EDIT 2
- For all object changes that need reactivity use
Vue.set(object, prop, value)
- For array mutations, you can look at the currently supported list here
EDIT 1
For vuex you will want to do Vue.set(state.object, key, value)
Original
So just for others who come to this question. It appears at some point in Vue 2.* they removed this.items.$set(index, val)
in favor of this.$set(this.items, index, val)
.
Splice is still available and here is a link to array mutation methods available in vue link.