Objective-C Tutorial - Lesson 2: Part 3: Display Information in the Console with NSLog Video Lecture | Learn and Understand: Objective C (English) - Web Development

I need to open up Xcode you'll find
Xcode under Macintosh hard drive then
developer then applications and then
they have all the development tools then
open up Xcode hit create new project and
that under application select command
line tool and it choose and I'm just
gonna name it first underscore program
now I'm gonna save it to my desktop and
hits it okay yeah once you have it all
opened up go to source then first
program dot M now you can delete
everything from the braces to up until
return and then here we go because
that's all just memory management
now we're gonna initialize a few
variables first we're going to
initialize um they're all gonna be in
starter they're all gonna be integers so
int a semicolon and B semicolon and int
C semicolon now we're gonna assign some
variables a is 1 semicolon B is 2
semicolon and C is a plus B
and then you can save that now we're
gonna head back to the PowerPoint to
learn how we will display this data NS
log this is what will let us display
data in the debugger because right now
we're not gonna be making an entire
program we're just gonna be outputting
the all the information whatever we need
to output is just gonna be text in the
debugger you're not sure what the
debugger is you'll know once we go back
and Xcode now strength for matters we'll
need this to export the information to
the e bugger now first you'll need NS
log and then you'll need to put
parentheses then at quotation marks then
this is whatever you want so right now
we're gonna do a modulo B equals and
then this is the formatting part if it's
an integer which ours is its percentage
sign I if it's unsigned integer its
percent you double percent F and a
decimal number its percent to D if it's
like a two decimals two numbers behind
the decimal or 4d or 5d you get the
point
now since art isn't it's regular in
shirts percent i and close off with
quotation marks then comma then the
variable that will be substituted in for
percent I and I'll be C then close the
parentheses and then semicolon then down
below we can see right there what C is
equal to now if you want to display
modulo you have to use two percent signs
that's because all the string four
matters use a percent sign so if you
just use one percent sign
it'll confuse the compiler about what
you want so if you want to use if you
want to
just display a % in the debugger you
have to use 2 for more on string
specifiers go to developer.apple.com
then search string format specifiers and
then click on iphone dev center or the
Mac dead center now there's lots of them
for all the different types of variables
so if you want to look at that you can
but it's not necessary now we'll head
back to Xcode to finish up the program
and finish up this tutorial now that we
know how to export things we want to
display and put it into the debugger all
we have to do is put in that code so
we'll start with NS log and you'll come
up with you'll notice that it comes up
with a suggestion and it's kind of
dimmed out umm Xcode is a very smart
source code editor not all source code
editors have that functionality but if
you if the suggestion is correct just
hit enter in this case it takes us
inside the parentheses now we need to
put at quotation mark and then this is
just whatever is displayed and I'll put
a plus B equals and now we need our
strength modifier that is the % and then
it's an integer that we're going to be
displaying so it's eye then you close it
off the quotation marks then put a comma
and then we'll put the variable name of
whatever will go inside that string
modifier will go in the place of it so
and that is C and
and go notice that whenever you close
off something when you close off the
parenthesis the first one pops up in
yellow so that's another nice feature of
X good then close it off with a
semicolon now we're gonna do another
statement at quotation mark then a plus
B equals percent I close it off comma
you can also do inside inside the NS log
functionality you can actually add
things so we can do a plus B and then
semicolon to end it now NS log at
quotation mark a is and then % I
and quotation marks comma and then hey
so just so we'll know that a equals one
so it'll display that so really actually
I'll just put an equal sign here and
then an S log B equals and percent I
closed off quotation mark comma B then
semicolon so there you have it we've
done all our code all we do is build and
run it now
now before we build and run it there's
actually something that I forgot this is
truly gonna be your first program you
have to add in something NS log at and
just simply put hello world okay this is
gonna be your first program you have to
have that in there because I mean that's
every program is first program
practically okay now we can hit build
and run then hit save all and I have it
so it automatically opens up the bugger
I'll show you how to get that option
turned on in a video that I'll do
upcoming now in your case that a bugger
probably won't come up so what you need
to do is go to run and then actually go
down to console because the console is
what it's actually being exported in I
was saying debugger and it's actually
just part of the bugger so it's the
debugger console and then there you see
the result right there um you see hello
world that we displayed first then a
plus B equals 3 then a plus B equals 3
again and remember we used a and B as a
substitute into that string formatter so
we were at so we see the arithmetic
right in the NS log works perfectly fun
um then a equals 1 and B equals 2 so
there you have it you've just created
your very own program so you are a
programmer programming isn't this huge
monster that everybody thinks it is it
does take time and really just have to
have the will to learn but yeah there
you go congratulations if you have any
questions email me at Mac and computer
help and if these tutorials helps you
out please please please subscribe
thanks for watching
now your homework is just to change what
a and B are equal to change that to
maybe some different numbers maybe add
some more variables change the text and
a slog you know just kind of play around
get familiar with exporting things to
debugger things like that and that's
pretty much it