Jetpacks For You And I

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I you should all be seeing my my Andres

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video screen here I am just gonna flick

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to my slides because that's what you

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want to see first

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so yeah hello everyone my name is Marcus

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mokona and I serve the developer

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evangelism team at Twilio I have been a

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developer I have been a hundred

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developer for many many years I you know

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I know you know where to find me on the

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Internet

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but I just wanted to make sure there's

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some information about me in here also

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some information about what we do to

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lose a company I work for

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if you don't know Twilio Twilio is a

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communications platform that helps

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developers like you and i to add

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communications into your applications

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such as like text messages chat video

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and anything to do with communications

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here so you've probably used William in

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the past that you don't know if you've

00:56

used something like lyft or uber or

00:58

Airbnb for example it's all using

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Twitter on the back end well that's

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enough about video I wanted to also let

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you know I am an Android EEE and I am

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very very passionate about this thing

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called jetpack which is what I'm gonna

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be telling you about today but I want to

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start like very very slow here and I

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want to start by telling you a story ok

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so this is the story of the year 2017

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and because we're talking about 2017 I

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kind of want to change the slides and

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say this was a long long time ago 2017

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because they're talking about tech years

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ok back in 2017 there was here I was

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writing code just like this so I was

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getting my instance fades just like this

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and I imagine that if I could asked for

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some of you to like raise your hand you

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would say yeah I I see big things this

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way the other thing that I was doing is

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I was also building camera applications

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back then and again if I could ask you

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to raise your hands I'm sure you would

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say yeah I'm building camera

02:06

applications or I used to build some

02:08

camera applications and and like just it

02:12

just kind of gets

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I when it comes to camera applications

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for example I think that you've all

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you've all seen something like this okay

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because building your camera application

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is super easy right now well it used to

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be like super easy it's easier now but

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it used to be super easy because

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building a camera application basically

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means well you create the camera manager

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then you set up the camera ID their new

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sets at the camera but then you set the

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transformation matrix a text review and

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then you start a background threads then

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you open a connection to the camera with

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a given ID and then you set up the image

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buffer size and sex review then you

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start the camera module and then you

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start the camera preview

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that's easy right does anyone else here

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getting my own Society yeah I'm sure if

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you could raise your hand your words

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I'm sure if you could you know doing

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some conference water right now you

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would that's the kind of thing I used to

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deal with okay and then came the ye olde

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2017 so that's you know talking about

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old markers they're going on 2017 when

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everything changed because better Royal

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2017 they announced the architecture

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components so back then architecture

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components was the name of it which

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later just came to be part of the

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jetpack the jetpack funding and I

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remember listening to my clearing back

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then and my time and talks like

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specifically about jetpack sector

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components but he used terms like

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scalability and use terms like life

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cycles and or ends and backwards

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compatibility and like especially on the

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backwards compatibility I remember back

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there and being kinda like this like I

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don't know about this and and so

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basically I did what most people did

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which is nothing I remained skeptical

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and I was like I am NOT gonna adopt this

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thing so good why old 2018 came about

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and 2018 just absolutely changed

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everything for me

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because at Google i/o 2018 they

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announced what be jet tech components

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are like that you know what is what has

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included components and it was really

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interesting because you had stuff like

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architecture components had behavior you

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had UI in foundation and and the premise

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was you could standardize Android

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development so if you use emojis on your

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application for example here's a way for

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you to do emojis if you use fragments

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there's a way for you to do it

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navigation super interesting cuz like

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everyone sorts of like does navigation a

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different way paging and really for

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databases and it's like wow there's

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suddenly there's like one way of doing

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things and I know this if Android pack

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is a new thing for you and and it wasn't

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your thing for me as well I

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you want to start slowly here but you

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not only want to start slowly but today

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if you're not a jet pack fan I am gonna

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turn you into a jet pack fine

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so we're gonna be changing this let's

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start with the basics because I think if

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you've been an Android developer for

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even if you've been an Android developer

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for a week you will have seen something

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like this which is an applications

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lifecycle so we look at how this is this

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is a look of how life cycles actually

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working on tries again you have seen

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this before but if you remember in my

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previous slides we talked about the same

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instance so let's just go back to my

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previous slide where we talked about say

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the sades instance let's say you have an

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application and your your application

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looks like this so you had received

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instance but let's make it a bit more

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real so instead of like saving games

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fades will make it a bit more real and

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we'll turn that into a number generator

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application because that's the kind of

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thing you want to build right if you

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want to go into the Play Store this is

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where the money is you create a number

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generator application and also you know

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notice that it generates a number

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between 1 and 42 which you know there's

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all the numbers you want now we have

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this application we have the methods on

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create and usually if I if I had a if I

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had a regular audience I would say so

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what happens when I turn my phone and

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there's always gonna be someone clever

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in the audience who say well when it's

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on your phone that number changes and

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some people go removing cursor from the

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screen yeah absolutely

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so some people go oh like the number

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changes and and the reason the number

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change is this

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this is expected okay because every

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single time you change the phone this is

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called

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a configuration change so you get your

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phone you've got your phone on your

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hands you get your phone your turn and

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that's a configuration change so every

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single time this would

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it's a new number for you that is

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between one and forty two so already the

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behavior here is slightly different than

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one would expect because one would

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expect okay so when it done my phone

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nothing changes I still get the same

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number but no configuration changes

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calls your phone to change that and

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obviously I will say here like I'll

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leave a caveat here which is I could

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very easily just have done some like

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shenanigans with my codes it says no I'm

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gonna say that fades and then if you

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turn your phone like the number doesn't

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change but I will I will continue and

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say that what is what I've been using

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here is the Safety's and state and for

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the specific case of same things and

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stays the amount of dates it should be

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kept small because the system process

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needs to hold on to the the provider

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data for as long as the user can ever

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navigate back to the activity so let's

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say you had an activity in your head

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like a bunch of navigation there when

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the user returns you still want to keep

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that same number in there so all this is

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kind of like bundled inside the memory

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but there is a recommendation and this

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is a recommendation by Google which says

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you can only store 50k of data so you

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can you can absolutely go over 50k

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Abeyta

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but that's not recommended so if you if

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you want phone google and say hey i'm

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storing 60 k updates and my applications

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crashing or like it's not keeping stays

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mobile say well you're on your own I'm

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sorry because a recommendation is 50 K

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of data now let's let's look at a

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different demo here because hey like

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number generators are great like we all

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love number generators but let's look at

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a real demo and the reason I want to

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show you this real demo is I want to

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show you why this stuff is important so

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I'm gonna bring my cursor back to my

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screen and I'm gonna show some code that

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I've wrote that I've written in here so

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what we have in here is we have a very

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very simple applications for an activity

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it's got a class this is a data class

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with some results and what it does is it

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goes into an external API that's the

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Pokemon API and it gets

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Pokemon information

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I've got my clients in here and what I'm

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doing is like I'm actually debugging

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everything okay so I want to make sure

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that I can see everything my application

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does and to show you I'm not cheating I

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am gonna show you my phone in here which

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hopefully we can get in the right light

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and I am gonna relaunch this application

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and I wanted to see what happens when I

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relaunch so basically it just goes into

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the internet it just goes into pokeo API

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Co and it downloads some data then it

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gets that data and it just pushes in my

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phone however what happens here is you

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will notice that when I turn my phone

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that's a figuration change something

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happens and yeah so it just keeps on

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making that same EVP request over and

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over again every single time okay and

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the problem with making the HTTP

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requests over and over again every

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single time is like you are actually

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using real data in here like you are

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asking your whoever your your customers

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are whoever the people like your users

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are you are actually using real data in

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here and and that's a problem now let's

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go back so this is this is what the

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problem is now one change that we can

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make into this application is

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we can use something called life cycles

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and life cycles is a way for you to

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fetch some data so I have a load Pokemon

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methods in here I can fetch some data

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and that data gets saved into my

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applications memory but not into the

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unsaved instance so I'm using a life

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cycle class in here I have a add a

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function into my application that uses

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live data so whenever anything changes

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in my application life data just gets

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just get synonyms from here say hey and

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I just let you know there's been a

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change in data so we'll pay attention

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specifically to the live data here and

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the list that comes inside our life data

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now I obviously appreciate some people

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may not have used live data before so

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let me just explain what live data is

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very quickly for you so you have your UI

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in here so this is this is the

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application example I just used and then

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you have your live data object that

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holds the data for you so all the data

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that you want to show on the screen is

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inside the live data object so you can

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think about it like if you wanted to

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make a an analogy here you can say

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everything that is on live dates is like

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life dates is almost like my database

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okay so you have some data that gets

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stored in there and the UI is always

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observing live data so the UI is

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basically saying hey live data if

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there's a change I want to know about it

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I want to get an update so in this case

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I have an API which is the Polti API

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that I'm using and whenever there's a

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change from the API life there's old

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French those changes live data gets

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updated and live dates that would then

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tell my application that there's been a

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change my application would then react

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to that change and do whatever needs to

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be done so in this case you know some

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some road Pikachu just got into the

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polky API and just stick over the whole

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thing and everyone is a Pikachu now

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regardless of like which Pokemon they up

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and and that's how life data works so

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but now when you look at this

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application here you

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probably thinking oh okay so what if I

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what if I wanted to be able to click on

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on that Pikachu and see some details for

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example like how can I do that so that's

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where navigation components come about

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so navigation components are a way for

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you to basically do what the name says

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you can do navigation using navigation

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component so you can click on one of the

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items and you can navigate between

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Springs now the beauty of navigation is

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it basically handles all the data going

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forwards and the dates are coming back

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to you

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so with navigation you don't need to

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keep control that data because the

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navigation components do that for you

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the way navigation components this is a

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this is what a regular navigation would

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look like so in a simple application I

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you know I very much like the idea of

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like using a standardized way like

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that's that's one way and it can those

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navigation components handle the entire

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back stack for you so when I user

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navigates back in for for example the

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application just keeps track of

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everything our pokemon application is a

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perfect example of something like this

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because you could very easily just use

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the navigation components along with

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fragments to build something like a a

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single activity application so instead

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of having all the activities as you have

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in here if they have one activity a

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single activity application and you

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would use just like fragments to switch

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things around now navigation is a huge

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topic like there's a lot with navigation

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and one video will suggest watching like

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if you haven't done anything to do with

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navigation or specifically single

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activity applications there's a good

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supply and lake and this so this is when

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I had the pleasure to see back in 2018

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Android that summit it's on YouTube and

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there's a link on my slides I will be

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publishing those lives later as well so

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you don't need to be copying these links

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from here now navigation also has

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something that is a

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in my opinion is like the is the biggest

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selling point for me because what you

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can do with navigation and I'll just

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I'll just kind of give an example yeah I

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very often go into Stack Overflow and I

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look at like what are the Android

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developers asking the most like what are

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the questions Android developers are

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asking the most and I like doing that is

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because it helps me with like grey in my

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own sense like if I want to go and write

15:45

some people are blog for example you

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know it's it's cool to write about

15:49

something new but it's also cool to go

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and try and solve like answers some

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people's questions so I did that very

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often and one that kind of like got my

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attention here is looking at Stack

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Overflow if you look at the tab I'm

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looking at the frequent tab

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the question is how do I pass days

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between activities in an androids

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application and I went around and I

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clicked on this and I noticed like it's

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got a lot of uploads it's got a lot of

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like answers as well there doesn't seem

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to be an answer that is like the right

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and so like I don't think there was one

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when I looked but the most interesting

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thing here is there are a lot of pages

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and there are a lot of ways to actually

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skin a cat in here like you can you can

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do navigation in so many different ways

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and like people do them in so many

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different ways and I think this is the

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point of like using navigation

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components okay because and and again

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this whole like scrolling was just one

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page this is three pages of this okay so

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I can even I can even run this thing

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back for you in case you want to see

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that again it's quite it's quite pretty

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to look at but the point of like using

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navigation components is it's one way of

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doing things and it's one way that your

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entire team will know how to do and

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that's something I really enjoy because

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in a lot of this case and I looked and I

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looked at a lot of these answers here in

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a lot of these cases there's no right or

17:21

wrong like some people just implement

17:23

things in different way but there's not

17:25

really oh yeah this is the perfect way

17:27

of doing that's definitely the way I've

17:28

done it but there's no right or wrong in

17:31

the way navigation specifically passing

17:34

arguments between between navigation so

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this is a this is opposed by Lila

17:39

Fujiwara who works for Google and the

17:43

way Lila described navigation safe args

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like passing safe arguments in

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navigation is navigation components

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generates classes based off your

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navigation graph to ensure type safe

17:53

access to arguments for destinations in

17:56

actions so this is really cool because

17:59

everything that you pass between one

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activity to the other using navigation

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components if you use safe forms you're

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basically saying yeah this is all type

18:09

safe which is great and implementing

18:12

this is very very easy

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so in these things I have my I have my

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navigation graph in here and I create an

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argument which is the arguments I want

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and I can even have a default value so

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in this days in plastic now and I'm

18:24

saying this is an argumentative strain

18:26

so on the other sides if something tries

18:28

and reads Pennines

18:29

for example that's obviously not going

18:30

to work so it's making its making its

18:33

type safe which is which is super cool

18:37

then all my on my activity so this is

18:40

the button like if I had an on click so

18:43

when you rebuild your project you will

18:45

now have a directions class which I can

18:48

get next on an instance off and then in

18:51

this case what I'm doing is I'm updates

18:52

in the name of my Bulbasaur and I think

18:55

all navigates passing information so

18:57

again just using a single activity

18:59

application I can just go in a date the

19:01

name of my bubble sort and then

19:05

obviously on the other sides I just get

19:06

that like when my field gets created I

19:09

just get the name now if you're in your

19:12

receiving so that's your receiving

19:14

destination now here's how that would

19:19

look like so I have Bulbasaur in here

19:22

and when I click when I click on

19:24

Bulbasaur it turns that into cute

19:26

Bulbasaur so this is just like passing a

19:28

string okay it's not changing anything

19:31

in a database it's not doing anything

19:33

special

19:33

it's just fasting on a string now when

19:38

we're when we're passing a string with

19:39

safeguards its grace like if you want to

19:41

save stuff to a database but we haven't

19:43

done that yet so what if we wanted to

19:46

persist is like what if I wanted to

19:47

really rename my Bulbasaur so everywhere

19:51

when I look on my screen I see cute

19:54

Bulbasaur for example like what could I

19:55

do

19:56

if I wanted to do that so this is where

19:59

this is where room comes in so there's a

20:02

library for that tip and the way remarks

20:05

is room is a persistence library that

20:07

provides an abstraction layer for sicko

20:09

lights so if you've ever done anything

20:11

with sicko light you will know what a

20:15

pain it is like you will know what a

20:16

pain it is to actually maintain an

20:18

application that uses sick light just

20:20

natively I have used things in the past

20:23

like realm for example Rome was actually

20:27

pretty cool but I do think

20:28

Rome is is kind of in my opinion is is

20:31

the thing I've been using the most

20:32

because he could kind of

20:34

gets the best of realm and it gets the

20:35

best of like Jesse's in psycho lights

20:37

and in my opinion that's kind of like

20:41

the way I always go with now if I again

20:45

there are many many ways of doing

20:47

database interactions of sure that if I

20:49

go into Stack Overflow there's like a

20:51

few different ways of using psycho light

20:54

but the way you start using is we

20:56

already have a Pokemon data class as I

20:59

show during the code previously and it

21:02

looked it looks something like this I

21:04

have my name for Pokemon and I have a

21:06

URL what I then do is I create an entity

21:11

so I wrap this on an entity and I give

21:14

it a name so I can I think all my table

21:16

whatever so I'm calling my table Pokemon

21:18

so I haven't really made any changes to

21:21

my data class and I'm setting a primary

21:24

key like I'm giving it a primary key and

21:25

I'm saying my primary key it also

21:27

generates so whenever I add your Pokemon

21:29

it just gets a new it just gets in your

21:31

primary key so not doing anything

21:34

special in here but we can also remain

21:37

columns in here like if we wanted to if

21:39

when it mean to be something else or one

21:41

of names you like Pokemon name for

21:43

example we could also do that remember

21:45

I'm getting all this data from an API so

21:47

I obviously don't get things like ninety

21:49

but if the API had some like cryptic

21:51

names for example I could just change

21:53

that to be called something that is more

21:55

useful to me then I create a data access

21:60

object so this is just an interface and

22:02

here is where I can go in just the

22:05

Claire all of the the things on one of

22:07

the all the actions I want to do so I

22:08

have an excerpt I have an update I have

22:10

a query where it just go and select by

22:12

name for example and and the really

22:15

really cool thing about this like the

22:16

really cool thing about using this with

22:18

Android studio is they are all checked

22:21

at compile time and and I find this

22:25

really interesting so what I mean by

22:27

text by compile time is if I if I have a

22:30

typo on my codes for example I'm gonna

22:32

get in there that looks like this so

22:33

cannot resolve symbol Pokemon so it's

22:36

all it's all checked in compile time

22:38

which I find super interesting and then

22:42

if I fix this then the error kind of

22:44

disappears so this is like what under

22:46

Cydia does for you out

22:47

the box like you don't need to do

22:49

anything is obviously using the room

22:52

library this is 100 study of those out

22:55

of box then the next thing I need to do

22:57

is I need to actually set up my my

22:60

database so I need to implement my

23:02

database so I'm saying where my entities

23:04

are obviously I can have multiple

23:05

entities I am giving this a version so

23:08

if I want to go and bump the version I

23:10

can just bump that number and I said no

23:12

claims database and I say I'm using

23:15

Pokemon 0

23:17

I could have most fold 0 so like

23:19

multiple they type subjects in here and

23:22

then the last thing I need to do is I

23:24

just have a repository I'm using

23:26

recovery in this case and I'm saying

23:28

here's what my database name is Pokemon

23:30

Z B remember we names the table in the

23:33

past now you name the database

23:36

and I am just initializing my Pokemon

23:40

database and I'm saying database builder

23:42

so just like really initializing yet and

23:45

then I can start doing my chorus let

23:52

yeah okay so and this is this is my

23:55

database initializing initialization but

23:58

I wanted to I wanted to show you like

23:60

what this looks like in code as well so

24:03

I'm gonna come out of my presentation

24:05

here and I'm gonna show you some of my

24:07

code I'm gonna switch to rain

24:14

and this is like the amounts of changes

24:18

I've made on this application okay so

24:19

obviously I've created my zero here

24:22

my dates access object I have a methods

24:25

for each one of the things so I have a

24:26

methods for insert I have a method for

24:30

update I have a delete and I have a

24:32

select by name

24:34

I have a repulsor here my repository is

24:36

basically the thing that you've seen on

24:38

on the on the slides I'm making sure

24:42

things are async and everything and then

24:44

I have my database in so this is not

24:48

much different from what it was I can

24:51

now go and run this application and when

24:56

it finishes compiling hopefully I'll be

24:59

able to show you a little bit of like

25:01

how this is working right now

25:07

let me try and bring this here so I have

25:12

my Bulbasaur and what I can there is I

25:16

can from the application I can do things

25:19

like I'm gonna make this like pet and

25:22

then the Bulbasaur becomes my pet so now

25:25

I can go back I can go look at Ibis or

25:27

for examples or is the obviously not my

25:29

pet but if I go back to Bulbasaur I can

25:32

see Bulbasaur it's my pet and the way

25:35

I'm doing is the way I'm doing this I'm

25:37

just adding Bulbasaur into my database

25:40

and I'm saying I'm setting a boolean

25:43

flag to say Bulbasaur is my pet just

25:47

very simple as that so I'm not doing

25:49

anything special here but it's kind of

25:51

cool that I can that I can get database

25:54

like going on on my application without

25:57

actually having to write too much gold

25:60

in fact like I usually do this I usually

26:04

do this Bretton

26:05

usually when I did this presentation I

26:07

actually life codes this farce because

26:09

it's it's so simple but like an interest

26:11

of time in like giving people some

26:14

giving people some time for questions I

26:16

just don't wanna I just don't want to

26:18

take up all the time now I'll go back

26:21

into my slides here so we looked at that

26:23

demo

26:26

now if you wanna if you want to know

26:29

more there are gonna be a couple more

26:32

things going on today so we obviously

26:36

have camera X camera X's I'll say it's

26:40

probably my favorite API in jetpack I I

26:46

had a lot of fun building things the

26:48

camera X I wrote a blog post about it so

26:50

you can check it out to my blog and

26:52

there's also become a composer so I

26:54

purposely didn't mention those things in

26:56

my application even though camera X is

26:58

probably my favorite librarian jetpack I

26:60

didn't mention those things as I knew

27:02

Brian ends idea we're gonna talk about

27:05

those see things so Brian he's talking

27:07

about become a composer Divya is talking

27:09

about camera X composer is super super

27:12

interesting it's still a bit fiddly as

27:15

you will see today but it's super super

27:17

interesting and I think I'm Brian would

27:18

do a good job explaining that with that

27:22

like I said I will be posting those

27:24

lights later I'll put it on whatever

27:26

hashtag Greg tells me to cut on Twitter

27:30

you can find me on Twitter on Marcus

27:32

patron on Twitter all this code is also

27:35

github it's gonna be on my github

27:37

account and you can check a lot of my

27:40

sorts of like answers to Stack Overflow

27:42

questions like unified answers or even

27:46

like a lot of the the open source that I

27:48

write you can find out become a doctor

27:50

dr. K which is my website with that I

27:53

want to thank you and I want to thank

27:55

drug con very much for having me I have

27:58

been Marcus back on it's a pleasure to

27:59

be here Thank You Marcos thanks so much

28:02

fantastic presentation really appreciate

28:04

you being here

28:05

we have Q&A I'm gonna have Willie

28:08

changed himself to the presenter so

28:10

everyone can see the top questions that

28:12

were voted on will give you ten minutes

28:14

to answer them and I'll bring everyone

28:17

back in and introduce Divya after that

28:21

cool

28:24

so feel free to fire away Marcus anytime

28:28

cool all right so I am looking at the

28:32

first question with mostly modular

28:34

architecture work in each module at

28:38

least one activity on the rise isn't a

28:41

single I'm not sure I really understand

28:48

yeah with multi modular architecture

28:51

where each module equals okay so where

28:54

each module equals at least one activity

28:57

on the right is the single activity on

29:02

updated I'm not sure I understand this

29:06

question if there's anyone else who

29:09

wants to help me answer the question

29:10

because I'm not sure I even understand

29:12

it I'm gonna move on to the next

29:15

question and come back to this so the

29:17

next question is is there any

29:19

performance difference between is there

29:21

any performance differences between

29:22

implementing a map with multiple

29:24

activities and implementing an app with

29:26

one activity and multiple fragments I

29:28

haven't seen anything like this

29:31

using multiple fragments in my in my my

29:36

opinion as developer using multiple

29:38

fragments this complicates your code a

29:42

little bit but I haven't seen any kind

29:46

of like performance differences what I

29:48

would say is if your application is very

29:50

complex you probably don't want to make

29:52

it a single activity application and

29:54

just keep on like spawning new fragments

29:57

but if you're if you have like an

29:59

application like the Pokemon application

30:02

for example that I just showed you that

30:03

is the perfect contender for like just

30:06

using nodes for fragments because you

30:07

don't have many of them I'll say if you

30:09

have many fragments then you just need

30:12

to be careful that to the next question

30:17

in and the questions keep on like

30:19

popping around which is really exciting

30:21

in a mostly modular project what's the

30:24

best design using navigation jetpack to

30:29

go from fragments in module a to

30:31

fragment in module B

30:36

in a multi module projects was the best

30:39

design using navigation don't Peck I'm

30:47

not sure I get this I know this is I

30:49

know we're talking about a multi module

30:51

but I'm not sure I get the question

30:55

I don't I don't think you do anything

30:57

different in here like I work with some

31:01

applications that are mostly module and

31:03

I've been using fragments on those

31:04

applications so I don't think you'd do

31:07

anything different in here other than

31:08

just like injecting the the fragment I

31:13

don't think there's anything different

31:17

that you need to do unless I didn't

31:21

quite get the question I have answered

31:25

this one already now the next question

31:30

I'm gonna go to if I'm using the same

31:33

fragment in different Navigation graphs

31:36

I need to update questions as it appears

31:42

[Music]

31:45

what is the best way to map Nessa Jason

31:48

into a room database

31:50

okay I'm gonna answer that because I I'm

31:54

gonna answer that because it's the one I

31:56

got to read what is the way to map what

31:59

you do is I usually just try and map the

32:02

Jason into Data class I get a I get my

32:05

data class and I map it that way so

32:08

Jason entities into you have a lot of

32:12

like generators of usually like what I

32:15

did last time I had today this was

32:17

obvious that generator that basically

32:19

takes my Jason turns into like a POJO

32:23

and I just pasted that into you into

32:27

Andres video and there's three or

32:28

obviously just translated that

32:34

oh there's someone second script under

32:36

its 300 bees translated that to Kotlin

32:38

and then I just turned that into a day

32:39

to class and that's the easiest way you

32:41

can do it like it is

32:43

I'd say if there's like 90% of the job

32:45

for you so yeah that's that's how I do

32:50

it

32:51

do you think it's the best practice to

32:52

use activity per feet Jesus I'll move to

32:57

the browser okay because I'm looking at

32:58

the I'm looking at screen here big tips

33:00

on popping so I'll move to the browser

33:02

yeah

33:14

and I'm just opening here is there is a

33:24

you prefer using navigation say fogs

33:26

instead of parcel eyes data class in

33:29

Kotlin close the new interns fragment

33:33

new instance I'll say no so that's also

33:38

the I'm gonna read the question again is

33:40

there are reasons we prefer using

33:41

navigation safe args instead of partial

33:44

eyes data class teen Kotlin plus the new

33:47

intent fragments new instance parsing

33:50

I'll say no III think that's more of a

33:52

preference I if I'm using if I'm using

33:55

jetpack which is what I tend to use

33:57

right now whenever I use it I just use

33:59

safe args

33:60

now I don't think there's a right or

34:01

wrong in here unless I didn't get the

34:04

question rise but I don't think there's

34:05

a right or wrong using using sorts of

34:07

like Newton's we fragment new instance

34:10

parts and is almost like a you kind of

34:12

like go it's almost like you're going

34:13

under the hood on the on the navigation

34:16

safeguard so I all say this is probably

34:18

more of a preference thing than anything

34:20

else all right

34:23

Marcus we have time for we have time for

34:25

one more question so that's possibly two

34:29

but let's try to get to more questions

34:31

and then okay to the next one and I'm

34:36

looking at my browser now because

34:37

they're like just looking at the screen

34:39

here like the questions is just keep on

34:41

changing

34:43

what about they turbine zine is it

34:46

passive jetpack if used correctly and

34:48

with only two doesn't it result in

34:52

untestable code they surprisingly

34:54

doesn't it doesn't results in accessible

34:56

code no beta binding is you can use it

35:02

as farce of jetpack yes I use data

35:05

binding a lot I'm not sure it results in

35:09

untestable calls I think

35:11

I you know I think most of the

35:15

impossible cause I've seen is like

35:16

written by developers such as ceasing

35:19

functionality so I would say I don't

35:22

think it results in untestable goals

35:23

unless you you had like a different

35:26

experience like I never really had an

35:27

experience where I'm a fuse databinding

35:30

and I used a turbines Nia laughs and I

35:31

never had an experience where like I can

35:34

test all my code because a bit cold yes

35:44

there's one question here that says on

35:47

asynctasks

35:48

deprecated yes async task is deprecated

35:51

as I was talking about it today like

35:53

looking at my goals I was like yeah I

35:55

should have changed that yes async tasks

35:57

our deprecated so you should you should

35:59

move away from using async tasks there

36:04

are definitely new different things that

36:06

you can use I actually wrote an entire

36:08

blog post about this so if you want to

36:10

know what you can what you can using

36:14

stands I wrote a blog post about called

36:17

that UK where I talk about async tasks

36:20

in their deprecation so you are right

36:22

mr. anonymous async tasks are deprecated

36:26

Marcus thanks so much thanks also for

36:29

playing

36:30

question roulette with us you know so

36:35

this is a process we're gonna refine in

36:38

the next but hopefully we'll be cycling

36:40

through the always the top three vote

36:43

and on questions will appear on the

36:44

screen the latest question will keep

36:46

appearing down below and changing so

36:49

hopefully that'll smooth out but thanks

36:51

for playing roulette with us on the

36:53

questions and for the fantastic

36:55

presentation no where's my pleasure

36:58

thank you everyone for having here again

37:00

I'm happy to answer your if you have a

37:03

question I'm happy to answer those on

37:05

Twitter is also just like at me on

37:07

sweets and I'm happy to try and answer

37:09

your questions here thank you

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