have you solved it? Now I also encounter the situation that I need to adjust each other with ios. Io or Android can never be called when calling the internal methods of my react component. It seems that I can't access the internal methods of the component. They can be called if written in the index.html file. How did you solve it, please?

has not done iOS development, do not know the native details, according to your question should be able to call the JS method in WKwebview. In this way, you can bind the this scope of the React component to the callback method, and then you can access the component state on the callback method.

for example:

function callback(data){
    //  bind this 
    //  state 
    this.setState({ hello: data })
}

...

class someComponent extends React.Component {
    constructor(){
        super();
        this.state = { hello: "123" }
        callback = callback.bind(this);
    }
    ...
}