React: Lifting state up example, with TypeScript

LiftingState.tsx

import { useState } from 'react'

/*
"Lifting state up" is useful when several components need to share state.
In this example, both Parent and Child needs to display the value of
"clicks". Child needs to update the value as well. We are lifting the
state up, out of the child component, into its parent.

1. Move the shared state to the common component - the component that
contains all of the components that needs to share state. Here, Parent is
the common component, because it contains Child.

2. Pass the current value to each component that needs it, using props.

3. Create functions that modify the state in the common component. Pass
those functions to each component that needs to modify the state.
*/

const Parent = () => {
	const [clicks, setClicks] = useState<number>(0)
	const whenClick = () => setClicks(clicks + 1)
	
	return (
		<div>
			<p> Clicks: {clicks} </p>
			<Child clicks={clicks} whenClick={whenClick} />
		</div>
	)
}

interface ChildProps {
	clicks: number;
	whenClick: () => void;
}
		
const Child = ({ clicks, whenClick }: ChildProps) => (
	<p>
		You have clicked me {clicks} times. <br />
		<button onClick={whenClick}> Do it </button>
	</p>
)

export default Parent