Set user agent with WebView with react-native

Question

I want to modify the user agent string in a WebView so that on the server side I can detect that the request has come from my react-native app. I want to do this using the source prop in the WebView.

How do I do this for IOS and Android?

Answer 1

You just can set it as a prop in your WebView.

I'm doing the following:

on iOS (I set the userAgent in AppDelegate.m)

NSString *deviceType = [UIDevice currentDevice].model;
UIWebView *webView = [[UIWebView alloc] initWithFrame:CGRectZero];
NSString *oldAgent = [webView stringByEvaluatingJavaScriptFromString:@"navigator.userAgent"];
NSString *newAgent = [oldAgent stringByAppendingString:@" MYAPPNAME - iOS - "];
newAgent = [newAgent stringByAppendingString:deviceType];
NSDictionary *dictionnary = [[NSDictionary alloc] initWithObjectsAndKeys:newAgent, @"UserAgent", nil];
[[NSUserDefaults standardUserDefaults] registerDefaults:dictionnary];

on Android (I set the userAgent in JS in my WebView):

<WebView
    userAgent={DeviceInfo.getUserAgent() + " - MYAPPNAME - android "}   
    ref={"WEBVIEW"}
    automaticallyAdjustContentInsets={false}
    source={{uri: this.state.url}} />

now I'm always having a userAgent like "DeviceInfo - MYAPPNAME - Platform". We're doing the same like you and it works how it's supposed to do.

Answer 2

For Android, you only need to set userAgent attribute, for example:

<WebView
source={{ uri: "https://stackoverflow.com" }}
userAgent="Mozilla/5.0 (Windows NT 6.1) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/67.0.3396.99 Safari/537.36"
 />

For iOS, you need to add the code below inside the method didFinishLaunchingWithOptions (before the line return YES; ) in AppDelegate.m implementation:

NSString *userAgent = @"Mozilla/5.0 (Macintosh; Intel Mac OS X 10_13_4) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/67.0.3396.99 Safari/537.36";
NSDictionary *dictionary = [[NSDictionary alloc] initWithObjectsAndKeys:userAgent, @"UserAgent", nil];
[[NSUserDefaults standardUserDefaults] registerDefaults:dictionary];

Answer 3

This library now provides a method to get the userAgent for both ios and android:

https://github.com/react-native-community/react-native-device-info#getuseragent

this.state = { 
   userAgent: "",
}

componentDidMount = async () => {
   this.setState({ userAgent: await DeviceInfo.getUserAgent() })
}

<WebView
source={{ uri: "https://stackoverflow.com" }}
userAgent={this.state.userAgent}
>

Answer 4

windows phone user-agent for android and ios

Android:

mWebView.getSettings().setUserAgentString("Mozilla/5.0 (compatible; MSIE 10.0; Windows Phone 8.0; Trident/6.0; IEMobile/10.0; ARM; Touch; NOKIA; Lumia 920)");

IOS:

[[NSUserDefaults standardUserDefaults] registerDefaults:[NSDictionary dictionaryWithObject:@"Mozilla/5.0 (compatible; MSIE 10.0; Windows Phone 8.0; Trident/6.0; IEMobile/10.0; ARM; Touch; NOKIA; Lumia 920)" forkey:@"UserAgent"]];

Answer 5

just add this to user agent you can update the versions in future, I used is as google login was giving me issue

userAgent="Mozilla/5.0 (Linux; Android 10; Android SDK built for x86 Build/LMY48X) AppleWebKit/537.36 (KHTML, like Gecko) Version/4.0 Chrome/81.0.4044.117 Mobile Safari/608.2.11"

Answer 6

This is not an answer, but a workaround.

I realised that what I wanted to do was determine if a request to my ruby on rails server was from mobile safari or from the webView of my react-native app. To solve this, I just installed the browser gem, and then did

browser = Browser.new(request.user_agent)
from_app = browser.platform.ios_webview?

If someone can give a clear answer to my original question, I will select that answer rather than mine.

Answer 7

For iOS, you can use WKWebView instead of WebView which support userAgent setting. https://github.com/react-native-community/react-native-webview/blob/master/docs/Reference.md#useragent

Answer 8

- (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions
{

NSDictionary *dictionary = [NSDictionary dictionaryWithObjectsAndKeys:@"Mozilla/5.0 (Windows NT 6.1) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/41.0.2228.0 Safari/537.36", @"UserAgent", nil];
 [[NSUserDefaults standardUserDefaults] registerDefaults:dictionary];

}

Answer 9

This is a terrible idea. Just use a custom header:

X-MY-CUSTOM-HEADER = MyAppName.