Home Web Front-end JS Tutorial About communication between react native and webview

About communication between react native and webview

Feb 01, 2018 pm 01:17 PM
native react webview

WebView is a component in ReactNative. It can create a native WebView and can be used to access a web page. This article mainly introduces the sample code for communication between react native and webview. The editor thinks it is quite good, so I will share it with you now. , also as a reference for everyone. Let’s follow the editor to take a look, I hope it can help everyone.

Sometimes we need to communicate between RN and WebView, or transfer data, or send message notifications. At this time, we need to use the following knowledge.

1: WebView sends data to RN:

First, we build a webview:


##

<WebView
  ref={&#39;webview&#39;}
  source={require(&#39;./index.html&#39;)}
  style={{width: 375, height: 220}}
  onMessage={(e) => {
    this.handleMessage(e)
  }}
  
/>
Copy after login

You can see that there is an onMessage method,


onMessage function

The function corresponding to this attribute can be triggered when the window.postMessage method is called in the webpage inside the webview, thus Realize data exchange between web page and RN. When setting this property, a postMessage global function will be injected into the webview and override the implementation of the same name that may already exist.

Window.postMessage on the web page only sends one parameter data, which is encapsulated in the event object on the RN side, namely event.nativeEvent.data. data can only be a string.

It can be seen that this method is used to receive data from Webview (that is, html).


The internal implementation is to process the received data:



handleMessage(e) {
  this.setState({webViewData: e.nativeEvent.data});
}
Copy after login

e.nativeEvent.data is the data sent from inside the webview.


Just doing this is not enough, this is just For Rn side processing, we also need to write a method of sending data in html:



var data = 0;

function sendData(data) {
  if (window.originalPostMessage) {
    window.postMessage(data);
  } else {
    throw Error(&#39;postMessage接口还未注入&#39;);
  }
}
document.getElementById(&#39;button&#39;).onclick = function () {
  data += 100;
  sendData(data);
}
Copy after login

window.postMessage is to send data to RN.

Two: RN sends data to Webview:

First define a method to send data:



sendMessage() {
  this.refs.webview.postMessage(++this.data);
}
Copy after login

This step is very simple.

Just write the data you want to send as a parameter in this method.

Then, there must also be a corresponding method for receiving data in the html:



window.onload = function () {
  document.addEventListener(&#39;message&#39;, function (e) {
    document.getElementById(&#39;data&#39;).textContent = e.data;
  });

}
Copy after login

This enables communication between Rn and Webview.


Put the source code afterwards:



<!DOCTYPE html>
<html lang="en">
<head>
  <title></title>
  <meta charset="UTF-8">
  <meta name="viewport" content="width=device-width, initial-scale=1">
</head>
<body>
<p style="text-align: center">
  <button id="button">发送数据到react native</button>
  <p style="text-align: center">收到react native发送的数据: <span id="data"></span></p>
</p>
<script>
  var data = 0;

  function sendData(data) {
    if (window.originalPostMessage) {
      window.postMessage(data);
    } else {
      throw Error(&#39;postMessage接口还未注入&#39;);
    }
  }

  window.onload = function () {
    document.addEventListener(&#39;message&#39;, function (e) {
      document.getElementById(&#39;data&#39;).textContent = e.data;
    });
    document.getElementById(&#39;button&#39;).onclick = function () {
      data += 100;
      sendData(data);
    }
  }
</script>
</body>
</html>
Copy after login

web.js:


##

/**
 * Created by 卓原 on 2017/8/17.
 * zhuoyuan93@gmail.com
 */
import React from &#39;react&#39;;
import {
  View,
  Text,
  StyleSheet,
  WebView
} from &#39;react-native&#39;;

export default class Web extends React.Component {

  constructor(props) {
    super(props);
    this.state = {
      webViewData: &#39;&#39;
    }
    this.data = 0;
  }

  sendMessage() {
    this.refs.webview.postMessage(++this.data);
  }

  handleMessage(e) {
    this.setState({webViewData: e.nativeEvent.data});
  }

  render() {
    return (
      <View style={styles.container}>
        <View style={{width: 375, height: 220}}>
          <WebView
            ref={&#39;webview&#39;}
            source={require(&#39;./index.html&#39;)}
            style={{width: 375, height: 220}}
            onMessage={(e) => {
              this.handleMessage(e)
            }}

          />

        </View>
        <Text>来自webview的数据 : {this.state.webViewData}</Text>
        <Text onPress={() => {
          this.sendMessage()
        }}>发送数据到WebView</Text>
      </View>
    )
  }
}

const styles = StyleSheet.create({
  container: {
    flex: 1,
    marginTop: 22,
    backgroundColor: &#39;#F5FCFF&#39;,
  },

});
Copy after login

Related recommendations:


JS Interactively click on the picture in WKWebView and preview the example

Detailed explanation of WebView knowledge points

Detailed explanation of the method of loading HTML code using WebView

The above is the detailed content of About communication between react native and webview. For more information, please follow other related articles on the PHP Chinese website!

Statement of this Website
The content of this article is voluntarily contributed by netizens, and the copyright belongs to the original author. This site does not assume corresponding legal responsibility. If you find any content suspected of plagiarism or infringement, please contact admin@php.cn

Hot AI Tools

Undresser.AI Undress

Undresser.AI Undress

AI-powered app for creating realistic nude photos

AI Clothes Remover

AI Clothes Remover

Online AI tool for removing clothes from photos.

Undress AI Tool

Undress AI Tool

Undress images for free

Clothoff.io

Clothoff.io

AI clothes remover

Video Face Swap

Video Face Swap

Swap faces in any video effortlessly with our completely free AI face swap tool!

Hot Tools

Notepad++7.3.1

Notepad++7.3.1

Easy-to-use and free code editor

SublimeText3 Chinese version

SublimeText3 Chinese version

Chinese version, very easy to use

Zend Studio 13.0.1

Zend Studio 13.0.1

Powerful PHP integrated development environment

Dreamweaver CS6

Dreamweaver CS6

Visual web development tools

SublimeText3 Mac version

SublimeText3 Mac version

God-level code editing software (SublimeText3)

Hot Topics

Java Tutorial
1655
14
PHP Tutorial
1254
29
C# Tutorial
1228
24
How to build a reliable messaging app with React and RabbitMQ How to build a reliable messaging app with React and RabbitMQ Sep 28, 2023 pm 08:24 PM

How to build a reliable messaging application with React and RabbitMQ Introduction: Modern applications need to support reliable messaging to achieve features such as real-time updates and data synchronization. React is a popular JavaScript library for building user interfaces, while RabbitMQ is a reliable messaging middleware. This article will introduce how to combine React and RabbitMQ to build a reliable messaging application, and provide specific code examples. RabbitMQ overview:

React Router User Guide: How to implement front-end routing control React Router User Guide: How to implement front-end routing control Sep 29, 2023 pm 05:45 PM

ReactRouter User Guide: How to Implement Front-End Routing Control With the popularity of single-page applications, front-end routing has become an important part that cannot be ignored. As the most popular routing library in the React ecosystem, ReactRouter provides rich functions and easy-to-use APIs, making the implementation of front-end routing very simple and flexible. This article will introduce how to use ReactRouter and provide some specific code examples. To install ReactRouter first, we need

PHP, Vue and React: How to choose the most suitable front-end framework? PHP, Vue and React: How to choose the most suitable front-end framework? Mar 15, 2024 pm 05:48 PM

PHP, Vue and React: How to choose the most suitable front-end framework? With the continuous development of Internet technology, front-end frameworks play a vital role in Web development. PHP, Vue and React are three representative front-end frameworks, each with its own unique characteristics and advantages. When choosing which front-end framework to use, developers need to make an informed decision based on project needs, team skills, and personal preferences. This article will compare the characteristics and uses of the three front-end frameworks PHP, Vue and React.

How to use React to develop a responsive backend management system How to use React to develop a responsive backend management system Sep 28, 2023 pm 04:55 PM

How to use React to develop a responsive backend management system. With the rapid development of the Internet, more and more companies and organizations need an efficient, flexible, and easy-to-manage backend management system to handle daily operations. As one of the most popular JavaScript libraries currently, React provides a concise, efficient and maintainable way to build user interfaces. This article will introduce how to use React to develop a responsive backend management system and give specific code examples. Create a React project first

Integration of Java framework and front-end React framework Integration of Java framework and front-end React framework Jun 01, 2024 pm 03:16 PM

Integration of Java framework and React framework: Steps: Set up the back-end Java framework. Create project structure. Configure build tools. Create React applications. Write REST API endpoints. Configure the communication mechanism. Practical case (SpringBoot+React): Java code: Define RESTfulAPI controller. React code: Get and display the data returned by the API.

Vue.js vs. React: Project-Specific Considerations Vue.js vs. React: Project-Specific Considerations Apr 09, 2025 am 12:01 AM

Vue.js is suitable for small and medium-sized projects and fast iterations, while React is suitable for large and complex applications. 1) Vue.js is easy to use and is suitable for situations where the team is insufficient or the project scale is small. 2) React has a richer ecosystem and is suitable for projects with high performance and complex functional needs.

What closures does react have? What closures does react have? Oct 27, 2023 pm 03:11 PM

React has closures such as event handling functions, useEffect and useCallback, higher-order components, etc. Detailed introduction: 1. Event handling function closure: In React, when we define an event handling function in a component, the function will form a closure and can access the status and properties within the component scope. In this way, the state and properties of the component can be used in the event processing function to implement interactive logic; 2. Closures in useEffect and useCallback, etc.

React's Role in HTML: Enhancing User Experience React's Role in HTML: Enhancing User Experience Apr 09, 2025 am 12:11 AM

React combines JSX and HTML to improve user experience. 1) JSX embeds HTML to make development more intuitive. 2) The virtual DOM mechanism optimizes performance and reduces DOM operations. 3) Component-based management UI to improve maintainability. 4) State management and event processing enhance interactivity.

See all articles