Event Handler in parent component

App.js

import React, { Component } from "react";
import ReactDOM from "react-dom";
import {
    AppProvider,
    Page,
    Card,
    Layout,
} from "@shopify/polaris";
import Wysiwyg from "./components/wysiwyg";

export default class App extends React.Component {
  
  state = {
    content: ""
  }
    
  render(){
    return(
      <AppProvider apiKey={apiKey} shopOrigin={shopOrigin} forceRedirect={true}>
        <Page>
          <Layout>
            <Card>
                <Wysiwyg onChange={this.handleContentChange} />
            </Card>
          </Layout>
         </Page>
      </AppProvider>
    );
  }


  handleContentChange = (content) => {
    this.setState({content : content});
  };
}