<template>
  <h2>Example expose Option</h2>
  <p>The 'expose' option is not used, so all child properties are available to the parent by default, both the 'message' data property, and the 'createAlert()' method:</p>
  <button v-on:click="{ this.$refs.childComp.message += 'Hello! '; }">Write 'Hello!'</button>
  <button v-on:click="{ this.$refs.childComp.createAlert(); }">Create alert</button>
  <child-comp ref="childComp"/>
</template>                  

<template>
  <div>
    <h3>ChildComp.vue</h3>
    <p>Message from parent component:</p>
    <p id="pEl">{{ message }}</p>
  </div>
</template>

<script>
export default {
  data() {
    return {
      message: ' '
    }
  },
  methods: {
    createAlert() {
      alert('This is an alert, from the child component')
    }
  }
}
</script>

<style scoped>
div {
  border: solid black 1px;
  padding: 10px;
  max-width: 350px;
  margin-top: 20px;
}
#pEl {
  background-color: lightgreen;
  font-family: 'Courier New', Courier, monospace;
}
</style>                  

import { createApp } from 'vue'

import App from './App.vue'
import ChildComp from './components/ChildComp.vue'

const app = createApp(App)
app.component('child-comp', ChildComp)
app.mount('#app')