Using React Native Methods in Web

This guide covers how to use methods declared in React Native within a web.

React Native Part

Register functions in the bridge object in your React Native code

IMPORTANT

You need to export the created typeof appBridge and share its type with the web project. Failing to do so will result in a lack of type safety. This principle is similar to how tRPC operates.

For detailed guides, visit:
Monorepo setup: Exporting Type Declarations in a Monorepo
Custom declaration file: Exporting Type Declarations with a Custom Declaration File
Generate declaration file: Exporting Type Declarations with a Generate Declaration File

import { createWebView, bridge } from "@webview-bridge/react-native";
import InAppBrowser from "react-native-inappbrowser-reborn";

// Register functions in the bridge object in your React Native code
export const appBridge = bridge({
  async getMessage() {
    return "Hello, I'm native";
  },
  async sum(a: number, b: number) {
    return a + b;
  },
  async openInAppBrowser(url: string) {
    if (await InAppBrowser.isAvailable()) {
      await InAppBrowser.open(url);
    }
  },
  // ... Add more functions as needed
});

// Export the bridge type to be used in the web application
export type AppBridge = typeof appBridge;

Create a WebView Component by combining the previously defined bridge with createWebView.

NOTE

The WebView created through createWebView is identical to the typical react-native-webview.

export const { WebView } = createWebView({
  bridge: appBridge,
  debug: true, // Enable console.log visibility in the native WebView
});

// Use the WebView component in your app
function App(): JSX.Element {
  return (
    <SafeAreaView style={{ height: "100%" }}>
      <WebView
        source={{
          uri: "http://localhost:5173",
        }}
        style={{ height: "100%", flex: 1, width: "100%" }}
      />
    </SafeAreaView>
  );
}

export default App;

Web Part

Now, let's setting up the web project that will be displayed in the WebView. Utilize the previously exported AppBridge as a generic in linkBridge.

That's all there is to it!

You can directly use bridge as shown below and receive the results.

import { linkBridge } from "@webview-bridge/web";
import type { AppBridge } from ""; // Import the type 'appBridge' declared in native

const bridge = linkBridge<AppBridge>({
  onReady: async (method) => {
    console.log("bridge is ready");
    const version = await method.getBridgeVersion();
    console.log("currentBridgerVersion", version);
  },
});

bridge.getMessage().then((message) => console.log(message)); // Expecting "Hello, I'm native"
bridge.sum(1, 2).then((num) => console.log(num)); // Expecting 3
bridge.openInAppBrowser("https://google.com"); // Open google in the native inAppBrowser

Checking WebView Bridge Availability

You can also check for the availability of specific methods using isNativeMethodAvailable.

This allows you to safely execute methods only when they are available. Here's how you can implement this:

if (bridge.isNativeMethodAvailable("openInAppBrowser")) {
    bridge.openInAppBrowser();
} else {
    console.warn("openInAppBrowser method not supported");
}

In addition, to check the general availability of the WebView bridge, you can use isWebViewBridgeAvailable:

if (bridge.isWebViewBridgeAvailable) {
    bridge.openInAppBrowser();
} else {
    console.warn("native method not supported")
}