Android Application Development Tutorial - 155 - StringBuilder and XML

what's up guys welcome to your 150 fifth
Android tutorial for the new boss and
we're gonna learn a little bit more
about the stringbuilder actually not
much more but I'm gonna actually kind of
describe what it does if you guys didn't
pick up on already and we're gonna start
building our XML parser class also go
over an overview of which each class
does so it's again just kind of an
informative tutorial not much learning
but kind of reviewing what we've done so
again we're going to parse some data
from this XML file of the Google Maps or
Google weather API and as you can see
here we have the base URL and then we
have a city and a state
so what we're gonna do is we're gonna
append something to a string builder to
build on our city and our state on to
this URL but first we're gonna copy this
base URL and we're just gonna ctrl copy
the www.google.com
hey I question mark weather equals
that's what we're copying copying we're
gonna go over to our weather XML parsing
class and we're gonna set up this
variable again it's just gonna be string
reference so we're gonna say string and
we're gonna call this base URL we're
gonna set this equal to what we just
pasted within quotations and there we go
make sure you have the HTTP in there
you should have copied over as well but
you know you want that so now we have
our base URL set up again we can just
say something like ecstatic final
because you know the base URL is not
gonna change just the endian is and
again we have our edit text for a city
and our edit text for state we're just
gonna pull that data from the edit text
for city and state within our on click
method pretty simple again nothing new
we're just gonna say string c for city
and we're going to refer to our edit
text which we called city at least i did
and we're gonna say get text
and then dot to string again nothing new
and then we're also going to set up our
state which we're going to call s this
is gonna be our edit text which I called
state and again just get text dot to
string and there we go we have two new
strings for whatever the person entered
in the edit text for the city and
whatever the person entered in the state
edit text
now what we need to do is we need to add
to the string reference you know you
guys priority know how to do that but
some of you might be like how can we add
to a string and we what we use is
something called a string builder which
we have used already but I didn't really
explain it and what a string builder is
is it just allows us to manipulate
strings either add to it or subtract so
if you're like climbing a mountain and
you have a string or a rope you're like
I don't have enough rope you probably
want to use a string builder to you know
add some more string to what you got and
that's pretty much the same way it works
in Java is we use a string builder so
we're just gonna say string builder
we're gonna call this URL we're gonna
set this equal to a new string builder
we gotta give it the initial string that
we want to add to so we're gonna give it
that you know that string we just set up
which was called base URL and there we
go
we have a string builder which is kind
of a new string builder with the base
URL now what we want to do is we want to
add to that base URL the city and the
state and again we have to put a comma
in between as you can see up here
otherwise you know it's not gonna work
so if we had something like that it's
gonna be like I don't know what you're
talking about that's crazy
so we need that comma as well so we're
gonna use a string builder to add the
city add a comma and add the state and
how we do that is by the method append
which we've used as well so we're going
to refer to our string builder which
we've just called URL and we're gonna
say dot append
and what we're gonna do is we're gonna
add to that string so what we're gonna
append which is basically meaning like
addition so we're gonna say we want to
add our city first and we need to add
two plus and then in quotations we're
gonna add our comma pretty simple and
then we also have to add our state as
well so that's s again those are our
string references that we set up
according to our edit text pretty simple
right and then all we can do is we can
set up a new string and we're gonna say
full URL we can just set this equal to
our string builder which we called URL
and then just say two string because
again it's not a string it's a it's a
string builder and we just convert it
into a string now we can refer to this
URL which has our city comma state
attached the end of our base URL so
pretty simple it's not too complicated
of a concept but I thought I'd just talk
about it so you guys understand it a
little bit more thoroughly instead of me
just kind of blathering on because I
know sometimes that gets confusing now
let's quickly just talk about what all
these classes are gonna do before we
actually start programming so you guys
have something to look forward to this
weather XML parsing class this is where
we're gonna set up our XML parser and
you know kind of just set that up and
then what we're gonna do is we need
something to handle something that we're
looking for and what we're looking for
is gonna be handled within this handling
the xml stuff class we're gonna be like
hey i don't care about all the other
junk just give me the city and give me
the temperature in fahrenheit and i'll
be happy so that's what this class is
gonna do but within this class we're
gonna send some data
once we receive like the city name we're
gonna be like okay yes send this data
over to our xml data collected class and
that's just gonna store some stuff and
we're gonna create some methods within
here and it's gonna store city and it's
going to store temperature then we're
gonna create a method like return data
or something collected data maybe
whatever we want to call it right now
who cares but then within our weather
XML parsing class we can call to our
data collected class and just be like
hey return the data that you collected
and so that's how the frame works
basically gonna work for this XML parser
so hopefully you guys have kind of an
understanding of those three classes so
when we set them up your aren't
completely confused like you may have
been you know previously but again
thanks for watching guys and I'll catch
you in the next tutorial hope you have a
good