Flutter 40 - Simple Dialog Video Lecture | Flutter: Build beautiful native apps in record time - App Development

everybody's bright welcome to the
fortieth lunch tutorial today we're
going to be going over the simple dialog
which don't let the name fool you it's
anything but simple it's actually a very
powerful and complex piece of code here
so we're going to go over this in detail
first thing we're gonna do is bring up
our live template if you have no idea
what I just did go watch video 35 in
this series alright so import and we are
going to work with a sink so we need the
dart a sink and in here we're going to
modify our state so we want string boy I
cannot spell answer it that's
embarrassing alright so alright we've
got our answer now we're going to
function that sets this where I say void
set answer string value and from here
we're just going to do the sets date
and from here we're going to say the
answer alright so I just put that little
to do there so if you're using this is a
template you would say okay we record it
to a file or send it to a database or
whatever you were working on so we have
our little set answer there now we need
to actually show the dialogue and this
is kind of the meat of the tutorial here
no not numb geez what are you thinking
there I'm gonna do ask user this isn't a
sick call so in here what we need to do
is build a simple switch statement I say
switch and in here I say case oh I
almost forgot
what we need to do is back up just a bit
part of what simple dialogue does is it
actually can take an enum and display it
to the user and get the answer back to
them or get the answer back from them so
we've got our enum here answer so we're
gonna say answer or not yes and then
break and via the
let's just do this side answer through
the magic of copy and paste we are just
going to make a few of these here
all right and you could actually process
it down here in the switches most people
do but they're all just going to call us
that answer because they're all pretty
much going to do the same thing here all
right now that we've got our switch we
need to well switch we need a value to
switch on so what we're going to do is
await the show dialog and it has a build
context in a child and we're gonna
actually pop that over there so we can
see very clearly what's going on so the
context is just going to be the current
context and the child we're going to
show a new simple dialogue and the
simple dialogue it's got a few
properties and what we're going to do is
we're going to say the title and
children so title do you like flutter
and for the children see that's an array
of widgets so we can add literally
anything we want to this we could say
like you know raised button or we could
say text or you know radio or whatever
we want but there is a widget
specifically for this thing and it's a
new simple dialogue option let's get to
simple dialogue option in there and the
simple dialogue option has a non pressed
which we're just going to say null for
now and a child property in the child
we're just going to say
add a couple little you know things in
there and for the unpressed let's do
navigator dot pop and it takes the
context and it takes a dynamic result so
the dynamic result is going to be
answers yes so really what we're doing
is when this is pressed we're going to
pop the navigator under the current
context with that and um value right
there yeah we just grabbed this little
guy and I'm sure there is a much more
streamlined way of doing this but I want
it to be very obvious what this program
is doing expected to find oh they're
completely forgot so much for copy and
paste saving this time and then we have
our maybe
we have the skeptical maybe in there so
just to kind of recap here this function
returns future null which means we're
actually not returning anything
it's a synchronous function it's
asynchronous because the show dialog is
async and we have to wait on that we're
going to switch on the value returned
out of that and what this does is it
takes a num which we have up here and
basically says hey which one of these do
you want so you have simple dialogue
option that has the enum values in it
and you are popping the navigator
meaning pushing that data back
I shouldn't say pushing you're popping
the data back that's the correct way of
saying it all right now what we need to
do is just simply say there's our answer
I say new Ray's button just gonna say
click me and then of course we are just
going to say bangbang and ask the user
now this should work let's bring this up
in our emulator
hmm seems to be taking a long time to
compile these days I really didn't do
anything super complex I wonder if it's
my computer there we go
so we have a you answered blank if we
say click me do you like flutter yes no
maybe and we're gonna say yes because we
love flutter and it says answer yes so
you can see how you can pretty much do
anything you want here now the really
neat thing about this is you can add
other things because it is a where as a
a array of widgets here you can
you're not just constrained to the
simple dialog option you could say
something like I have no idea what to
put there just icons down home or
something like that
hot reload should take care of that and
then we have a home icon at the bottom
here you can put buttons icons whatever
you want it's actually very very
convenient so if you wanted to do like a
radio list group you know see if radios
check from or checkboxes or you know do
you like flutter maybe and then like a
little input field or something like
that you can do all of that it's very
very straightforward so that's it for
this tutorial i'm gonna click yes
because I like flutter thank you for
watching you can find the source code
for this and all of the tutorials out on
my website void realms calm and be sure
to join the void rooms Facebook group I
can't push that enough everybody sends
me emails and questions join the void
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questions out there there's seventeen
hundred other programmers because I'm
not always available that's it thanks
for watching