react-native-webview/docs/Guide.md

React Native WebView Guide

This document walks you through the most common use cases for React Native WebView. It doesn’t cover the full API, but after reading it and looking at the sample code snippets you should have a good sense for how the WebView works and common patterns for using the WebView.

This guide is currently a work in progress.

Guide Index

• Basic Inline HTML
• Basic URL Source

Basic inline HTML

The simplest way to use the WebView is to simply pipe in the HTML you want to display. Note that setting an html source requires the originWhiteList property to be set to ['*'].

import React, { Component } from 'react';
import { WebView } from 'react-native-webview';

class MyInlineWeb extends Component {
  render() {
    return (
      <WebView
        originWhitelist={['*']}
        source={{ html: '<h1>This is a static HTML source!</h1>' }}
      />
    );
  }
}

Passing a new static html source will cause the WebView to rerender.

Basic URL Source

This is the most common use-case for WebView.

import React, { Component } from 'react';
import { WebView } from 'react-native-webview';

class MyWeb extends Component {
  render() {
    return (
      <WebView
        source={{uri: 'https://infinite.red/react-native'}}
      />
    );
  }
}

Controlling navigation state changes

Sometimes you want to intercept a user tapping on a link in your webview and do something different than navigating there in the webview. Here’s some example code on how you might do that using the onNavigationStateChange function.

import React, { Component } from 'react';
import { WebView } from 'react-native-webview';

class MyWeb extends Component {
  webview = null;

  render() {
    return (
      <WebView
        ref={ref => (this.webview = ref)}
        source={{uri: 'https://infinite.red/react-native'}}
        onNavigationStateChange={this.handleWebViewNavigationStateChange}
      />
    );
  }

  handleWebViewNavigationStateChange = newNavState => {
    // newNavState looks something like this:
    // {
    //   url?: string;
    //   title?: string;
    //   loading?: boolean;
    //   canGoBack?: boolean;
    //   canGoForward?: boolean;
    // }
    const { url } = newNavState;
    if (!url) return

    // handle certain doctypes
    if (url.includes('.pdf')) {
      this.webview.stopLoading();
      // open a modal with the PDF viewer
    }

    // one way to handle a successful form submit is via query strings
    if (url.includes('?message=success')) {
      this.webview.stopLoading();
      // maybe close this view?
    }

    // one way to handle errors is via query string
    if (url.includes('?errors=true')) {
      this.webview.stopLoading();
    }

    // redirect somewhere else
    if (url.includes('google.com')) {
      const newURL = 'https://infinite.red';
      const redirectTo = 'window.location = "' + newURL + '"';
      this.webview.injectJavaScript(redirectTo);
    }
  }
}