JSFiddle - React, Tailwind, and code Playground

HTML

<script src="https://cdnjs.cloudflare.com/ajax/libs/knockout/3.4.1/knockout-min.js"></script>
<div data-bind="foreach: data">
  <div data-bind="text: firstName, click: $parent.selectUser">
  
  </div>
</div>

<div data-bind="text: selectedPerson">

</div>

JavaScript

class viewModel {
	constructor(){
  	this.data = ko.observableArray([{firstName: "phil"}, {firstName: "person"}]);
    this.selectedPerson = ko.observable("none selected");
    this.selectUser = (data) => {
    	console.log(this);
  		this.selectedPerson(data.firstName);
    }
  }
  //selectUser(data){
  //	console.log(this);
  //	this.selectedPerson(data.firstName);
  //}
}

var vm = new viewModel();

ko.applyBindings(vm);