@rbxts/react

TypeScript type definitions for React Lua.
npm package →

TypeScript type definitions for React Lua and roblox-ts, sourced from the official React types. Currently, only @rbxts/react and @rbxts/react-roblox may be installed.

If we're missing any deviations from React Lua, please open an issue or pull request to let us know!

If you're encountering issues with @rbxts/react, please see the Troubleshooting section for more information.

[!IMPORTANT] This package requires roblox-ts version 3.0 or later. If you're using an older version of roblox-ts, you'll need to update to the latest version.

📦 Setup

Installation

Get started by installing @rbxts/react and @rbxts/react-roblox:

npm install @rbxts/react @rbxts/react-roblox
yarn add @rbxts/react @rbxts/react-roblox
pnpm add @rbxts/react @rbxts/react-roblox # 🔴 See below

Configuration

Set up your tsconfig.json JSX options to use React's createElement and Fragment:

"compilerOptions": {
  "jsxFactory": "React.createElement",
  "jsxFragmentFactory": "React.Fragment"
}

Usage with PNPM

If you're using PNPM as your package manager, you'll need to create a .npmrc file in the root of your project with the following content:

node-linker=hoisted

🚀 Examples

Mounting your app

import React, { StrictMode } from "@rbxts/react";
import { createPortal, createRoot } from "@rbxts/react-roblox";

const root = createRoot(new Instance("Folder"));

root.render(<StrictMode>{createPortal(<App />, playerGui)}</StrictMode>);

Function Component

import React, { useState } from "@rbxts/react";

interface CounterProps {
	initialCount: number;
}

export function Counter({ initialCount }: CounterProps) {
	const [count, setCount] = useState(initialCount);

	return (
		<textbutton
			Text={`Count: ${count}`}
			AnchorPoint={new Vector2(0.5, 0.5)}
			Size={new UDim2(0, 100, 0, 50)}
			Position={new UDim2(0.5, 0, 0.5, 0)}
			Event={{
				Activated: () => setCount(count + 1),
			}}
		/>
	);
}

Class Component

import React, { Component, ReactComponent } from "@rbxts/react";

interface CounterProps {
	initialCount: number;
}

interface CounterState {
	count: number;
}

@ReactComponent
export class Counter extends Component<CounterProps, CounterState> {
	state: CounterState = {
		count: this.props.initialCount,
	};

	render() {
		return (
			<textbutton
				Text={`Count: ${this.state.count}`}
				AnchorPoint={new Vector2(0.5, 0.5)}
				Size={new UDim2(0, 100, 0, 50)}
				Position={new UDim2(0.5, 0, 0.5, 0)}
				Event={{
					Activated: () => this.setState({ count: this.state.count + 1 }),
				}}
			/>
		);
	}
}

Error Boundary

import React, { Component, ErrorInfo, ReactComponent } from "@rbxts/react";

interface ErrorBoundaryProps {
	fallback: (error: unknown) => React.Element;
}

interface ErrorBoundaryState {
	hasError: boolean;
	message?: unknown;
}

@ReactComponent
export class ErrorBoundary extends Component<ErrorBoundaryProps, ErrorBoundaryState> {
	state: ErrorBoundaryState = {
		hasError: false,
	};

	componentDidCatch(message: unknown, info: ErrorInfo) {
		warn(message, info.componentStack);

		this.setState({
			hasError: true,
			message: `${message} ${info.componentStack}`,
		});
	}

	render() {
		if (this.state.hasError) {
			return this.props.fallback(this.state.message);
		} else {
			return this.props.children;
		}
	}
}

🔎 Troubleshooting

compilerOptions.jsxFactory must be Roact.createElement!

If you encounter this error during compilation, it means that you're using an older version of roblox-ts. Make sure to install the latest version of roblox-ts and remove any global installations:

npm uninstall -g roblox-ts
npm install -D roblox-ts@latest

nil cannot be used as a JSX component.

This error typically occurs when tsconfig.json has not been configured correctly. Make sure that your fragment factory is set to React.Fragment, and that your JSX factory is set to React.createElement:

"compilerOptions": {
  "jsxFactory": "React.createElement",
  "jsxFragmentFactory": "React.Fragment"
}

(X) cannot be used as a JSX component. Its return type Element is not a valid JSX element.

This error can occur when a conflicting installation of react-ts is present in your project. This can be for one of two reasons:

1. You have react-ts installed in your dependencies. (npm uninstall @rbxts/roact)
2. You have an outdated package installed that depends on react-ts.

The most common cause is an outdated package. To view the packages that depend on @rbxts/react-ts (which will be under the alias @rbxts/roact), run the following command:

npm ls @rbxts/roact

If you find any packages that depend on @rbxts/react-ts, you should update them to the latest version, or open an issue on their repository to request an update.

Attempt to index nil with useMemo (or other hooks)

This error happens when a hook was called in an invalid environment. There are two common reasons for this error:

1. You're using a hook outside of a component, or using function components incorrectly.

Hooks must be used inside the body of a function component. A common mistake is to call hooks conditionally, or inside a callback function. Make sure you're calling hooks at the top level of your function component.

Do not call a function component directly. To render a function component, wrap it in a JSX tag:

<App />; // 🟢 Good
App(); // 🔴 Bad

2. There's more than one version of React in your project.

When multiple versions of React are present in your node_modules, your packages might import hooks from the wrong version of React. Update your packages to the latest version that supports @rbxts/react, or remove the conflicting packages.

If you have no conflicting dependencies, or a fresh install doesn't remove the outdated package, see the previous section for more information.

My issue isn't listed here!

If you're encountering an issue that isn't listed here, please post your issue in the roblox-ts Discord server.

📚 Resources

• React Documentation - Learn about React's core concepts and API
• React Lua Documentation - A comprehensive guide for the differences between Roact and React
• JS.Lua Repository - The source code for React Lua

📝 License

This project is licensed under the MIT license.