I you are in a store and placed some items in your bag, but then you were taking them out of the bag and haven't left the store is this considered shoplifting

What state do you reside in?

In many states within the US, yes it is. In some states merely putting them in a bag or purse or pocket is shoplifting, in other states you have to be walking toward the door ( but not out of the door yet)

So if your store arrested you within the store, yes they would be, since if you go to court, and merely say you were in the store and it was not allowed, you would be found not guility