<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8">
<title></title>
<script src="vue.js" type="text/javascript" charset="utf-8"></script>
</head>
<body>
<div id="root">
<template v-if="loginType === 'username'">
<label>Username</label>
<input placeholder="Enter your username" key="username-input">
</template>
<template v-else>
<label>Email</label>
<input placeholder="Enter your email address" key="email-input">
</template>
<button @click="toggleLoginType">Toggle login type</button>
</div>
<script src="https://cdn.jsdelivr.net/npm/vue/dist/vue.js"></script>
<script type="text/javascript">
var vm = new Vue({
el: '#root',
data: {
loginType: 'username'
},
methods: {
toggleLoginType: function() {
return this.loginType = this.loginType === 'username' ? 'email' : 'username'
}
}
});
</script>
</style>
</body>
</html>