我的Vuex商店有一组数据,比如1000条记录。有一个带参数getter的getter,获取一个ID并返回正确的记录。
我需要访问该getter的组件知道数据何时就绪(当完成所有记录的异步提取时)。
然而,由于它是一个参数化的getter,Vue并没有观察它所依赖的状态,知道何时更新它。我该怎么办?
我一直想恢复到我在Angular中使用的BehaviorSubject模式,但是Vuex + rxJS看起来很重,对吧?
我觉得我需要以某种方式为getter重新计算一个触发器。
store.js
import Vue from 'vue'
import Vuex from 'vuex'
import VueResource from 'vue-resource'
Vue.use(VueResource);
Vue.use(Vuex)
export default new Vuex.Store({
state: {
numberOfPosts : -1,
posts : {}, //dictionary keyed on slug
postsLoaded : false,
},
getters : {
postsLoaded : function(state){
return state.postsLoaded;
},
totalPosts : function(state){
return state.numberOfPosts;
},
post: function( state ){
return function(slug){
if( state.posts.hasOwnProperty( slug ) ){
return state.posts.slug;
}else{
return null;
}
}
}
},
mutations: {
storePosts : function(state, payload){
state.numberOfPosts = payload.length;
for( var post of payload ){
state.posts[ post.slug ] = post;
}
state.postsLoaded = true;
}
},
actions: {
fetchPosts(context) {
return new Promise((resolve) => {
Vue.http.get(' {url redacted} ').then((response) => {
context.commit('storePosts', response.body);
resolve();
});
});
}
}
})
Post.vue
<template>
<div class="post">
<h1>This is a post page for {{ $route.params.slug }}</h1>
<div v-if="!postsLoaded">LOADING</div>
<div v-if="postNotFound">No matching post was found.</div>
<div v-if="postsLoaded && !postNotFound" class="post-area">
{{ this.postData.title.rendered }}
</div>
</div>
</template>
<script>
import { mapGetters } from 'vuex'
export default {
name: 'post',
data : function(){
return {
loading : true,
postNotFound : false,
postData : null
}
},
mounted : function(){
this.postData = this.post( this.$route.params.slug );
if ( this.postData == null ){
this.postNotFound = true;
}
},
computed : mapGetters([
'postsLoaded',
'post'
])
}
</script>
就目前而言,它显示“post not found”消息,因为当它访问getter时,数据还没有准备好。如果找不到帖子,我需要区分(a)数据已加载且没有匹配的帖子,以及(b)数据未加载等等