No flooring company recommends any kind of wooden floor in a bathroom, and even fewer (fewer than no?) who would recommend it in a basement bathroom where you might not only have water constantly spilling from the top but maybe moisture coming up from the floor.
You want to do it anyway? OK, here are some precautions that will give it a fighting chance to survive an environment that is considered hostile to wood based flooring products.
Understand that 'engineered floating flooring' can handle moisture better than 'laminate floating flooring'. The engineered flooring has a plywood base with a real wood veneer and is more stable. The laminate flooring has a composite wood fibre base and a photographic plastic veneer finish -- at least some of them have water resistant materials in or on the masonite base. But if water does get into the base, it simply swells up and delaminates the top layer.
Let's really separate the flooring from the concrete, not just the standard pad shown in the photo above, but a real separation and drainage layer like Delta FL.
Then as you glue the panels together you must do an absolutely complete job with waterproof polyvinyl glue, to make sure that water does not get below the veneer to the base. If you are not using a self-locking type of flooring, you need to be sure that the edges are tight together until the glue dries. If you don't have flooring clamps to keep them tight together, at least use Blue 3M Painter's Tape. It holds well but releases well also. Finish off the job with silicone caulking all around the edge to prevent any spilled water from flowing under the quarter round and under the flooring.
One laminate flooring company has come out with a special product called Quick-Guard that is not a glue but a gasket, designed to make the floor waterproof but still allow for removing the flooring some day and re-using it elsewhere.
These things will give it a chance, but no-one will give you a guarnatee for a basement bathroom.