Filling form fields of a webpage opened in a web view with React Native - react-native

Question

I'm working on a project that includes a module that helps with electricity recharge, so what happens is that the user's data is already saved in the app and when they choose to recharge, the app opens up this webpage in a web view.
Currently, I'm using WebBridgeView for opening the webpage as:-
render() {
return (
<WebViewBridge
ref="webviewbridge"
onBridgeMessage={this.onBridgeMessage.bind(this)}
source={{uri: "https://currencypin.com/PrepaidMeterPaymentsV2.0/cartwiz?c=IN&p=5&pm=tm"}}/>
);
}
}
Now, what I want is that when the webpage opens, the form fields come prefilled with the custom data that I have. So that the only field that the user needs to fill on the page is the CAPTCHA.
I was following this article for achieving the same, but it actually assumes that the website is customizable. Which is not possible in my case because it belongs to a 3rd party vendor.
What are the ways to achieve this?

Answer 1

You have to use the injectedJavaScript prop from WebView.
First declare a jsCode variable:
const amount = 2
const jscode = `
if (document.getElementById('txtAmount') == null) {
// field not existing, deal with the error
} else {
document.getElementById('txtAmount').value = '${amount}';
}
`
Please notice the " ` " character. Used to put variables in strings.
Then use it like so:
<WebViewBridge
ref="webviewbridge"
onBridgeMessage={this.onBridgeMessage.bind(this)}
injectedJavaScript={jsCode}