There is no indication as to how the floor class is actually used. Where is the floor object created, for example?
You should be testing the result of "loadFromFile()" to see if there are any errors. It could be failing to find the file.
I think you have to pass a reference to Texture instead of pointer, or it won't be working correct.
sprite.setTexture(*texture);
*texture here is not a pointer.
texture is a pointer and
*texture is the deferenced pointer (the actual object i.e. the texture)
Comments:There are better options than using raw pointers with "new". Using objects on the stack can work just fine without the need to use the heap. However, if you need to use the heap, consider reading
this short article. That said, if you store your resources in an std::vector (or similar), they are automatically stored in the heap/dynamic memory.
You don't seem to need the sprite parameter in LoadSpriteIntoStack() as it's an empty sprite and it creates a new copy anyway. Just declare a new sprite in the function (or push/emplace one directly to the vector and set the texture afterwards).
If you're using C++11 or later (and why wouldn't you be doing so?), the loop to draw the sprite stack can be simplified:
for (auto& sprite : stackOfSprites)
window.draw(sprite);
(although you can add braces around that one statement if you prefer)