<!DOCTYPE html>
<html>
<body>
<div id="root"></div>
</body>
<script src="https://unpkg.com/react@17.0.2/umd/react.production.min.js"></script>
<script src="https://unpkg.com/react-dom@17.0.2/umd/react-dom.production.min.js"></script>
<script src="https://unpkg.com/@babel/standalone/babel.min.js"></script>
<script type="text/babel">
function MinutesToHours() {
const [amount, setAmount] = React.useState(0);
const [inverted, setInverted] = React.useState(false);
const onChange = () => {
setAmount(event.target.value);
};
const reset = () => setAmount(0);
const onInvert = () => {
reset();
setInverted((current)=>!current); // true <-> false
}
return (
<div>
<div>
<label htmlfor="minutes">Minutes</label>
<input
value={inverted ? amount*60 : amount}
id="minutes"
placeholder= "Minutes"
type="number"
onChange={onChange}
disabled = {inverted} // === {inverted = true}
/>
</div>
<div>
<label htmlfor="hours">Hours</label>
<input
value={inverted ? amount : Math.round(amount/60)}
id="hours"
placeholder= "Hours"
type="number"
disabled = {!inverted} // === {inverted = false}
onChange={onChange}
/>
</div>
<button onClick={reset}>Reset</button>
<button onClick={onInvert}>{inverted ? "Turn back" : "Invert"}</button>
</div>
);
}
function KmToMiles(){
const [amount, setAmount] = React.useState(0);
const [inverted, setInverted] = React.useState(false);
const onChange = () => {
setAmount(event.target.value);
};
const reset = () => setAmount(0);
const onInvert = () => {
reset();
setInverted((current)=>!current); // true <-> false
}
return (
<div>
<div>
<label htmlfor="kilometer">Kilometer</label>
<input
value={inverted ? amount*1.60934 : amount}
id="kilometer"
placeholder= "Kilometer"
type="number"
onChange={onChange}
disabled = {inverted} // === {inverted = true}
/>
</div>
<div>
<label htmlfor="mile">Mile</label>
<input
value={inverted ? amount : amount/1.60934}
id="mile"
placeholder= "Mile"
type="number"
disabled = {!inverted} // === {inverted = false}
onChange={onChange}
/>
</div>
<button onClick={reset}>Reset</button>
<button onClick={onInvert}>{inverted ? "Turn back" : "Invert"}</button>
</div>
);
}
function App() {
const [index, setIndex] = React.useState("xx")
const onSelect = (event) => {
setIndex(event.target.value); //Minutes & Hours:0,KM & Miles:1
}
return (
<div>
<h1>Super Converter</h1>
<select value={index} onChange={onSelect}>
<option value="xx">Select your units</option>
<option value="0">Minutes & Hours</option>
<option value="1">KM & Miles</option>
</select>
<hr />
{index === "0" ? <MinutesToHours /> : null}
{index === "1" ? <KmToMiles /> : null}
</div>
);
}
const root = document.getElementById("root");
ReactDOM.render(<App />, root);
</script>
</html>
