/react-native

name: react-native
description: React Native renderer for json-render that turns JSON specs into native mobile UIs. Use when working with @json-render/react-native, building React Native UIs from JSON, creating mobile component catalogs, or rendering AI-generated specs on mobile.

@json-render/react-native

React Native renderer that converts JSON specs into native mobile component trees with standard components, data binding, visibility, actions, and dynamic props.

Quick Start

import { defineCatalog } from "@json-render/core";
import { schema } from "@json-render/react-native/schema";
import {
  standardComponentDefinitions,
  standardActionDefinitions,
} from "@json-render/react-native/catalog";
import { defineRegistry, Renderer, type Components } from "@json-render/react-native";
import { z } from "zod";

// Create catalog with standard + custom components
const catalog = defineCatalog(schema, {
  components: {
    ...standardComponentDefinitions,
    Icon: {
      props: z.object({ name: z.string(), size: z.number().nullable(), color: z.string().nullable() }),
      slots: [],
      description: "Icon display",
    },
  },
  actions: standardActionDefinitions,
});

// Register only custom components (standard ones are built-in)
const { registry } = defineRegistry(catalog, {
  components: {
    Icon: ({ props }) => <Ionicons name={props.name} size={props.size ?? 24} />,
  } as Components<typeof catalog>,
});

// Render
function App({ spec }) {
  return (
    <StateProvider initialState={{}}>
      <VisibilityProvider>
        <ActionProvider handlers={{}}>
          <Renderer spec={spec} registry={registry} />
        </ActionProvider>
      </VisibilityProvider>
    </StateProvider>
  );
}

Standard Components

Layout

• `Container` - wrapper with padding, background, border radius
• `Row` - horizontal flex layout with gap, alignment
• `Column` - vertical flex layout with gap, alignment
• `ScrollContainer` - scrollable area (vertical or horizontal)
• `SafeArea` - safe area insets for notch/home indicator
• `Pressable` - touchable wrapper that triggers actions on press
• `Spacer` - fixed or flexible spacing
• `Divider` - thin line separator

Content

• `Heading` - heading text (levels 1-6)
• `Paragraph` - body text
• `Label` - small label text
• `Image` - image display with sizing modes
• `Avatar` - circular avatar image
• `Badge` - small status badge
• `Chip` - tag/chip for categories

Input

• `Button` - pressable button with variants
• `TextInput` - text input field
• `Switch` - toggle switch
• `Checkbox` - checkbox with label
• `Slider` - range slider
• `SearchBar` - search input

Feedback

• `Spinner` - loading indicator
• `ProgressBar` - progress indicator

Composite

• `Card` - card container with optional header
• `ListItem` - list row with title, subtitle, accessory
• `Modal` - bottom sheet modal

Visibility Conditions

Use `visible` on elements. Syntax: `{ "$state": "/path" }`, `{ "$state": "/path", "eq": value }`, `{ "$state": "/path", "not": true }`, `[ cond1, cond2 ]` for AND.

Pressable + setState Pattern

Use `Pressable` with the built-in `setState` action for interactive UIs like tab bars:

{
  "type": "Pressable",
  "props": {
    "action": "setState",
    "actionParams": { "statePath": "/activeTab", "value": "home" }
  },
  "children": ["home-icon", "home-label"]
}

Dynamic Prop Expressions

Any prop value can be a data-driven expression resolved at render time:

• **`{ "$state": "/state/key" }`** - reads from state model (one-way read)
• **`{ "$bindState": "/path" }`** - two-way binding: use on the natural value prop (value, checked, pressed, etc.) of form components.
• **`{ "$bindItem": "field" }`** - two-way binding to a repeat item field. Use inside repeat scopes.
• **`{ "$cond": <condition>, "$then": <value>, "$else": <value> }`** - conditional value

{
  "type": "TextInput",
  "props": {
    "value": { "$bindState": "/form/email" },
    "placeholder": "Email"
  }
}

Components do not use a `statePath` prop for two-way binding. Use `{ "$bindState": "/path" }` on the natural value prop instead.

Built-in Actions

The `setState` action is handled automatically by `ActionProvider` and updates the state model directly, which re-evaluates visibility conditions and dynamic prop expressions:

{ "action": "setState", "actionParams": { "statePath": "/activeTab", "value": "home" } }

Providers

| Provider | Purpose | |----------|---------| | `StateProvider` | Share state across components (JSON Pointer paths). Accepts optional `store` prop for controlled mode. | | `ActionProvider` | Handle actions dispatched from components | | `VisibilityProvider` | Enable conditional rendering based on state | | `ValidationProvider` | Form field validation |

External Store (Controlled Mode)

Pass a `StateStore` to `StateProvider` (or `JSONUIProvider` / `createRenderer`) to use external state management:

import { createStateStore, type StateStore } from "@json-render/react-native";

const store = createStateStore({ count: 0 });

<StateProvider store={store}>{children}</StateProvider>

store.set("/count", 1); // React re-renders automatically

When `store` is provided, `initialState` and `onStateChange` are ignored.

Key Exports

| Export | Purpose | |--------|---------| | `defineRegistry` | Create a type-safe component registry from a catalog | | `Renderer` | Render a spec using a registry | | `schema` | React Native element tree schema | | `standardComponentDefinitions` | Catalog definitions for all standard components | | `standardActionDefinitions` | Catalog definitions for standard actions | | `standardComponents` | Pre-built component implementations | | `createStandardActionHandlers` | Create handlers for standard actions | | `useStateStore` | Access state context | | `useStateValue` | Get single value from state | | `useBoundProp` | Two-way state binding via `$