Vue

by joplomacedo

HTML

<div id="app">
  <p>{{watchedCount}}</p>
  <button @click="handleClick">Click me</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: {
	  watchedCount:0,
		arr: [
    	[1,2]
    ]
  },
  watch: {
	  arr(arr) {
	    console.log(arr);
			this.watchedCount++;
    }
  },
  methods: {
  	handleClick(){
    	this.arr[0][0] = (this.arr[0][0] + 1)
      this.arr = [...this.arr];
    }
  }
})