Jetpack Compose is a suite of libraries within the AndroidX ecosystem. For more information, see our project page
Jetpack Compose uses composable functions instead of XML layouts to define UI components. You can see this in action in the demos, like
androidx.compose.material.demos.ButtonDemo.kt. More information can be found in the compiler README.
You may notice some parts of the codebase use an XML-like syntax. This was an exploration done early on in the project, and we have since decided to move away from it. Usages of this syntax will eventually be converted to use the standard kotlin DSL instead.
Composable functions are built using a custom Kotlin compiler plugin. More information about the compiler plugin is available in this README.
To try out Jetpack Compose you need to set up the toolchain for AndroidX development. Follow the process here to check out the code.
To start the required version of Android Studio, you need to run the studiow command from the
cd path/to/checkout/frameworks/support/ui/ ./studiow
Also if you would like to build from the command line, all gradle commands need to be run from the
/ui subfolder. E.g. to build the demo app, run:
cd path/to/checkout/frameworks/support/ui/ ./gradlew ui:integration-tests:demos:installDebug
Jetpack Compose is in very early stages of development. Developers wanting to build sample apps will probably want to include the material, layout and framework modules. You can see how to setup your dependencies in
demos app to see examples of individual components.
A sample implementation of the Material Rally app is under
material/integration-tests/material-studies. This can be viewed from inside the
demos app, under the ‘Material Studies’ section.
Library code for Jetpack Compose lives under the
frameworks/support/ui directory. Additionally, sample code can be found within each module in the
integration-tests subdirectories and the compiler and runtime code can be found in
The modules within UI are structured as follows:
Wrappers and adapters for existing Android Views
Internal declarations for the animations system
Classes and components used across the system for layout, drawing, root views, etc.
Module that collects all demos across ui and packages them into one demo APK
Basic layout components
Set of UI components built according to the Material spec
Base Text composables
Text engine that contains base text components
Android specific text stack dependent implementations