How to properly adapt regular JS code to the requirements of React Native? What should be considered?

Question

JavaScript

There is a JS code that works on a page opened in WebView and operates with data about location, speed, etc. For some reason, this code needs to be translated directly into React Native itself. As far as I can see, React Native has a slightly different syntax. What should be considered in such a transition?

Answer 1

Somewhat blurry.
What would I do.
The task is to preserve the code as much as possible in the form in which it is written under the Web.
1) If you need to transfer the UI, then this part will have to be rewritten.
2) Geolocation. Let's imagine that the access to it differs greatly in syntax and the data is returned in a different form.
Then we include the library in a separate file and write a wrapper class that will make the necessary requests and return the answer in the right form for the code from the web.
Hypothetical example.
On the Web the syntax is:

GEO.getLocation(function(result){

});

And on React Native:

let geo = await System.getGeo();
let location = await geo.getLocation();

How can you adapt:

class Geo {
    static async getLocation(callback) {
        try {
            let geo = await System.getGeo();
            callback(await geo.getLocation());
        } catch(e) {}
       
        geo = null;

    }

}

With this example, I wanted to show that the implementation difference can be hidden by a wrapper class.