SPEAKER 1: Hey, everybody.

Welcome back to What's New in Android.

SPEAKER 2: First, we'll start with distribution. you.

You saw in the keynote, we introduced the dynamic app

bundles.

Towards the end, it was pretty clear it's pretty easy for you.

All you have to do is click a different menu

when you build your application.

And we're going to save you some space.

It's going to be faster and easier for your users

to download your app.

SPEAKER 1: Let's talk about Android Jetpack.

This is a set of components as well as

guidance on how to build better Android applications.

All of you are familiar with most of what

is in Android Jetpack already.

What we're doing is adding to it over time

with stuff that's going to make it even better.

And we're also improving it over time.

One of the major steps that we're taking

is what I like to think of as a refactor, because it's

a refactor.

And we're doing a whole lot of tedious renaming.

And we're also providing tools to make it easier

for you to do the similar refactoring that you're

going to need to do in your application,

as well as in Android Studio.

Everything is being renamed to something more appropriate

called Androidx.

Jetpack architecture is about architecture components

that were announced last year at I/O,

and then iterated with feedback from the community,

and finally went 1.0 in the fall.

Work Manager is currently in preview.

There's going to be a talk about it.

Also navigation-- it turns out that up versus

back is a hard problem for applications to solve.

We are making that much easier, and we're

integrating with the tool to make it even easier yet.

SPEAKER 2: Kotlin-- it's the [INAUDIBLE]

thing we announced last year.

So we're busy.

We want to make it better for all the Kotlin developers

out there.

I'm sure there's a lot of you here today.

So some of the things we've been doing.

The ART team has been really busy with D8, R8, and ART

itself.

They've been looking at the bytecode generated

by the Kotlin compiler.

They've analyzed some of the bytecode patterns that

were different from the ones generated by the Java

programming language compiler.

And they've been optimizing for those patterns.

We've also been adding a lot of nullability annotations

to our Java APIs, both in the core libraries--

so libcore-- and our support libraries

to make it easier for you to use the platform

APIs when you're in Kotlin.

And finally, we launched on GitHub

a new library called android-ktx.

It's a set of Kotlin extensions for existing platform APIs.

And the goal here is to try to take advantage

of some of the Kotlin language features

to make existing APIs easier to use.

They're already easier to use just by using Kotlin,

but with the extension, they get even better.

SPEAKER 3: So Slices is our new approach to remote content

that you can actually use to project UI into your own app

or into other apps that support it.

It's very structured.

This is not sort of here's a canvas or an absolute layout.

Go nuts with it.

We give you a structure to fill out and a whole bunch of very

flexible templates in which to populate that data with some

display hints, so that the receiving end of the Slice--

the Slice host--

kind of knows what to do with it.

These are interactive.

These are updateable.

This is meant to be something that holds rich UI-- sliders,

controls, live information, possibly videos--

things that actually feel like real UI as opposed

to a snapshot of something happening in a distant process

somewhere.

Slices are addressable by content URI,

and this is how they're passed around the system

and how they're passed along to app indexing

to be shown in context-like search.

And then finally, Slices is entirely

inside the support library.

It's entirely in Jetpack, so it's backwards-compatible.

You can use Slices all the way back to API 19.

Related to Slices is Actions.

You can think of these as shortcuts with parameters.

[INAUDIBLE] likes to think of them as visible intents.

This is essentially a deep link into your app

with some additional payload.

It's not just a link to music.

It's linked to the particular album or something like that.

And you saw these as well in the keynotes,

showing up in predictive space inside our app launching

experience--

actions you define in an actions XML

file that goes into your APK or app bundle.

And that too can get registered with app indexing

so that search results and predictive features

can show those actions.

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