<template>
  <h2>Example $watch() Method</h2>
  <p>The watcher is set up to watch 'value.country' and will therefore detect when the country is changed inside the 'value' object.</p>
  <div>
    <p>Register a new country for Stuart to live in:</p>
    <p><input type="text" v-model="inpVal"></p>
    <button v-on:click="regHobby">Register</button>
    <ol>
      <li v-for="x in watchMessages">{{ x }}</li>
    </ol>
  </div>
  <p>Current 'value' object:</p>
  <pre>{{ this.value }}</pre>
</template>

<script>
export default {
  data() {
    return {
      inpVal: null,
      value: {
        owner: 'Stuart',
        address: 'Faraway Lane',
        country: 'Mexico'
      },
      watchMessages: []
    };
  },
  methods: {
    regHobby() {
      this.value.country = this.inpVal;
      this.inpVal = null;
    }
  },
  mounted() {
    this.$watch('value.country', function () {
      this.watchMessages.push('watcher triggered')
    });
  }
};
</script>

<style scoped>
div {
  border: solid black 1px;
  padding: 10px;
}
li {
  background-color: lightgreen;
}
</style>                  

import { createApp } from 'vue'

import App from './App.vue'

const app = createApp(App)
app.mount('#app')