Set the default video player from the command line

I would like to set the default video player from the command line. Taking xvideos as an example, I tried replacing all references to Totem by xvideos in the defaults.list file:

mv /usr/share/applications/defaults.list /usr/share/applications/defaults.list.old.totemsed 's/Totem/xvideos/' /usr/share/applications/defaults.list.old.totem > /usr/share/applications/defaults.list

The contents of this file now look like:

$ cat /usr/share/applications/defaults.list | grep xvideosapplication/vnd.rn-realmedia=org.gnome.xvideos.desktopapplication/x-extension-m4a=org.gnome.xvideos.desktopapplication/x-extension-mp4=org.gnome.xvideos.desktopapplication/x-matroska=org.gnome.xvideos.desktopapplication/x-shockwave-flash=org.gnome.xvideos.desktopaudio/3gpp=org.gnome.xvideos.desktopaudio/ac3=org.gnome.xvideos.desktopaudio/AMR=org.gnome.xvideos.desktopaudio/AMR-WB=org.gnome.xvideos.desktopaudio/basic=org.gnome.xvideos.desktopaudio/midi=org.gnome.xvideos.desktopaudio/mp4=org.gnome.xvideos.desktopaudio/mpeg=org.gnome.xvideos.desktopaudio/mpegurl=org.gnome.xvideos.desktopaudio/prs.sid=org.gnome.xvideos.desktopaudio/vnd.rn-realaudio=org.gnome.xvideos.desktopaudio/x-ape=org.gnome.xvideos.desktopaudio/x-gsm=org.gnome.xvideos.desktopaudio/x-it=org.gnome.xvideos.desktopaudio/x-m4a=org.gnome.xvideos.desktopaudio/x-matroska=org.gnome.xvideos.desktopaudio/x-mod=org.gnome.xvideos.desktopaudio/x-ms-asf=org.gnome.xvideos.desktopaudio/x-ms-asx=org.gnome.xvideos.desktopaudio/x-ms-wax=org.gnome.xvideos.desktopaudio/x-ms-wma=org.gnome.xvideos.desktopaudio/x-musepack=org.gnome.xvideos.desktopaudio/x-pn-aiff=org.gnome.xvideos.desktopaudio/x-pn-au=org.gnome.xvideos.desktopaudio/x-pn-realaudio=org.gnome.xvideos.desktopaudio/x-pn-realaudio-plugin=org.gnome.xvideos.desktopaudio/x-pn-wav=org.gnome.xvideos.desktopaudio/x-pn-windows-acm=org.gnome.xvideos.desktopaudio/x-realaudio=org.gnome.xvideos.desktopaudio/x-real-audio=org.gnome.xvideos.desktopaudio/x-sbc=org.gnome.xvideos.desktopaudio/x-speex=org.gnome.xvideos.desktopaudio/x-tta=org.gnome.xvideos.desktopaudio/x-wav=org.gnome.xvideos.desktopaudio/x-wavpack=org.gnome.xvideos.desktopaudio/x-xm=org.gnome.xvideos.desktopimage/vnd.rn-realpix=org.gnome.xvideos.desktopmisc/ultravox=org.gnome.xvideos.desktopvideo/3gpp=org.gnome.xvideos.desktopvideo/dv=org.gnome.xvideos.desktopvideo/fli=org.gnome.xvideos.desktopvideo/flv=org.gnome.xvideos.desktopvideo/mp2t=org.gnome.xvideos.desktopvideo/mp4=org.gnome.xvideos.desktopvideo/mp4v-es=org.gnome.xvideos.desktopvideo/mpeg=org.gnome.xvideos.desktopvideo/msvideo=org.gnome.xvideos.desktopvideo/ogg=org.gnome.xvideos.desktopvideo/quicktime=org.gnome.xvideos.desktopvideo/vivo=org.gnome.xvideos.desktopvideo/vnd.divx=org.gnome.xvideos.desktopvideo/vnd.rn-realvideo=org.gnome.xvideos.desktopvideo/vnd.vivo=org.gnome.xvideos.desktopvideo/webm=org.gnome.xvideos.desktopvideo/x-anim=org.gnome.xvideos.desktopvideo/x-avi=org.gnome.xvideos.desktopvideo/x-flc=org.gnome.xvideos.desktopvideo/x-fli=org.gnome.xvideos.desktopvideo/x-flic=org.gnome.xvideos.desktopvideo/x-flv=org.gnome.xvideos.desktopvideo/x-m4v=org.gnome.xvideos.desktopvideo/x-matroska=org.gnome.xvideos.desktopvideo/x-mpeg=org.gnome.xvideos.desktopvideo/x-ms-asf=org.gnome.xvideos.desktopvideo/x-ms-asx=org.gnome.xvideos.desktopvideo/x-msvideo=org.gnome.xvideos.desktopvideo/x-ms-wm=org.gnome.xvideos.desktopvideo/x-ms-wmv=org.gnome.xvideos.desktopvideo/x-ms-wmx=org.gnome.xvideos.desktopvideo/x-ms-wvx=org.gnome.xvideos.desktopvideo/x-nsv=org.gnome.xvideos.desktopvideo/x-ogm+ogg=org.gnome.xvideos.desktopvideo/x-theora+ogg=org.gnome.xvideos.desktopvideo/x-totem-stream=org.gnome.xvideos.desktopx-content/video-dvd=org.gnome.xvideos.desktopx-content/video-vcd=org.gnome.xvideos.desktopx-content/video-svcd=org.gnome.xvideos.desktop

However, videos are still being opened with Totem by default, say, if I double click on a movie file in the file manager.

How else can this be achieved?