Are Fragments and Fragment Activities inherently faster than Activities?

Question

Are Fragments and Fragment Activities inherently faster than Activities?

If I don't need to load my activity in fragments, should I be using FragmentActivities and Fragments over Activities?

Reason I am asking is because I have been using Activities, exclusively, for years, and the Facebook SDK as well as Google Maps 2.0 have forced me to use Fragments, and I wonder now if they are inherently "better" or not, versus some other implementation.

If this "not constructive" or "too open ended" then obviously the answer is "no". But if there are some Google developer documents or blog on this exact subject, then I would like to be aware of it

Answer 1

I became a believer in Fragments in my last application. Whether or not they are computationally faster, they feel faster because you can swap them in and out basically instantaneously, including full support for the back stack if you do it right (call addToBackStack() on the transaction, or something very similar).

I now use Fragments / Fragment activity for all navigation I want to feel very quick, like clicking on a row to get more details. I only launch new activities for when I want to do a fundamentally different thing and have a clean slate to work with. For instance, I usually have a LoginActivity that deals exclusively with logins/registrations, and at least one more that is the core of the app.

But the fundamental benefit of Fragments still remains their flexibility. I can show fragments on top of other fragments, re-arrange them on different screen sizes, etc. But there are loads of other benefits. It just takes a while to feel natural (just like Activities did at first).

One caveat, I always regret embedding fragments in my layouts. I can't give exact reasons here off the top of my head, but essentially you just lose some flexibility. Instead, I build a normal layout for each fragment, and add a placeholder view in the activity layout, create the fragment programmatically, and use transaction.replace() to add it to the layout. Perhaps because this is the main way I swap fragments in and out of that placeholder view, and prefer to just have a single way of doing things where possible.

Answer 2

yeah, fragments are introduced exclusively for supporting large screens to use the area efficiently.handling fragments is very easy and in terms of memory.but nested fragments makes trouble