in the past programmers have often
wondered which architectural pattern to
use when designing their apps should
they be using NBC MVP MVM or one of the
other patterns available and in the past
Google refused to make any specific
recommendations the android framework
provided tools that could be used with
any architecture with varying degrees of
difficulty and Google left that up to
developers to use the most suitable
architecture for their apps but with the
recent introduction of architecture
components Google are now suggesting in
architecture and that's mvvm now mvvm
stands for model view viewmodel
and the android framework now includes a
view model class that we can use in our
apps there isn't time to discuss the
various architectural patterns in this
course this is a practical programming
course not a theoretical computer
science course now if you do want to
know more about the various patterns
then the Google search engine as always
is your friend I've got a Wikipedia
article which I'm just going to briefly
bring up on the screen this is a good
starting point for mvvm and the actual
article contains the link to MVC and MVP
if you want to learn more about those
patterns as well so in this section of
the course we're going to introduce the
frameworks view model class and see how
it can make our apps more responsive and
easier to maintain and starting up in
the next video we'll have a look at
androids view model class to get a feel
for what it can do for us
will then convert a couple of our apps
to use a view model we'll start with the
calculator app from a few sections ago
that's a really simple example and makes
it really easy to see where the view
model fits into the overall design
after that we'll then convert the top
ten downloader app to use a view model
to see a more real-world use of view
model in an app and our data base app in
the later section still we'll be using a
view model as well so let's get started
and see what these view models are all
about see you in the next video