Callback Function With Parameters ReactJS

Working with ReactJS and having trouble understanding how callback functions work with ReactJS.

I have a parent component titled TodoFormComponent, which initializes my list of todo items. I've created a callback function on the TodoItemsComonent, but it doesn't trigger the updateItem method and display the selected item.

Question: How can I pass data from the child to the parent? I want to pass the selected todo item to the parent so that I can update the master todo list.

Parent Component (TodoFormComponent)

The TodoFormComponent has selectedTask, which should be triggering the updateItem method.

import * as React from "react";
import TodoItemsComponent from "../todo-items/todo-items.component";
import AddTodoItemComponent from "../add-todo-item/add-todo-item.component";

export default class TodoFormComponent extends React.Component {
    constructor(){
        super();
        this.state = {
            todoItems: [
                { id: '1', todo: 'First Todo Item' },
                { id: '2', todo: 'Second Todo Item' },
                { id: '3', todo: 'Third Todo Item' }
            ],
            selected: {}
        };

        this.updateItem = this.updateItem.bind(this);
    }

    updateItem () {
        console.log('Selected Value:: ', this.state.selected);
    }

    render() {
        return (
            <div className="row">
                <div className="container">
                    <div className="well col-xs-6 col-xs-offset-3">
                        <h1>To do: </h1>
                        <div name="todo-items">
                            <TodoItemsComponent items={this.state.todoItems} selectedTask={() => {this.updateItem}}/>
                        </div>
                        <div name="add-todo-item">
                            <AddTodoItemComponent/>
                        </div>
                    </div>
                </div>
            </div>
        )
    }
}

Child Component (TodoItemsComponent)

The TodoItemsComponent has an onClick to update the selected value. This gets updated in the selectedTask function. import * as React from "react";

export default class TodoItemsComponent extends React.Component {
    constructor(props) {
        super(props);
    }

    selectedTask (item) {
        this.setState({selected: item})
    }

    render() {
        return (
            <ul className="list-group">
                {
                    this.props.items.map((item) => {
                        return (
                            <li className="list-group-item">
                                {item.todo}
                                <div className="pull-right">
                                    <button
                                        type="button"
                                        className="btn btn-xs btn-success">
                                        &#x2713;
                                    </button> <button
                                        type="button"
                                        className="btn btn-xs btn-danger"
                                        onClick={() => {this.selectedTask(item)}}
                                        >&#xff38;
                                    </button>
                                </div>
                            </li>
                        )
                    })
                }
            </ul>
        )
    }
}