Documentation Index
Fetch the complete documentation index at: https://mintlify.com/facebook/react-native/llms.txt
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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 run it when ready by invoking AppRegistry.runApplication.
Methods
registerComponent()
static registerComponent(
appKey: string,
componentProvider: () => React.ComponentType<any>,
section?: boolean
): string
appKey: String name for the applicationcomponentProvider: Function that returns a React componentsection: Optional boolean to register as a section
Returns:
- The
appKey that was registered
Example:
import { AppRegistry } from 'react-native';
import App from './App';
AppRegistry.registerComponent('MyApp', () => App);
runApplication()
static runApplication(
appKey: string,
appParameters: any,
displayMode?: number
): void
appKey: The string name of the app to runappParameters: Object containing:
initialProps: Props to pass to the root componentrootTag: The native root view tagfabric: Whether Fabric renderer is enabled
displayMode: Optional display mode configuration
Example:
import { AppRegistry } from 'react-native';
AppRegistry.runApplication('MyApp', {
initialProps: { userId: '123' },
rootTag: 1,
});
unmountApplicationComponentAtRootTag()
static unmountApplicationComponentAtRootTag(rootTag: number): void
runApplication.
Parameters:
rootTag: The root tag that was passed to runApplication
Example:
import { AppRegistry } from 'react-native';
AppRegistry.unmountApplicationComponentAtRootTag(1);
registerHeadlessTask()
static registerHeadlessTask(
taskKey: string,
taskProvider: () => (taskData: any) => Promise<void>
): void
taskKey: Unique string identifier for the tasktaskProvider: Function that returns an async task function
Example:
import { AppRegistry } from 'react-native';
const MyTask = async (taskData) => {
console.log('Headless task running with data:', taskData);
// Perform background work
};
AppRegistry.registerHeadlessTask('MyTask', () => MyTask);
registerCancellableHeadlessTask()
static registerCancellableHeadlessTask(
taskKey: string,
taskProvider: () => (taskData: any) => Promise<void>,
taskCancelProvider: () => () => void
): void
taskKey: Unique string identifier for the tasktaskProvider: Function that returns an async task functiontaskCancelProvider: Function that returns a cancellation function
Example:
import { AppRegistry } from 'react-native';
let taskCancelled = false;
const MyTask = async (taskData) => {
for (let i = 0; i < 100; i++) {
if (taskCancelled) break;
// Do work
}
};
AppRegistry.registerCancellableHeadlessTask(
'MyCancellableTask',
() => MyTask,
() => () => { taskCancelled = true; }
);
startHeadlessTask()
static startHeadlessTask(
taskId: number,
taskKey: string,
data: any
): void
taskId: Numeric ID for this task instancetaskKey: The registered task keydata: Data to pass to the task
cancelHeadlessTask()
static cancelHeadlessTask(
taskId: number,
taskKey: string
): void
taskId: The task instance IDtaskKey: The registered task key
setSurfaceProps()
static setSurfaceProps(
appKey: string,
appParameters: any,
displayMode?: number
): void
appKey: The registered app keyappParameters: New parameters/propsdisplayMode: Optional display mode
getAppKeys()
static getAppKeys(): string[]
- Array of registered application keys
getRunnable()
static getRunnable(appKey: string): Runnable | undefined
appKey: The app key to look up
Returns:
- The runnable function or undefined if not found
Typical Usage
In your app’s entry file (usually index.js):
import { AppRegistry } from 'react-native';
import App from './App';
import { name as appName } from './app.json';
AppRegistry.registerComponent(appName, () => App);