got 2 ways to work

examples/rpc/index.ios.js

@@ -18,8 +18,8 @@ const injectScript = `
   (function () {
     if (window.WebViewBridge) {
 
-      WebViewBridge.addMessageListener(function (message) {
-        alert(message)
+      WebViewBridge.addMessageListener(function (payload) {
+        alert(payload.message)
       });
 
       WebViewBridge.send({ message: 'This is working' });
@@ -29,12 +29,16 @@ const injectScript = `
 
 class rpc extends Component {
   onMessage = (payload) => {
-    console.log(payload.message)
+    if (this.bridgeRef) {
+      console.log(payload.message)
+      this.bridgeRef.sendToBridge({ message: 'This is working too' })
+    }
   }
+
   render() {
-    console.log(injectScript)
     return (
       <WebView
+        ref={(ref) => this.bridgeRef = ref}
         source={{uri: 'https://github.com/facebook/react-native'}}
         style={{marginTop: 20}}
         javaScriptEnabled={true}

webview-bridge/index.ios.js

@@ -24,7 +24,8 @@ import {
   View,
   ScrollView,
   NativeModules,
-  requireNativeComponent
+  requireNativeComponent,
+  findNodeHandle
 } from 'react-native'
 
 import invariant from 'fbjs/lib/invariant'
@@ -495,7 +496,7 @@ class WebView extends React.Component {
    * Returns the native `WebView` node.
    */
   getWebViewHandle = (): any => {
-    return ReactNative.findNodeHandle(this.refs[RCT_WEBVIEW_REF]);
+    return findNodeHandle(this.refs[RCT_WEBVIEW_REF]);
   };
 
   _onLoadingStart = (event: Event) => {