width);         video_player_view.setmediacontroller(media_controller);         video_player_view.setvideopath("/mnt/sdcard/a.mp4");         video_player_view.start();        } }