With my Whites I keep a ceramic bulb on one side of the tank so there is a heat gradient allowing the frogs to choose whether they want to be warm or cooler. As far as light, I am using a LED strip that is designed for aquariums plus whatever indirect sunlight the tank receives from being near the window.

Now, I've not kept tree frogs for very long, only a week or so, but I've noticed that they do prefer to stay on the side the ceramic bulb is located. So I would conclude they will indeed 'bask' where it is warmer.