AppStorage

MobX-observable persistent storage backed by AsyncStorage. Properties are automatically persisted when changed.

Usage

import { createAppStorage } from '@zyno-io/mobile-foundation-rn';

// Define your storage shape with defaults
const storage = createAppStorage({
    token: undefined as string | undefined,
    onboardingComplete: false,
    preferredTheme: 'system' as 'light' | 'dark' | 'system',
});

export default storage;

// In components — MobX observer reacts to changes
import { observer } from 'mobx-react-lite';
import storage from './storage';

const ProfileScreen = observer(() => {
    return <MfText>Theme: {storage.preferredTheme}</MfText>;
});

// Set a value — auto-persisted
storage.preferredTheme = 'dark';

IMPORTANT

You must call createAppStorage() before useSetupFoundation() runs, because the setup hook calls $load() on the storage instance internally.

createAppStorage<T>(defaults?)

Creates and returns a storage instance.

Parameters

Param	Type	Description
defaults	Partial<T>	Default values for storage properties

Return Value

Returns T & AppStorageMethods — your typed properties plus the control methods.

AppStorageMethods

$load()

await storage.$load();

Loads persisted values from AsyncStorage. Called automatically by useSetupFoundation.

Memoized — subsequent calls return immediately.

$persist()

storage.$persist();

Manually trigger a persist. Normally not needed — setting any property triggers auto-persist with a 250ms debounce.

$clear()

storage.$clear();

Sets all properties to undefined and persists the cleared state.

Auto-Persistence

When you set a property on the storage object, it:

1. Updates the MobX observable (triggering observer re-renders)
2. Schedules a debounced persist (250ms) to AsyncStorage

Multiple rapid changes result in a single AsyncStorage write.

Dynamic Properties

Accessing a property that wasn't in the initial defaults auto-creates it as a MobX observable:

const storage = createAppStorage({ name: '' });

// This creates 'age' as a new observable property
storage.age = 25;