AppRegistry

Project with Native Code Required

If you are using the managed Expo workflow there is only ever one entry component registered with AppRegistry and it is handled automatically (or through registerRootComponent). You do not need to use this API.

AppRegistry is the JS entry point to running all React Native apps. App root components should register themselves with AppRegistry.registerComponent, then the native system can load the bundle for the app and then actually run the app when it's ready by invoking AppRegistry.runApplication.

tsx

import {Text, AppRegistry} from 'react-native';

const App = () => (
  <View>
    <Text>App1</Text>
  </View>
);

AppRegistry.registerComponent('Appname', () => App);

To "stop" an application when a view should be destroyed, call AppRegistry.unmountApplicationComponentAtRootTag with the tag that was passed into runApplication. These should always be used as a pair.

AppRegistry should be required early in the require sequence to make sure the JS execution environment is setup before other modules are required.

---

Reference

Methods

getAppKeys()

tsx

static getAppKeys(): string[];

Returns an array of strings.

---

getRegistry()

tsx

static getRegistry(): {sections: string[]; runnables: Runnable[]};

Returns a Registry object.

---

getRunnable()

tsx

static getRunnable(appKey: string): : Runnable | undefined;

Returns a Runnable object.

Parameters:

Name	Type
appKey Required	string

---

getSectionKeys()

tsx

static getSectionKeys(): string[];

Returns an array of strings.

---

getSections()

tsx

static getSections(): Record<string, Runnable>;

Returns a Runnables object.

---

registerCancellableHeadlessTask()

tsx

static registerCancellableHeadlessTask(
  taskKey: string,
  taskProvider: TaskProvider,
  taskCancelProvider: TaskCancelProvider,
);

Register a headless task which can be cancelled. A headless task is a bit of code that runs without a UI.

Parameters:

Name	Type	Description
taskKey Required	string	The native id for this task instance that was used when startHeadlessTask was called.
taskProvider Required	TaskProvider	A promise returning function that takes some data passed from the native side as the only argument. When the promise is resolved or rejected the native side is notified of this event and it may decide to destroy the JS context.
taskCancelProvider Required	TaskCancelProvider	a void returning function that takes no arguments; when a cancellation is requested, the function being executed by taskProvider should wrap up and return ASAP.

---

registerComponent()

tsx

static registerComponent(
  appKey: string,
  getComponentFunc: ComponentProvider,
  section?: boolean,
): string;

Parameters:

Name	Type
appKey Required	string
componentProvider Required	ComponentProvider
section	boolean

---

registerConfig()

tsx

static registerConfig(config: AppConfig[]);

Parameters:

Name	Type
config Required	AppConfig[]

---

registerHeadlessTask()

tsx

static registerHeadlessTask(
  taskKey: string,
  taskProvider: TaskProvider,
);

Register a headless task. A headless task is a bit of code that runs without a UI.

This is a way to run tasks in JavaScript while your app is in the background. It can be used, for example, to sync fresh data, handle push notifications, or play music.

Parameters:

Name	Type	Description
taskKey Required	string	The native id for this task instance that was used when startHeadlessTask was called.
taskProvider Required	TaskProvider	A promise returning function that takes some data passed from the native side as the only argument. When the promise is resolved or rejected the native side is notified of this event and it may decide to destroy the JS context.

---

registerRunnable()

tsx

static registerRunnable(appKey: string, func: Runnable): string;

Parameters:

Name	Type
appKey Required	string
run Required	function

---

registerSection()

tsx

static registerSection(
  appKey: string,
  component: ComponentProvider,
);

Parameters:

Name	Type
appKey Required	string
component Required	ComponentProvider

---

runApplication()

tsx

static runApplication(appKey: string, appParameters: any): void;

Loads the JavaScript bundle and runs the app.

Parameters:

Name	Type
appKey Required	string
appParameters Required	any

---

setComponentProviderInstrumentationHook()

tsx

static setComponentProviderInstrumentationHook(
  hook: ComponentProviderInstrumentationHook,
);

Parameters:

Name	Type
hook Required	function

A valid hook function accepts the following as arguments:

Name	Type
component Required	ComponentProvider
scopedPerformanceLogger Required	IPerformanceLogger

The function must also return a React Component.

---

setWrapperComponentProvider()

tsx

static setWrapperComponentProvider(
  provider: WrapperComponentProvider,
);

Parameters:

Name	Type
provider Required	ComponentProvider

---

startHeadlessTask()

tsx

static startHeadlessTask(
  taskId: number,
  taskKey: string,
  data: any,
);

Only called from native code. Starts a headless task.

Parameters:

Name	Type	Description
taskId Required	number	The native id for this task instance to keep track of its execution.
taskKey Required	string	The key for the task to start.
data Required	any	The data to pass to the task.

---

unmountApplicationComponentAtRootTag()

tsx

static unmountApplicationComponentAtRootTag(rootTag: number);

Stops an application when a view should be destroyed.

Parameters:

Name	Type
rootTag Required	number

Type Definitions

AppConfig

Application configuration for the registerConfig method.

Type
object

Properties:

Name	Type
appKey Required	string
component	ComponentProvider
run	function
section	boolean

note

Every config is expected to set either component or run function.

Registry

Type
object

Properties:

Name	Type
runnables	array of Runnables
sections	array of strings

Runnable

Type
object

Properties:

Name	Type
component	ComponentProvider
run	function

Runnables

An object with key of appKey and value of type of Runnable.

Type
object

Task

A Task is a function that accepts any data as argument and returns a Promise that resolves to undefined.

Type
function

TaskCanceller

A TaskCanceller is a function that accepts no argument and returns void.

Type
function

TaskCancelProvider

A valid TaskCancelProvider is a function that returns a TaskCanceller.

Type
function

TaskProvider

A valid TaskProvider is a function that returns a Task.

Type
function