Question

How can I pass arguments to a getter inside mapGetters? Is this on the right way to react a state change on widgetFetched.posts and posts at the same time? In other words, can my getter react to these changes?

Explanation

I'm trying to make my Component react to a change in State in my Vuex Store through a getter. To achieve this, I'm using mapGetters inside my Component. But this getter receives an argument, an id to filter my state (that is flatten).

I have two states (that are dictionaries): widgetsFetched and posts. One widgetFetched has a property called posts that is an array of Post.Id. And the state posts is a dictionary whose keys are Post.Id.

So, I have a getter called getPostsByWidgetId that takes one argument widgetId. Then, my getter returns an array containing posts filtered by widgetFetched.posts's ids.

Store

const store = new Vuex.Store({
  state: {
    widgetsFetched: {
        1: { id: 1, done: true, posts: [1, 2, 3, 4] },
        2: { id: 2, done: false, posts: [5, 6] }
    },
    posts: {
        1: { name: '...', id: 1, content: '...' },
        2: { name: '...', id: 2, content: '...' },
        3: { name: '...', id: 3, content: '...' },
        4: { name: '...', id: 4, content: '...' },
        5: { name: '...', id: 5, content: '...' },
        6: { name: '...', id: 6, content: '...' }
    }
  },
  getters: {
    getPostsByWidgetId: (state, getters) => (widgetId) => {
      if (widgetId && state.widgetsFetched[widgetId] && state.widgetsFetched[widgetId].posts) {
        return state.widgetsFetched[widgetId].posts.map((postId) => {
          return state.posts[postId]
        })
      }
    }
  }
})

Component

My components looks like:

<template>
  <div>
    <p v-for="post in posts(this.widget._id)" >{{ post.id }} - {{ post.score }}</p>
  </div>
</template>

<script>
  import { mapGetters } from 'vuex'

  export default {
    name: 'reddit',
    props: ['widget'],
    computed: {
      ...mapGetters({
        posts: 'getPostsByWidgetId'
      })
    }
  }
</script>

<style scoped>
</style>

Examples