Well, this question came after this question of mine. How to disable button if multiple form inputs do not change in Vue.js

There is Switch at every form. When a form inputs are changed, the switch needs to be ON from the OFF state. I have done it by putting this line into the watch method on each form

this.items.forEach( (_, index) => {
  this.$watch(['items', index].join('.'), {deep: true, handler: (newVal, oldVal) => {
      this.changed.push(newVal.id)
      this.items[index].switch = true
     }});
  });

After adding this line, this.items[index].switch = true, the Switch is getting ON from OFF; but if a user then OFF the Switch again by clicking on the Switch; the text is not changing anymore. It's always remaining ON. how to fix that?

CodePen Demo