window.ReactNativeWebView.postMessage causes error on webview side

##VERSION

"dependencies": {
    "react": "16.6.3",
    "react-native": "0.58.1",
    "react-native-webview": "git+https://github.com/react-native-community/react-native-webview.git",
  },

I’m using laravel php framework for Webview side which is located on localhost. The communication between react native side and webview are all fine. But I got this error when opened website with PC browser. ReactNativeWebViewBridge.js:91 rnBridge send failed Cannot read property 'postMessage' of undefined

This is source code on webview side

....
var msgObj = {
                   targetFunc: targetFunc,
                   data: data || {},
                   msgId: guid(),
               };

               var msg = JSON.stringify(msgObj);

               promiseChain = promiseChain.then(function () {
                   return new Promise(function (resolve, reject) {
                       console.log("sending message " + msgObj.targetFunc);

                       promises[msgObj.msgId] = {resolve: resolve, reject: reject};
                       callbacks[msgObj.msgId] = {
                           onsuccess: success,
                           onerror: error
                       };

                       window.ReactNativeWebView.postMessage(msg);  // For react-native-webview
                   })
               }).catch(function (e) {
                   console.error('rnBridge send failed ' + e.message);
               });
....

Source for native side

return (
	      	<SafeAreaView style={styles.container}>
		        <WebView
		        	ref={webview => {this.myWebView = webview;}}
			        useWebKit={true}	// WKWebView
			        source={{uri: URL_HOME}}
			        javaScriptEnabled={true}
			        cacheEnabled={false}
			        startInLoadingState={true}
			        onMessage={this.onWebViewMessage}
		       />
            />
	       	</SafeAreaView>
	    );

How to remove this error ?

I tried using window.postMessage(msg, "*"); and then injectedJavaScript with

const injectedJavascript = `(function() {
  window.postMessage = function(data) {
    window.ReactNativeWebView.postMessage(data);
  };
})()`;

but the communication of react native and webview did not work.