Recording Audio! (Swift in Xcode) Video Lecture | Swift in Xcode: The Complete iOS Development Guide - App Development

hey what's going on everybody today I'm
going to show you how to record and play
audio with Swift and Xcode so let's go
ahead and get started so you just press
record and that starts recording my
voice I say stop it stops the recording
and then using play and that starts
recording my voice I say stay like so
alright so first thing we're going to do
is open up Xcode create a new Xcode
project and this will be a single View
application although this does apply to
everything else click Next
our product name I'm just going to call
this recorder you can of course call
this whatever you want our language will
be such a swift and our devices will be
set to universal click Next and create
alright so first thing we need to do is
head over to our main dot storyboard and
right in here we're actually going to
add as soon as my computer loads it up
we are going to add the buttons that say
record and play so first I'm going to
make this a bit bigger head over to my
buttons right down here so go right down
here add a button right over here and
also a button right over there like so
so this first button will be record and
the second button will be play so we're
going to play the recorded audio from
this button I'm making this slightly
wider so we can change text in it later
but you don't really have to worry about
that let's go ahead open up the
assistant editor and now in the
assistant editor I'm going to right
click or control click and drag from my
record button over to my
viewcontroller.swift and I'm just going
to add an outlet so I'm going to call
this my record
BTN you can of course call this whatever
you want connect and then we also ever
play button so right-click or control
click and drag from our play button over
to our view controller dot Swift and
this will be our play BTN connect and
now we have outlets for our play button
and our record button and now also with
these buttons right here we also add
some actions so with this record button
we're going to right click or control
click and drag over to our view
controller dot Swift and we're going to
insert a connection and this will be in
action the name of this action I will
call this record we are going to start
recording as soon as this action is
called and now we also need to
right-click or control click and drag
from this play button over to our view
controller dot Swift change the
connection type to an action and this
will be our play
so now when this button is pressed we
want to play sound now that's everything
we need to do with the connections
so let's actually close that up head
over to our viewcontroller.swift now and
now inside of this we need to set up our
a/b player or our a/b audio recorder so
in here we're going to say import ad
foundation so we're pretty much going to
import everything that handles sound
with our device and then we're going to
go over to the class here and then right
after our uiviewcontroller we go comma
AV audio player delegates so now this is
going to allow us to delegate the player
on our device to play the audio and then
we also need our AV audio recorder
delegate like so and now we'll be able
to control our recorder and our player
now we just need to apply some variables
to these so let's go right down here and
we're going to save our sound recorder
will be equal to AV audio recorder open
parentheses close parentheses and now we
have our sound recorder that we again
can apply when we say way if we click
record now we can apply some variables
on to that sound recorder and that will
allow us to record that sound and now we
need a variable that handles the sound
being played so we're going to save our
sound player will be equal to and this
is going to be an AV audio player like
so and then open parentheses close
parentheses now first thing we're going
to do is create a new function right
down here and this is basically going to
allow us to set up everything all the
variables that are inside of our
recorder so we're going to save func and
this will be set up recorder like so and
then open parentheses close parentheses
open curly bracket enter close curly
bracket and inside of this we're going
to go var record settings will be equal
to and then this is open square bracket
close square bracket so inside of this
we're going to have all our settings
built into an array so what do we want
in our array well first we want an a B
format ID key and this will be equal to
a K audio format Apple Lossless
right here so we're going to have
lossless audio as our format and if
you're familiar with how audio actually
works
we need to have an encoder a bid rate a
sample rate and the number of channels
so we're also going to add this into our
record settings and I'm actually going
to change the variable name to settings
like so so right in here we're going to
write after this comma let's just go
ahead and click enter tab all that in
that way we get a bit more separated and
I'm going to say AV encoder audio
quality key and then this will be a
colon and then this will be equal to an
AV audio quality dot max dot raw value
so we're having the raw value and this
is going to be our audio quality we're
grabbing the max quality from our audio
then after that you put a comma enter
and now inside of this we're going to
encode our audio with a bitrate key so
we're going to say AV encode bitrate key
and then after this you do a colon and
our bitrate will be equal to 320
kilobits per second so 320,000 now Apple
actually sells iTunes music at 256
kilobits per second so you could make
that at that but I'm going to stick with
320,000 which is what Spotify does and
other things like that now after this at
a comma and we need to say a V a number
of channels key and then we need a colon
and this will be equal to two we have
two channels total and then lastly we do
a V sample rate key and then colon and
this will be equal to 44,000 100.0 if
you want to look into a lot of these
numbers go ahead look it up but I can't
really explain everything to you so
we're going to continue on and also just
make sure there's a space between the 0
and the bracket here now that we have
all those recording settings filled in
we're going to go down here and we're
going to say VAR air and this will be an
NS air like so so if we have an air this
will let us know if we have an error and
will test accordingly if we have that
error now after this we also need to say
sound recorder will be equal to AV audio
recorder and then open parenthesis and
this will be of a URL settings and error
now our URL we're actually going to add
another function in order to get this
URL so I'm going to go down here and say
func
get file URL open parentheses close
parentheses open curly bracket enter
close curly bracket and right after the
get file URL open parentheses close
parentheses we want a return value of an
nsurl so we're going to add an arrow
like so and then nsurl so we're
expecting a URL to be returned now the
file URL that we want to grab is left
path will be equal to and actually we
need to create another function for us
to grab exactly where this path is so
we're going to say func and get cache
directory like so and then we want to
return value of a string so I'm going to
add an arrow and then string like so
then after that you go open curly
bracket enter close curly bracket and
now we're going to grab some paths so
these paths are basically where our
audio file would be held so we're going
to say let paths equal ns search path
for directories in domains and in this
domain will be an NS search path
directory like so dot document directory
so we want to search through the
documents that are inside of our
application and then our domain mask
will be equal to an NS search domain
mask like so dot user domain mask like
so expand tilde we're just going to
equal true then after this we're going
to say as an array of strings like so so
this is an array of strings that we just
created and now we're going to return a
string value to the string that we have
right here so we're going to say return
paths open square bracket close bracket
0 like so so we're grabbing the first
path that's in there for our audio file
and then inside of our gap file URL
right in here we can say let path equal
and inside of this we can say get cache
directory so we're calling this function
up here again and we're going to say dot
string by appending path component like
so so we're going to grab a string
according to what this path component is
called we're going to grab where this is
stored according to our file name
now we don't exactly have our file name
written down so let's go up here and
we're going to create a new variable so
I'm going to save our file name will be
equal to open quotation mark close
quotation mark and this will be audio
file dot m4a now you can use other
formats but for some reason dot mp3
doesn't exactly work but dot m4a is the
way I'm going right now
so now inside of this let path equal
gate cache directory we can put right
inside of the string our file name like
so and then after this we're going to
say let the file path be equal to and
this is going to be an NS URL open
parenthesis file URL with path and
inside of this we're going to put the
path that we just created so basically
just a roundup exactly what happened
right now we have the get file URL right
here and right off of this we just
created a file path now this file path
is equal to an nsurl
which is based off of us just grabbing
the documents off of the device itself
and then we're finding a path with the
component of our file name and then
we're just applying that path onto our
file path and now we can say return a
value of file path and then we just need
to add an exclamation point right after
that now if we were to head back up to
our setup recorder up here we can say
sound recorder equals ABV audio recorder
our URL will now be equal to our get
file URL like so our settings will be
equal to exactly what we created up here
so just type in record settings and then
we're going to say as and then this will
be equal to an open square bracket close
square bracket and at first we have an
NS object on the left side right here so
we're going to type in NS object and
then colon and this will be any object
on the other side like so and if there's
an error we want to say this is equal to
it ampersand error like so and now we
want to go down here and say if let ere
equal error meaning that there is an
error inside of our programming we want
to print a line so we're going to say NS
log something's wrong like so so now it
knows we have an error and if there is
not an error we want to just say
else open curly bracket enter close
curly bracket and inside of this we want
to say sound recorder delegate will be
equal to self so now our view controller
itself is going to delegate the sound
recording then we're going to say sound
recorder dot prepare to record so now
we're preparing the sound recorder to
record so now we're actually going to
get this thing to start recording so
let's go down here and we're going to go
down to our record and right down here
inside of our function that we created
right down here we want to change this
sender equal to a uibutton
like so now in this we want to say if
our sender dot title label text is equal
equal to and say this is equal to record
like so so if it says record in the text
then we want this to happen like so then
close off the curly bracket so now what
do we want to happen well we want to say
sound recorder record so now we're
actually going to start recording now we
also want to change the text that's on
our UI button so let's go ahead and just
say sender dot set title and then our
title will just be equal to capital sto
P and if we're stopped and then for the
control state and I'm going to just type
in dot normal like so and then we need
to go down here and say play button dot
enabled
and we're gonna set this equal to false
as well since because we're recording we
can't play an audio that's not recorded
so we're going to set that not enabled
anymore now if this is not the case then
we just need to say else open curly
bracket enter close curly bracket and
we're going to say sound recorder dot
stop so we're stopping the recording and
then we're going to say sender dot set
title and we're going to set this equal
to capital R Co D Rd whatever record dot
normal now inside of our buted load we
want to all we want to call this
function setup recorder so we're just
going to put that right inside of my
viewdidload so set up recorder and now
if we were to build around this you will
see that I am getting this error so it's
a sound recorder equals a B audio
recorder and then this is exception of
bad access now the cause of this is
actually because my sound recorder would
be equal to and we want this to be equal
to
optional value so I'm going to save our
sound recorder :
av audio recorder and then exclamation
point like so and we want to do this
with our a B audio player as well so :
and exclamation point now if we were to
build around this now we have no more
errors and when we click record we can
record and then we can stop the
recording now as you can see play is not
being activated again and we also need
to work on a few more things so let's
head back over to our project now inside
of this record a button right here we're
also going to go into this else
statement and say play button dot
enabled and we're going to set this
equal to false like so now with our play
sound we also want to play the sound so
instead of my play sound I'm also going
to change the sender equal to a UI
button like so and then right in here we
also want to add a few if statements so
say if the sender dot title label dot
text will be equal to or is equal equal
to Oh publication my close quotation
mark capital PLA Y for play and then we
want to have an open curly bracket enter
close curly bracket like so in this we
want our record button dot enabled equal
equal to false we don't want to record
while we're playing our audio and then
we want to say sender dot set title and
we're going to set this equal to open
quotation mark close quotation mark stop
and then for our four-state we're going
to just say dot normal like so so as
soon as we click this button we're going
to disable our record but we're going to
change our play button to stop and now
down here we want to prepare a player
but first we need to create a new
function so let's go right down here and
this will be an audio player this will
prepare the player to play our recorded
audio so we're going to save our prepare
player and then open parentheses close
parentheses open curly bracket enter
close curly bracket like so I'm sorry
this should be foam cannot far I don't
know why I type that in and it also
looks like I have added one to many of
the closing curly brackets now inside of
our prepared player here first thing
we're just going to add is sound player
will be equal to an a/v audio
layer like so open parentheses contents
of URL and this URL will be equal to our
get file URL so as you can see adding
those functions make it a lot easier for
us to do things later on now this error
I'm going to just put ampersand err so
if there is an error we'll know about it
then down here we're going to say if let
err equal error like so then we just
want to say open curly bracket enter
close curly bracket and you can really
just put whatever you want it's going to
be an NS log for me open quotation mark
close quotation mark bunch of gibberish
it really doesn't matter what I put in
here I just know there's going to be an
error and also I forgot to put up here
we need to create a new variable and
this will be var err : NS error and then
a question mark now again after this if
statement right here we want to put an
else statement and this is basically
everything's running smoothly so we want
to say sound player delegate will be
equal to self like so and then we want
to say sound player dot prepare to play
and then lastly sound player dot volume
and you can set this whatever you to
whatever you want I'm going to make mine
equal to one point zero like so now
let's head back up to our play sound
function right up here and we're just
going to type in prepare player like so
so we're calling this function right
down here from this button and now
lastly we just need to say sound player
dot play like so now there's also an
else statement in this so right after
the if statement we want to say open
curly bracket enter close curly bracket
and we're going to say sound player dot
stop so once our title of our button
that we're clicking is stopped we want
to say sound player dot stop then we're
going to say sender dot set title and
Reena set the title equal to open coach
each my closed quotation mark and this
will be equal to play so we're setting
it back to its normal state and then
we're going to say dot normal like so
now if we were to build and run this we
shall finally have our recorder working
and running so let's say record now as
you can see I click stop but my play
button didn't actually come online again
so let's go over here and I'm going to
say and right down here I want to say
audio recorder did
finish recording and inside of this
we're just going to quickly say play
button dot enabled and we're going to
set this equal to true and now I also
want to say audio player audio player
did finish playing then we also want to
say our record button dot enabled and we
will set this equal to true as well
build and run now one thing you'll
notice this phase if I press record
right now I hit stop I hit play and then
as you will see the stop doesn't go back
to play again so I have to click stop
and then play to hear my recording again
so let's add back over to our project
and go to the audio player did finish
playing function right down here and I'm
just going to say play button set title
and we're going to set the title equal
to open quotation mark close quotation
mark play and then for the state dot
normal like so then close that off
building a run and there you have it I
hit record like so stop play and then it
goes back to normal as soon as the audio
is finished playing thank you all so
much for watching if you enjoyed this
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in the next one