Android Application Development Tutorial - 68 - Setting up Animation Thread

what's up guys welcome to your 68
Android tutorial for the new boss in
again with me Travis and we're still
working with the surface for you Matt
for a few more tutorials here but let's
just quickly talk about what we're we're
doing here what the surface view is all
about because again the view takes up
too much processing we don't want that
basically what we're doing is we're
grabbing the surface from a view and
instead of doing that loop from the when
we worked with the extending the view
and we just invalidate it it so I'd go
through again and again and it'd be
invalid every time we're gonna set up
our own thread that's going to handle
the the animation and and you know that
good stuff so that's what we that's why
we implemented the runnable because
again when we implement runnable that
same is kind of like a thread and
whatever our threads gonna do it's
within this runnable method or within
this run method so let's get this set up
here first thing we want to do is change
your constructor you can delete the
comment or not that's up to you what we
need to pass in to the super the context
I'll get rid of that air that we're
getting there again or whatever you guys
typed here that's what you're gonna pass
in just leading some of those those
things I just wanted tested test how
long this would take to explain so uh
there we go we set that up now what we
want to do is we want to kind of want to
create it a holder because we have the
surface of a view and basically what a
surface holder is is it helps us manage
that surface because it's like a crazy
young stallion thats just bucking around
and the surface holders like Oh settle
down there young stallion and else gives
us some helpful methods mainly that's
the reason so let's set this holder up
and we want this holder to be accessible
to our whole class so we're gonna say
surface holder
so tight and we're gonna call this
something like our holder and there we
go
now we just have to import surface
holder class and define it within our
constructor our holder is going to be
equal to get what is it get holder I'm
sorry there we go we set up our holder
already pretty simple
now basically like I said we're using
this thread to animate our canvas so
what we're going to do within this and
basically what the holder does is it can
tell us if the surface is valid because
if it's not valid we aren't going to be
able to paint and create a canvas and
paint to the canvas if the surface is
isn't available or is invalid so that's
one thing that holder can do another
thing the holder is going to do is allow
us to lock the canvas so no other thread
can draw on our canvas without our
permission or just some flukes we're
going to lock the canvas draw to the
canvas and then unlock and display the
canvas for the whole world to see so
that's what we're gonna do within this
thread
but before we do that as you remember
when we set up our our other thread for
our splash we need to start a thread so
what we're going to do is we're gonna
create a thread within you know my bring
back surface class we're gonna call this
our thread because we need to set up a
thread we're just gonna set this equal
to null right at the beginning and then
within the constructor we're gonna
define it so we're gonna say our thread
equals new thread and we're gonna pass
in the context of this so basically it's
gonna say hey we're creating a new
thread but use this run method that's
what this is referring to and then all
we have to do is just kind of start a
thread now because we've defined it so
we're gonna say our thread and then dot
start and that's pretty much it for this
tutorial again it's kind of boring we
didn't go it through anything the next
one is where we're gonna define
everything within a run method but I
just want to get this against
and kind of explain stuff I just wanted
to kind of talk and not do a lot of
coding because it is pretty important to
understand these concepts and what a
holder is and thread and all that good
stuff which will explain even more as we
go on throughout the next couple of
tutorials so I'll catch you guys then
have a good one peace