React Native comes with WebView component, which uses UIWebView on iOS. This component uses WKWebView introduced in iOS 8 with all the performance boost.
Deployment Target >= iOS 8.0 is required (which is React Native's current minimum deployment target anyway).
- Install from npm (note the postfix in the package name):
npm install react-native-wkwebview-reborn - run
react-native link react-native-wkwebview-reborn
Manual alternative
- Install from npm (note the postfix in the package name):
npm install react-native-wkwebview-reborn - In the XCode's "Project navigator", right click on your project's Libraries folder ➜ Add Files to <...>
- Go to node_modules ➜ react-native-wkwebview-reborn ➜ ios ➜ select
RCTWKWebView.xcodeproj - Go your build target ➜ Build Phases ➜ Link Binary With Libraries, click "+" and select
libRCTWkWebView.a(see the following screenshot for reference)
- Compile and profit (Remember to set Minimum Deployment Target = 8.0)
import WKWebView from 'react-native-wkwebview-reborn';Try replacing your existing WebView with WKWebView and it should work in most cases.
If your React Native < 0.40, please use 0.x.x versions.
WKWebView aims to be a drop-in replacement for UIWebView. However, some legacy UIWebView properties are not supported.
Since 1.14.0, WkWebView supports onMessage and postMessage as in the default WebView. You can refer to the React Native documentation or the example project. For advanced or customized usage, please refer to Advanced Communication between React Native and WkWebView.
- onProgress
A callback to get the loading progress of WKWebView. Derived from estimatedProgress property.
- onNavigationResponse
A callback to get response headers, http status code and http localized status code.
<WKWebView onProgress={(progress) => console.log(progress)} />progress is a double between 0 and 1.
- openNewWindowInWebView
If set to true, links with target="_blank" or window.open will be opened in the current webview, not in Safari. Default is false.
- sendCookies
Set sendCookies to true to copy cookies from sharedHTTPCookieStorage when calling loadRequest. This emulates the behavior of react-native's WebView component. You can set cookies using react-native-cookies Default is false.
- source={{file: '', allowingReadAccessToURL: '' }}
This allows WKWebView loads a local HTML file. Please note the underlying API is only introduced in iOS 9+. So in iOS 8, it will simple ignores these two properties. It allows you to provide a fallback URL for iOS 8 users.
<WKWebView source={{ file: RNFS.MainBundlePath + '/data/index.html', allowingReadAccessToURL: RNFS.MainBundlePath }} />You can also use the require syntax (sendCookies and userAgent will be ignored)
<WKWebView source={require('./index.html')} />- userAgent="MyUserAgent" (or customUserAgent="...")
Set a custom user agent for WKWebView. Note this only works on iOS 9+. Previous version will simply ignore this props.
- hideKeyboardAccessoryView
This will hide the keyboard accessory view (< > and Done). Default is false.
- allowsLinkPreview
A Boolean value that determines whether pressing on a link displays a preview of the destination for the link. This props is available on devices that support 3D Touch. In iOS 10 and later, the default value is true; before that, the default value is false.
- contentInsetAdjustmentBehavior
This property specifies how the safe area insets are used to modify the content area of the scroll view. The default value of this property is "never". Available on iOS 11 and later. Possible values are "automatic", "scrollableAxes", "never", "always". New in 1.16.0
- keyboardDisplayRequiresUserAction
Enables focusing an input inside a webview and showing the keyboard programatically. New in 1.20.0
- injectJavaScript, injectJavaScriptForMainFrameOnly
Add JavaScript at document start, see WKUserScriptInjectionTimeAtDocumentStart. New in 1.20.0
- injectedJavaScript, injectedJavaScriptForMainFrameOnly
Add JavaScript at document end. Since 1.20.0, the implementation has been changed to use WKUserScript.
- automaticallyAdjustContentInsets
- contentInset
- html (deprecated)
- injectJavaScript
- injectedJavaScript
- onError
- onLoad
- onLoadEnd
- onLoadStart
- onNavigationStateChange
- renderError
- renderLoading
- source
- startInLoadingState
- style
- url (deprecated)
- bounces
- onShouldStartLoadWithRequest
- pagingEnabled
- scrollEnabled
- directionalLockEnabled
- mediaPlaybackRequiresUserAction
- scalesPageToFit
- domStorageEnabled
- javaScriptEnabled
- allowsInlineMediaPlayback
- decelerationRate
- onMessage
This utilizes the message handlers in WKWebView and allows you to post message from webview to React Native. For example:
<WKWebView onMessage={(e) => console.log(e)} />Then in your webview, you can post message to React Native using
window.webkit.messageHandlers.reactNative.postMessage({message: 'hello!'});or (since 1.14.0)
window.postMessage({message: 'hello!'});Then you can access the nativeEvent in React Native using the event object returned
e.nativeEvent => {
name: 'reactNative',
data: {
message: 'hello!'
}
}The data serialization flow is as follows:
JS — (via WKWebView) --> ObjC --- (via React Native Bridge) ---> JS
So I recommend to keep your data simple and JSON-friendly.
There is a evaluateJavaScript method on WKWebView, which does exactly what its name suggests. To send message from React Native to WebView,
you can define a callback method on your WebView:
window.receivedMessageFromReactNative = function(data) {
// Code here
console.log(data);
}Then you can send message from React Native with this method call:
// <WKWebView ref={ref => { this.webview = ref; }} />
this.webview.evaluateJavaScript('receivedMessageFromReactNative("Hello from the other side.")');If you look at the source, the JavaScript side is mostly derived from React Native's WebView. The Objective C side mostly deals with the API difference between UIWebView and WKWebView.
We battle test this component against our app. However, we haven't use all the props so if something does not work as expected, please open an issue or PR.