vuex 状态更改后，Vue 组件不会重新渲染

Question

My vue component doesn´t change a child component when the state of vuex changes.

I have a list of slots for items and want to render items depending on a vuex state variable.

When you click on a "item"-component it sets the selectedItem state variable. Another component watches this variable and sets equippedItems variable with new data.

But when I try to change an item it doesn't show up, even though the state seems to change in Vuex.

I have set up the vuex store like that:

const state = {
    equippedItems:
        [
            {
                name: 'Item 1',
                strength: 3,
                itemType: 1,
                rarity: 3
            },
            {
                name: 'Item 2',
                strength: 40,
                itemType: 2,
                rarity: 2
            }
        ],
    selectedItem: null
}

const getters = {

    getEquippedItems: (state) => state.equippedItems,


    getSelectedItem: (state) => state.selectedItem
}

const mutations = {

    changeSelectedItem: (state, newItem) => {
        state.selectedItem = newItem;
    },

    changeEquippedItems: (state, parameters) => {
        state.equippedItems[parameters[0]] = parameters[1];
    }
}

const actions = {
    setSelectedItem({ commit }, index) {
        commit('changeSelectedItem', index);
    },

    setNewEquipment({ commit }, parameters) {
        commit('changeEquippedItems', parameters);
    }
}

export default {
    state,
    getters,
    actions,
    mutations
}

Then I have a component that sets the items according to the equippedItems variable

import { mapGetters, mapActions } from 'vuex';
import Item from '../Item';

export default {
    name: 'equipped-items',
    components: {
        Item
    },
    props: [],
    data() {
        return {
            chooseHead: false,
        }
    },
    computed: {
        ...mapGetters(['getEquippedItems', 'getItems', 'getSelectedItem'])

    },
    methods: {
        ...mapActions(['setNewEquipment']),
        chooseNewHead() {
            this.chooseHead = !this.chooseHead;
        }
    },
    watch: {
        getSelectedItem: function () {
            if (this.chooseHead) {
                this.setNewEquipment([0, this.getSelectedItem]);
            }
        }
    }
}

<section class="equipped-items">

    <div @click="chooseNewHead" class="head equipSlot">
        <Item v-if="getEquippedItems[0]" :passedItem="getEquippedItems[0]" :parent="'equip'"> </Item>
    </div>

    <div class="body equipSlot">
        <Item v-if="getEquippedItems[1]" :passedItem="getEquippedItems[1]"></Item>
    </div>
</section>

Then there is the item component which sets the vuex variable selectedItem on click.

import { mapActions } from 'vuex';

export default {
    name: 'Item',
    props: ['passedItem', 'parent'],
    methods: {
        ...mapActions(['setSelectedItem']),
        selectedItem() {
            if (this.parent != 'equip') {
                this.setSelectedItem(this.passedItem);
            }
        }
    }
}

It renders fine the first time when the page is loading, but doesn't change the new passed item to the item-component.

Thanks in advance

Answer 1

There a couple mistakes in your code:

1- I couldn't identify where you call/trigger an event to your selectedItem() method in your component.

2-(This is an extra) If you want to append objects to an array injavascript you just use array.push(odject) , so i would suggest you to change your changeEquippedItems mutation to:

changeEquippedItems: (state, parameters) => {
        state.equippedItems.push(parameters);
    }