This is a hacky way to do it, while we wait for a native bridge (I found it in a React Native issue on GitHub.
https://github.com/facebook/react-native/issues/586#issuecomment-90826117
Basically you trigger an event in your parent component by listening to a navigation change in the WebView, and pass the name of a method (or whatever) via the document.title field.
Longer post coming (maybe, I find myself adding stuff on the go 😰)
You will also have to read the following to correctly send all the data you want from the WebView to the parent component.
