const dataArray = [{key: 0,id: 'A',},{key: 1,id: 'B',},{key: 2,id: 'Z',}]

// Root Component
export default class App extends Component {
    render(){
        return (
            <View>
            {this.getSomeText()}
            </
    getSomeText() {
        return dataArray.map( d =>
            <SomeText key={d.key} id={d.id} onLayout={(e) => this.onLayout(e)} />
        )
    }
    onLayout (e, id ) {
        // add these items to array
        // e.nativeEvent.Layout{Width,Height,x,y,id}
        // I can add the e data but the id data never comes through.
    }
}


// Child Component
class SomeText extends Component {
    render() {
        return (
            <Text
                onLayout={this.props.onLayout}
                // onLayout as above this returns the event e but
                // 2. this.props.onLayout() // doesn't return e at all ??
                // 3. () => this.props.onLayout // doesn't work either, why?
                // 4. (e, this.props.key)  => this.props.onLayout(this.props.key)
                // 4 doesnt work either
                >Some text</Text>
        )
    }
}