LiveActivity

The LiveActivity API enables you to display real-time, dynamic information from your script on the Lock Screen and, where supported, in the Dynamic Island on iOS devices. It provides a structured interface to start, update, and end Live Activities, and observe their state throughout their lifecycle.

This document provides a complete guide to using the LiveActivity API in the Scripting app, including:

  • Core concepts and lifecycle
  • How to register a Live Activity UI
  • How to start, update, and end Live Activities
  • UI layout for Dynamic Island and Lock Screen
  • Full TypeScript/TSX examples
  • Detailed descriptions of every type and option

The API wraps Apple’s ActivityKit and brings it into the Scripting environment with a React-style UI building approach.


1. Understanding Live Activities

A Live Activity can appear in the following regions:

  • Lock Screen
  • Dynamic Island (iPhone 14 Pro and later)
  • Banner-style presentation on devices without Dynamic Island

Live Activities are used for time-based and progress-based information, such as:

  • Timers
  • Fitness progress
  • Delivery tracking
  • Countdowns and reminders
  • Real-time status updates

In Scripting, each Live Activity consists of:

  1. contentState (a JSON-serializable object that updates over time)
  2. UI Builder (a function that produces TSX UI for each state)

2. Live Activity State Types

type LiveActivityState = "active" | "dismissed" | "ended" | "stale";
StateDescription
activeThe Live Activity is visible and can receive content updates.
staleThe Live Activity is out of date. The system expects an update.
endedThe Live Activity ended but may remain visible for up to four hours or a user-defined time.
dismissedThe Live Activity is no longer visible.

3. LiveActivityDetail Type

type LiveActivityDetail = {
  id: string;
  state: LiveActivityState;
};

Represents a summary of each active Live Activity.


4. Live Activity UI Types

4.1 LiveActivityUIProps

type LiveActivityUIProps = {
  content: VirtualNode;
  compactLeading: VirtualNode;
  compactTrailing: VirtualNode;
  minimal: VirtualNode;
  children: VirtualNode | VirtualNode[];
};

These regions correspond to ActivityKit’s UI areas:

PropertyRegion
contentLock Screen and non–Dynamic Island devices
compactLeadingLeading area of compact Dynamic Island
compactTrailingTrailing area of compact Dynamic Island
minimalThe smallest pill-style display
childrenThe expanded Dynamic Island layout (multiple regions)

5. Registering a Live Activity UI

Live Activities must be registered inside a standalone file such as live_activity.tsx.

import { LiveActivity, LiveActivityUI, LiveActivityUIBuilder } from "scripting";

export type State = {
  mins: number;
};

function ContentView(state: State) {
  return (
    <HStack activityBackgroundTint={{ light: "clear", dark: "clear" }}>
      <Image systemName="waterbottle" foregroundStyle="systemBlue" />
      <Text>{state.mins} minutes left until the next drink</Text>
    </HStack>
  );
}

const builder: LiveActivityUIBuilder<State> = (state) => {
  return (
    <LiveActivityUI
      content={<ContentView {...state} />}
      compactLeading={
        <HStack>
          <Image systemName="clock" />
          <Text>{state.mins}m</Text>
        </HStack>
      }
      compactTrailing={<Image systemName="waterbottle" foregroundStyle="systemBlue" />}
      minimal={<Image systemName="clock" />}>
      <LiveActivityUIExpandedCenter>
        <ContentView {...state} />
      </LiveActivityUIExpandedCenter>
    </LiveActivityUI>
  );
};

export const MyLiveActivity = LiveActivity.register("MyLiveActivity", builder);

6. Using a Live Activity in Your Script

import {
  Button,
  Text,
  VStack,
  Navigation,
  NavigationStack,
  useMemo,
  useState,
  LiveActivityState,
  BackgroundKeeper,
} from "scripting";

import { MyLiveActivity } from "./live_activity";

function Example() {
  const dismiss = Navigation.useDismiss();
  const [state, setState] = useState<LiveActivityState>();

  const activity = useMemo(() => {
    const instance = MyLiveActivity();

    instance.addUpdateListener((s) => {
      setState(s);
      if (s === "dismissed") {
        BackgroundKeeper.stop();
      }
    });

    return instance;
  }, []);

  return (
    <NavigationStack>
      <VStack
        navigationTitle="Live Activity Example"
        navigationBarTitleDisplayMode="inline"
        toolbar={{
          cancellationAction: <Button title="Done" action={dismiss} />,
        }}>
        <Text>Activity State: {state ?? "-"}</Text>

        <Button
          title="Start Live Activity"
          disabled={state != null}
          action={() => {
            let count = 5;
            BackgroundKeeper.keepAlive();

            activity.start({ mins: count });

            function tick() {
              setTimeout(() => {
                count -= 1;
                if (count === 0) {
                  activity.end({ mins: 0 });
                  BackgroundKeeper.stop();
                } else {
                  activity.update({ mins: count });
                  tick();
                }
              }, 60000);
            }

            tick();
          }}
        />
      </VStack>
    </NavigationStack>
  );
}

async function run() {
  await Navigation.present(<Example />);
  Script.exit();
}

run();

7. LiveActivity Class API Reference

7.1 start(contentState, options?)

start(contentState: T, options?: LiveActivityOptions): Promise<boolean>

Starts a Live Activity.

LiveActivityOptions

type LiveActivityOptions = {
  staleDate?: number | Date;
  relevanceScore?: number;
};
  • staleDate: Timestamp(ms) or Date object at which the activity becomes stale
  • relevanceScore: Determines which Live Activity is prioritized in the Dynamic Island

7.2 update(contentState, options?)

update(contentState: T, options?: LiveActivityUpdateOptions)

LiveActivityUpdateOptions

type LiveActivityUpdateOptions = {
  staleDate?: number | Date;
  relevanceScore?: number;
  alert?: {
    title: string;
    body: string;
  };
};

Alerts appear on Apple Watch when sending an update.


7.3 end(contentState, options?)

end(contentState: T, options?: LiveActivityEndOptions)

LiveActivityEndOptions

type LiveActivityEndOptions = {
  staleDate?: numberDate
  relevanceScore?: number
  dismissTimeInterval?: number
}

Rules for dismissal (seconds):

  • Not provided: default system retention (up to 4 hours)
  • <= 0: remove immediately
  • > 0: remove after the specified interval

7.4 Reading Activity State

getActivityState(): Promise<LiveActivityState | null>

7.5 Listening for State Changes

addUpdateListener(listener);
removeUpdateListener(listener);

Triggered when the Live Activity transitions between:

  • active → stale
  • active → ended
  • ended → dismissed

7.6 Static Methods

static areActivitiesEnabled(): Promise<boolean>
static getAllActivities(): Promise<LiveActivityDetail[]>
static getAllActivitiesIds(): Promise<string[]>
static getActivityState(activityId: string)
static from(activityId, name)
static endAllActivities(options?)

8. UI Components for Expanded Layout

ComponentDescription
LiveActivityUIRoot layout container
LiveActivityUIExpandedLeadingLeading region of expanded layout
LiveActivityUIExpandedTrailingTrailing region
LiveActivityUIExpandedCenterCenter region
LiveActivityUIExpandedBottomBottom region

These components help structure the expanded Dynamic Island.


9. Best Practices

9.1 contentState must be JSON-serializable

The following are not allowed:

  • Functions
  • Date objects (must use timestamps)
  • Class instances
  • Non-serializable structures

9.2 Live Activity registration must be in a standalone file

This is required due to UI compilation and ActivityKit rules.

9.3 Live Activities survive script termination

If your script needs to keep running (e.g., timers), use:

BackgroundKeeper.keepAlive();

10. Minimal Example

const activity = MyLiveActivity();

await activity.start({ mins: 10 });

await activity.update({ mins: 5 });

await activity.end({ mins: 0 }, { dismissTimeInterval: 0 });

11. Notes

  • Live Activity starts asynchronously. You need to wait for start to return true before calling update and end.
  • Live Activity cannot access documents and iCloud directories. If you want to access files or render images, you must save them to FileManager.appGroupDocumentsDirectory. For example, to render an image, you save it to FileManager.appGroupDocumentsDirectory, then use <Image filePath={Path.join(FileManager.appGroupDocumentsDirectory, 'example.png')} /> to render it.
  • Live Activity can access the Storage data shared with the app.