injectedJavascript

// fix https://github.com/facebook/react-native/issues/10865
// MrLoh
const patchPostMessageJsCode = `(${String(function() {
    throw new Error;  // Doesn't get triggered
    var originalPostMessage = window.postMessage
    var patchedPostMessage = function(message, targetOrigin, transfer) {
        originalPostMessage(message, targetOrigin, transfer)
    }
    patchedPostMessage.toString = function() {
        return String(Object.hasOwnProperty).replace('hasOwnProperty', 'postMessage')
    }
    window.postMessage = patchedPostMessage
    setTimeout(function () {window.postMessage( "my message", "*" );}, 2000);
    throw new Error
})})();`


class JourneyVid extends Component {
    state = {debug: null}

    postMessage = (action) => {
        // throw new Error  // Works fine too
        this.webView.postMessage("my other message", "*");
    }

    onMessage = (evnt) => {
        throw new Error;  // Doesn't get triggered
        var dataStr = JSON.parse( evnt.nativeEvent.data );
        this.setState({ debug: dataStr });
    }

    render () {
        // throw new Error  // works just fine
        count++

        var style           = {...styles.vid, backgroundColor: color, flex: 1, display: 'flex'},
            color           = this.props.color || 'red',
            debugContent    = null;

        if (this.state.debug !== null) {
          debugContent = <Text>{ this.state.debug }</Text>;  // Doesn't ever seem to show anything
          style.backgroundColor = 'blue';
        }

        return (
            <View style={style}>
                <WebView style={{flex: 1}}
                    ref={thsiRef => {this.webView = thsiRef}}
                    automaticallyAdjustContentInsets={true}
                    source={{uri: 'https://myURL.com'}}
                    javaScriptEnabled={true}
                    javaScriptEnabledAndroid={true}
                    domStorageEnabled={true}
                    decelerationRate='normal'
                    startInLoadingState={true}
                    allowsInlineMediaPlayback={false}
                    onMessage={this.onMessage}
                    injectedJavascript={patchPostMessageJsCode} />
                <TouchableOpacity onPress={this.postMessage}>
                    <Text>Send message from react native</Text>
                </TouchableOpacity>
                { debugContent }
            </View>
        );
    }
};