Change all floor tiles or walls simultaneously

I often like to have my dungeons with the same floor and wall type. I can change the inside/outside walls of a room, but only one room at a time. It would be great if I could simply change ALL rooms (inside and out, or inside/outside only) with one click, rather than having to do each room on its own. Ditto, changing all floortiles in the dungeon to the same type with one click would be great.