You can not select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
145 lines
7.2 KiB
145 lines
7.2 KiB
![Now in Android](docs/images/nia-splash.jpg "Now in Android")
|
|
|
|
<a href="https://play.google.com/store/apps/details?id=com.google.samples.apps.nowinandroid"><img src="https://play.google.com/intl/en_us/badges/static/images/badges/en_badge_web_generic.png" height="70"></a>
|
|
|
|
Now in Android App
|
|
==================
|
|
|
|
**Learn how this app was designed and built in the [design case study](https://goo.gle/nia-figma), [architecture learning journey](docs/ArchitectureLearningJourney.md) and [modularization learning journey](docs/ModularizationLearningJourney.md).**
|
|
|
|
This is the repository for the [Now in Android](https://developer.android.com/series/now-in-android)
|
|
app. It is a **work in progress** 🚧.
|
|
|
|
**Now in Android** is a fully functional Android app built entirely with Kotlin and Jetpack Compose. It
|
|
follows Android design and development best practices and is intended to be a useful reference
|
|
for developers. As a running app, it's intended to help developers keep up-to-date with the world
|
|
of Android development by providing regular news updates.
|
|
|
|
The app is currently in development. The `demoRelease` variant is [available on the Play Store in open beta](https://play.google.com/store/apps/details?id=com.google.samples.apps.nowinandroid).
|
|
|
|
# Features
|
|
|
|
**Now in Android** displays content from the
|
|
[Now in Android](https://developer.android.com/series/now-in-android) series. Users can browse for
|
|
links to recent videos, articles and other content. Users can also follow topics they are interested
|
|
in or follow specific authors.
|
|
|
|
## Screenshots
|
|
|
|
![Screenshot showing For You screen, Interests screen and Topic detail screen](docs/images/screenshots.png "Screenshot showing For You screen, Interests screen and Topic detail screen")
|
|
|
|
# Development Environment
|
|
|
|
**Now in Android** uses the Gradle build system and can be imported directly into the latest stable
|
|
version of Android Studio (available [here](https://developer.android.com/studio)). The `debug`
|
|
build can be built and run using the default configuration.
|
|
|
|
Once you're up and running, you can refer to the learning journeys below to get a better
|
|
understanding of which libraries and tools are being used, the reasoning behind the approaches to
|
|
UI, testing, architecture and more, and how all of these different pieces of the project fit
|
|
together to create a complete app.
|
|
|
|
NOTE: Building the app using an M1 Mac will require the use of
|
|
[Rosetta](https://support.apple.com/en-gb/HT211861). See
|
|
[the following bug](https://github.com/protocolbuffers/protobuf/issues/9397#issuecomment-1086138036)
|
|
for more details.
|
|
|
|
# Architecture
|
|
|
|
The **Now in Android** app follows the
|
|
[official architecture guidance](https://developer.android.com/topic/architecture)
|
|
and is described in detail in the
|
|
[architecture learning journey](docs/ArchitectureLearningJourney.md).
|
|
|
|
# Modularization
|
|
|
|
The **Now in Android** app has been fully modularized and you can find the detailed guidance and
|
|
description of the modularization strategy used in
|
|
[modularization learning journey](docs/ModularizationLearningJourney.md).
|
|
|
|
# Build
|
|
|
|
The app contains the usual `debug` and `release` build variants.
|
|
|
|
In addition, the `benchmark` variant of `app` is used to test startup performance and generate a
|
|
baseline profile (see below for more information).
|
|
|
|
`app-nia-catalog` is a standalone app that displays the list of components that are stylized for
|
|
**Now in Android**.
|
|
|
|
The app also uses
|
|
[product flavors](https://developer.android.com/studio/build/build-variants#product-flavors) to
|
|
control where content for the app should be loaded from.
|
|
|
|
The `demo` flavor uses static local data to allow immediate building and exploring of the UI.
|
|
|
|
The `prod` flavor makes real network calls to a backend server, providing up-to-date content. At
|
|
this time, there is not a public backend available.
|
|
|
|
For normal development use the `demoDebug` variant. For UI performance testing use the
|
|
`demoRelease` variant.
|
|
|
|
# Testing
|
|
|
|
To facilitate testing of components, **Now in Android** uses dependency injection with
|
|
[Hilt](https://developer.android.com/training/dependency-injection/hilt-android).
|
|
|
|
Most data layer components are defined as interfaces.
|
|
Then, concrete implementations (with various dependencies) are bound to provide those interfaces to
|
|
other components in the app.
|
|
In tests, **Now in Android** notably does _not_ use any mocking libraries.
|
|
Instead, the production implementations can be replaced with test doubles using Hilt's testing APIs
|
|
(or via manual constructor injection for `ViewModel` tests).
|
|
|
|
These test doubles implement the same interface as the production implementations and generally
|
|
provide a simplified (but still realistic) implementation with additional testing hooks.
|
|
This results in less brittle tests that may exercise more production code, instead of just verifying
|
|
specific calls against mocks.
|
|
|
|
Examples:
|
|
- In instrumentation tests, a temporary folder is used to store the user's preferences, which is
|
|
wiped after each test.
|
|
This allows using the real `DataStore` and exercising all related code, instead of mocking the
|
|
flow of data updates.
|
|
|
|
- There are `Test` implementations of each repository, which implement the normal, full repository
|
|
interface and also provide test-only hooks.
|
|
`ViewModel` tests use these `Test` repositories, and thus can use the test-only hooks to
|
|
manipulate the state of the `Test` repository and verify the resulting behavior, instead of
|
|
checking that specific repository methods were called.
|
|
|
|
# UI
|
|
The app was designed using [Material 3 guidelines](https://m3.material.io/). Learn more about the design process and
|
|
obtain the design files in the [Now in Android Material 3 Case Study](https://goo.gle/nia-figma) (design assets [also available as a PDF](docs/Now-In-Android-Design-File.pdf)).
|
|
|
|
The Screens and UI elements are built entirely using [Jetpack Compose](https://developer.android.com/jetpack/compose).
|
|
|
|
The app has two themes:
|
|
|
|
- Dynamic color - uses colors based on the [user's current color theme](https://material.io/blog/announcing-material-you) (if supported)
|
|
- Default theme - uses predefined colors when dynamic color is not supported
|
|
|
|
Each theme also supports dark mode.
|
|
|
|
The app uses adaptive layouts to
|
|
[support different screen sizes](https://developer.android.com/guide/topics/large-screens/support-different-screen-sizes).
|
|
|
|
Find out more about the [UI architecture here](docs/ArchitectureLearningJourney.md#ui-layer).
|
|
|
|
# Baseline profiles
|
|
|
|
The baseline profile for this app is located at [`app/src/main/baseline-prof.txt`](app/src/main/baseline-prof.txt).
|
|
It contains rules that enable AOT compilation of the critical user path taken during app launch.
|
|
For more information on baseline profiles, read [this document](https://developer.android.com/studio/profile/baselineprofiles).
|
|
|
|
> Note: The baseline profile needs to be re-generated for release builds that touch code which changes app startup.
|
|
|
|
To generate the baseline profile, select the `benchmark` build variant and run the
|
|
`BaselineProfileGenerator` benchmark test on an AOSP Android Emulator.
|
|
Then copy the resulting baseline profile from the emulator to [`app/src/main/baseline-prof.txt`](app/src/main/baseline-prof.txt).
|
|
|
|
# License
|
|
|
|
**Now in Android** is distributed under the terms of the Apache License (Version 2.0). See the
|
|
[license](LICENSE) for more information.
|