Vue

by joplomacedo

HTML

<div id="app">
    {{a.b}}
    
    <button @click="addPropB">addPropB</button>
</div>

CSS

body {
  background: #20262E;
  padding: 20px;
  font-family: Helvetica;
}

#app {
  background: #fff;
  border-radius: 4px;
  padding: 20px;
  transition: all 0.2s;
}

li {
  margin: 8px 0;
}

h2 {
  font-weight: bold;
  margin-bottom: 15px;
}

del {
  color: rgba(0, 0, 0, 0.3);
}

Vue

new Vue({
  el: "#app",
  data: {
    a: {}
  },
	methods: {
  	addPropB() {
//    	this.$set(this.a, 'b', 5);
      this.a.b = 5;
    }
  }
})