Potty training on a leash

I've heard that a lot of dogs don't like being close to you when they're doing their business.  It was suggested to me before to try out a retractable leash so that the dog can get a distance away from you to go comfortably.  >o.o<  Might work.

Dom, as long as your dog isn't a *puller* on leash, a retractable could be a good solution for you.  I think the shortest one pulls out to about 16 ft. so that could let your dog *hide* while she does her business.

Joyce & Max

If you don't like retractable leads you can look at walmart or any petstore for a training lead that come in very lengths of 15ft, 20ft, or 30ft. I let Blue use this lead for potty time and playing outside. It can also be used as a drag line too if you wish.

Shoot -- get a clothesline and MAKE one -- attach an old leash clip.  Tie it to your belt and keep it looped in your hand.  It's easy to teach them "come" and other commands from a distance too.
 
If you find a poop accident in the apartment, pick it up in paper towel and take it outside and 'put it' somewhere near where you walk her -- just put it somewhere no one will step on it and go get her on leash and take her RIGHT TO IT and *show* her you moved it outside!
 
But that long leash will be fine -- let her have some privacy but even if you have to carry a mirror iwth you WATCH HER ... then the first time you catch her pooping PRAISE the daylights out of her.
 
Psst -- do NOT treat for housetraining -- or you will get them pooping and peeing INSIDE in front of you just to get a treat!!  Keep it direct praise and you'll do better.
 
Reluctance to go on leash usually comes from some idiot having a hissy fit when they SEE the dog going (usually when they are inside).  They over-react (or do something punishing) and the dog makes a strong mental note "NEVER GO IN FRONT OF A HUMAN!"
 
You will do better if you wait until you know it's a typical time to go -- like after eating or after you first get home.  You will only have to move the poop once -- and do pick it up when you go back outside again -- but she won't forget the lesson. 
 
One you 'catch' her going a couple of times and show her how GREAT you think it is -- she will be easier with it!

she will not poo when she's attached to the leash

 
One of two things has likely happened.  First, a human might have yelled at her for pooping indoors.  Instead of learning to poop outdoors, she simply learned not to poop in front of humans.  So, it has nothing to do with the leash, only with your presence.
The way to get around that is to tether her to you so that she can't have any freedom in the house.  Sooner or later she will have to poop, and you can take her outside to do it.  Never scold her for mistakes, and be sure to always have a pocket full of Cheerios so you can dole out 5-6 of them when she does her duty outside.
Using the clicker is a super idea.  The key is in the supervision aspect.  She just can't have any freedom until she's reliable about not pee'ing or pooping indoors.

Psst -- do NOT treat for housetraining -- or you will get them pooping and peeing INSIDE in front of you just to get a treat!! Keep it direct praise and you'll do better.

 
This is one time (there aren't many) when I am going to disagree.  Dogs tend to learn contextually, so the "mental picture" they have when treated outdoors is not the same as indoors.  However, it is important to wait until they have completed the act of pooping before giving the treat.  Giving the treat while the dog is pooping tends to make them retain it, so they end up having to do the rest indoors, and the human believes they are doing it for the treat.
The occasional dog might make the wrong association, but I have not seen that happening but once in a blue moon.