Vuex mapMutations

VueX mapMutations: is used simply to replace this.$store.commit('abc') to  mapMutations(['abc','..']). its functionalities are the same but mapMutations is more preferable and useful as it is able to combine different functions in mutations into one.

Example:

App.vue
<template>
<div id="app">
<Counter />
</div>
</template>

<script>
import {store, Counter } from './state/simple'

export default {
name: 'app',
store,
components: {
Counter
},
data () {
return {
placeHolder: 'Focus on me'
}
},

}
</script>

simple.js
import Vue from 'vue';
import Vuex, { mapGetters, mapMutations } from 'vuex';
Vue.use(Vuex)


const store = new Vuex.Store({
state: {
products:[
{id:1,name:'pizza', price:10},
{id:2, name:'fan', price: 20},
{id:3, name:'headset', price:30 },
{id:4,name: 'phone', price: 1004}
]
},
mutations: {
deductPrice( state ) {
return state.products.map(item => item.price -= 1)
}
},
getters:{
getBigPrice (state) {
return state.products.filter(item => item.price >= 10)
},
getCountItem ( state, getters ) {
return getters.getBigPrice.length
}
},
actions:{
}
})

const Counter = {
template: `<div> Total {{ itemCount }}
<li v-for="product in products"> Id:{{ product.id }},
name:{{ product.name }}, Price:{{ product.price }} </li><br/>
<button @click="deductPrice">Deduct</button>
</div>`,
computed:{
...mapGetters(
{ products: 'getBigPrice',
itemCount: 'getCountItem'}
)
},
methods:{
...mapMutations(['deductPrice'])
}
}
export {store, Counter }

mapMutation calls deductPrice handler function in mutations properties like
methods:{
...mapMutations(['deductPrice'])
}

One more note here is that we could not call mapMutations with payload injected. 

 To overcome the issues raised above, we can do like this:
mutations: {
deductPrice( state ) {
return state.products.map(item => item.price -= 1)
}
}

Note: mutations handler function must be synchronous otherwise, it is impossible to track those functions inside mutation logs.

Final result:


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