Android Application Development Tutorial - 99 - Writing Data to File Output Stream Video Lecture | Android Application Development (Mobile App) - Software Development

what's up guys welcome to your 99th
Android's tour of the new boston and
what we're going to do in this tutorial
is learn how to write data through these
file output streams and input streams
and all that nonsense no it's not
nonsense but all that craziness so what
we can do is basically I show you guys
how to open a file through the file name
here and then we closed it within our on
create so that's basically saying hey if
we don't have this file name we're just
going to set it up for the most part and
close it that's all we did in the last
tutorial now what we're going to do is
we're going to get it open it write
something to it and then close it so we
have this file output stream right and
we call it fos and what we're going to
do is again we can just save open
actually let's set up our edit text or a
string first so we're going to say our
string and we're going to call this the
data that we're going to save what we're
going to do is we're going to say again
our edit text which we called shared
data then we're going to say get text
again and to string here and now what we
can do is we're going to write this this
string basically tore file output but we
can do that a few different ways so one
way that we can do it is we can create a
file and we're going to call this file F
and again you have to import file and
then we're going to say is new file name
herbs are a new file within parentheses
we're going to put our a reference or a
file name which again we created a
string called file name and that's kind
of our path that we're saving to so
we're going to say file name like this
so basically we're going right to this
file a few different ways so one way is
or we can write to this output stream a
few different ways like in the last
tutorial I'll show you guys kind of how
to set open it I'm using a file name
string and a kind of context another way
we can do this is actually using a file
that we just set up so we can say our
fos and we're going to say new file
output stream
and within parentheses we're going to
give it a file name instead of a string
in the context again we just hit our
surrounding try and catch that's going
to open it and then we can also do fos
closed and we would write within here
write some data within this line but we
aren't going to actually use this method
I just wanted to kind of show you guys
how you can set up a file according to a
string name and then use just a new
constructor basically that's going to
send it to the file output stream class
we're going to do is we're actually
going to comment out this whole line of
code and I'm sure you guys you know just
ford ford slash two forward slashes and
we can say saving data via file
something like that but that only codes
out one line of code you guys probably
know this if you've done java but we can
also just say forward slash star and
it's going to code out everything until
we do something like another star
forward slash so now it's just going to
comment out this block of code here
since we are actually going to use this
methodology of saving data we're going
to actually kind of use the same type of
setup that we did in the last tutorial
so we're going to just save fos dot I'm
sorry fos equals open file output
and then we give it again the file name
which is a string comma context dot
private mode the most part and we're
good to go we've opened our file output
stream now what we're going to do is
we're going to write some data so what
we're going to say is fos dot right and
as you can see it takes a byte array for
this right method so what we're going to
do now is convert our string that we got
from our edit text into kind of a byte
array so we're going to say our string
name that we want to save which we call
data and then we're just going to hit
dot get bytes and now what we have to do
is say fo s dot close so it's it's this
is basically the concept we need to open
a file output stream we want to write
some data takes a byte array so we're
going to convert our data into that and
then we're just going to close our
stream again now it's given us an error
because it says you know we have to put
this in a try in a catch
so we're just going to hover over and
say surround with try and catch and
we're just going to move this try to
cover pretty much everything and then
we'll just add the extra exceptions that
we need so after we write we want to
close which will shift format delete
that line of code and we are pretty much
done I mean that's basically this
tutorial just basically we learned about
this right method a few different ways
that we can save via you know either
creating a file from a string and then
using file output stream to create that
and
and then also just using the open file
output which takes a string instead of a
file an actual file type variable and we
set the context to private and then we
just surround that with a try and catch
which catches the input-output
exceptions and prints it to the stack
trace so that's pretty much this
tutorial guys and I'll catch you in the
next one we're actually going to learn
how to load the data and we might learn
about the async task class and what
that's good for so I'll catch you guys
then have a good one