Well, I am late to this "party" but I have been running the gamut on this for the wife, I have used a privacy tent with the porta Potti in it, best solution in my opinion. The urinal bottle with the lady J adapter, works well also, if you can manage the gymnastics to use it. The wife isn't always hip on the privacy tent and it can be a pain to set up when traveling and just staying the night in a camp ground. So, the luggable loo on a 5 gal bucket is a little high for inside, so I found a 3 1/2 gal bucket at Home Depot that is 4" shorter but has the same opening size as a 5 gal bucket and the luggable loo fits, the wife can use it in The trailer if she wants that way. My teardrop is 52" tall inside so makes it a little easier and it's a 5x10, but it could work in a 8' length one also.
I was going to put a tube running through the floor with a 1 1/2" hose and attach the lady J to it and a container underneath the trailer. Much like the relief tube we had in our agency planes when working surveillance for long hours and landing wasn't an option.
I can use the urnal with the screw on lid just fine myself.