vuejs - template, store, this.$store is undefined - vue.js

I have a problem retreiving the vuex store in a vuejs component.
My architecture is pretty straight-forward. I have a store with two modules.
main.js
new Vue({
el: '#app',
store,
router,
template: '<App/>',
components: {
App
},
Events.vue - Here I use my custom component UserDropdown in a syncfusion component, but I dont think that's relevant. The first registers the UserDropdown, the second fragment will be called when you click on a cell and returns my custom component:
...
components: {
UserDropdown
},
...
editTemplate: function () {
return {template: UserDropdown}
},
...
UserDropdown.vue - here I'd like to use the store, but the result is: "this.$store is undefined". Access to the store from within other components like Events.vue works just fine.
computed: {
users: function () {
return this.$store.state.usersState.users;
}
store.js
import Vue from 'vue';
import Vuex from 'vuex';
import projectsState from './modules/projectsStore'
import usersState from './modules/usersStore'
import createLogger from 'vuex/dist/logger'
Vue.use(Vuex);
const debug = process.env.NODE_ENV !== 'production';
export const store = new Vuex.Store({
modules: {
projectsState,
usersState
},
strict: debug,
plugins: debug ? [createLogger()] : []
});
Why doesnt that work? Is the problem related to the "template: UserDropdown"? I thought every component should be able to access the store...

As it looks, one has to import the store once again in the UserDropdown.vue component. That doesn't make any sense to me, since I imported the store in the new Vue instance as shown above.
Here the code fragments to be added in the UserDropdown.vue
...
import {store} from "../store/store";
...
export default {
store,
name: 'UserDropdown',
...
...mapGetters({users: 'usersState/AllUsers'})
...

Related

How to use vuex action in function

I'm new to Vue, so it's likely I misunderstand something. I want to call a vuex action inside a local function in App.vue like so:
<template>
<div id="app">
<button #click="runFunction(1)">Test</button>
</div>
</template>
<script>
import { mapActions } from 'vuex'
export default{
data() { return { } },
methods: {
...mapActions(['doAction']),
buttonClicked: (input) => { runFunction(input) }
}
}
function runFunction(input){
doAction({ ID: input });
}
</script>
The action calls a mutation in store.js
import Vue from 'vue'
import Vuex from 'vuex'
Vue.use(Vuex);
export default new Vuex.Store({
state: {
IDs: []
},
mutations: {
doAction: (state, id) => { state.IDs.push(id) }
},
actions: {
doAction: ({ commit }, id) => { commit('doAction', id) }
}
})
I also have a main.js that sets up the vue:
import Vue from 'vue'
import App from './App.vue'
import store from './store'
new Vue({
el: '#app',
store,
render: h => h(App)
})
The error I'm getting is:
ReferenceError: doAction is not defined
at runFunction
How can I call the mapped action inside a function? Version is Vue 2.6.10
There are several problems with defining runFunction as a 'local function':
function runFunction(input){
doAction({ ID: input });
}
Firstly, this is just a normal JavaScript function and the usual scoping rules apply. doAction would need to be defined somewhere that this function can see it. There is no magic link between this function and the component defined in App.vue. The function will be accessible to code in the component, such as in buttonClicked, but not the other way around.
The next problem is that it won't be available within your template. When you write runTemplate(1) in your template that's going to be looking for this.runTemplate(1), trying to resolve it on the current instance. Your function isn't on the current instance. Given your template includes #click="runFunction(1)" I'm a little surprised you aren't seeing a console error warning that the click handler is undefined.
mapActions accesses the store by using the reference held in this.$store. That reference is created when you add the store to your new Vue({store}). The store may appear to be available by magic but it's really just this.$store, where this is the current component.
It isn't really clear why you're trying to write this function outside of the component. The simplest solution is to add it to the methods. It'll then be available to the template and you can access doAction as this.doAction.
To keep it as a separate function you'd need to give it some sort of access to the store. Without knowing why you want it to be separate in the first place it's unclear how best to achieve that.
Of course it is not defined outside your instance .... you have to import the exported store from store.js on your function component :
<script>
import { mapActions } from 'vuex'
import store from 'store.js'
export default{
data() { return { } },
methods: {
...mapActions(['doAction']),
buttonClicked: (input) => { runFunction(input) }
}
}
function runFunction(input){
store.commit({ ID: input });
}
</script>

Call vuex store without mapState

So I'm experimenting with a new project created with vue cli, where I am using router and VueX
So in my HelloWorld.vue file, I've got this code in the script section:
import { mapState } from 'vuex'
export default {
name: 'hello',
computed: mapState({
msg: 'nombre'
}),
Is there a more direct way of calling values in the state?, like for example I would like to do
msg: store.nombre
My vuex store is defined in the root main.js like this:
//vuex
import Vuex from 'vuex'
Vue.use(Vuex)
const store = new Vuex.Store({
state: {
nombre: "POS vuex"
}
});
new Vue({
el: '#app',
router,
store,
template: '<App/>',
components: { App }
})
Actually I was looking for this way:
msg: this.$store.state.nombre
(I was missing the ".state." part)
As soon as you're using mapState as computed you can actually call these states with this in that component - in the template or script section:
Use the ... operator on your mapState and you're done:
Example:
Your store:
const store = new Vuex.Store({
state: {
nombre: "POS vuex",
otherState: "abc",
anotherState: "efg"
}
});
Your component:
<template>
<div id="test">
{{ nombre }}
{{ otherState }}
</div>
</template>
<script>
import { mapState } from 'vuex'
export default {
name: 'hello',
methods: {
logState() {
console.log(this.anotherState);
}
},
computed: {
...mapState(["nombre", "otherState", "anotherState"]),
}
}
</script>
In addition to the the mapState helper
computed: {
...mapState('moduleOne', ['keyOne', 'keyTwo'])
}
which lets you access the values via this.keyOne and this.keyTwo inside your component.
You can also add your store to the root vue instance and access your state inside your components via the global this.$store directive.
this.$store.module.keyOne
this.$store.module.keyTwo
Additionally if you need to access your store from outside your components you can also export the store and import it directly from non-component code.
If you export your store:
import Vue from 'vue'
import Vuex from 'vuex'
import moduleTwo from './modules/moduleOne'
import moduleOne from './modules/moduleTwo'
Vue.use(Vuex)
const store = new Vuex.Store({
strict: true,
modules: {
moduleOne,
moduleTwo
}
})
export default store
You can import it anywhere you need to access state, getters, actions, and mutations.
import store from '#/store'
console.log(store.state.moduleOne.keyone)
store.dispatch('moduleOne/actionOne', { keyOne: valOne })
store.getters['moduleOne/getterOne']
store.commit('moduleOne/mutationOne', data)
Call you'r state in created method of vuex.
THanks

Vuejs and Webpack: Why is store undefined in child components

I am using Vuejs with Webpack.
Here's store.js:
import Vuex from "vuex";
export default new Vuex.Store({
state: {
count : 0
},
mutations: {
increment (state) {
state.count++
}
}
});
Here is my app.js:
"use strict";
import Vue from 'vue';
window.Vue = Vue;
import MyComponent from './MyComponent.vue';
import store from './store.js';
window.App = new Vue({
el : '#my-app',
store,
components : {
'my-component' : MyComponent
}
});
Here is the script from MyComponent.vue:
export default {
computed : {
count() {
return this.$store.state.count;
}
},
mounted() {
console.log(this.$store)
}
}
Any reference to this.$store in my component is undefined. Why?
You need to install the Vuex plugin somewhere to allow Vue components to access the store. As Pavan noted, to do this you must include the following lines somewhere (in your app's index.js, in your store.js etc) before you create your Vue instance:
import Vue from "vue";
import Vuex from "vuex";
Vue.use(Vuex);
This tells Vue what to do with the store instance when you create the instance, which will make it available under this.$store in your components. This also ensures that Vuex also knows how to interact with Vue. Without it, you will not be able to use Vue and Vuex together properly.
Regarding your later answer, you can export the store instance just fine, and import it into your index.js, router config etc. For example:
store.js:
import Vuex from "Vuex";
export default new Vuex.Store({ /* store config */ });
MyComponent.vue's <script> block:
export default {
mounted() {
console.log(this.$store); // will log the store instance
}
}
index.js:
import Vue from "vue";
import Vuex from "vuex";
import store from "./store";
import MyComponent from "./components/MyComponent.vue";
Vue.use(Vuex);
const app = new Vue({
el: "#my-app"
store,
components: { MyComponent },
// any other options as needed
});
You should add these 2 lines in your store.js
import Vue from "vue";
Vue.use(Vuex);
There's no way you can instantiate store without actually saying the second statement above. So, you need to import Vue in your store.js
OK, so the reason I wanted to go down this path was to separate the store code from the rest of the application.
I have managed to do that by exporting a default object from store.js, where that object is only the configuration for the store (i.e. not a store instance). I then instantiate the store in my app.js, using the imported configuration.
I will leave this answer open for a few days in case someone wants to provide a way to export/import the instance itself.

I can't access to Vuex data: using vue-cli webpack

Right now, I'm trying to show the contents of state object from store.js on my App.vue.
I've tried vuex examples on Medium and other website, but I'm keep failing: non of them worked: some of them even gave me a WebPack config error.
My App.vue
<template>
<div id="app">
<img src="./assets/logo.png">
<h1>TEST</h1>
</div>
</template>
<script>
import Store from './store/index'
export default {
name: 'App',
Store
}
</script>
My store/index.js
import Vue from 'vue'
import Vuex from 'vuex'
Vue.use(Vuex)
export default new Vuex.Store({
state: {
alpha: ['1st data']
},
mutations: {
ADD ({ alpha }) {
const beta = 'new!'
state.alpha.push(beta)
}
}
})
My main.js
import Vue from 'vue'
import App from './App'
import Vuex from 'vuex'
import store from './store/index'
Vue.config.productionTip = false
/* eslint-disable no-new */
new Vue({
el: '#app',
store,
components: { App },
template: '<App/>'
})
You shouldn't be importing the store in App.vue. It only needs to be included in main.js and passed as an option when constructing the Vue instance. Within a component, the store is thereafter accessible via this.$store.
Second, your mutation should receive a context object as it's first parameter. context consists of properties such including state and commit. Those are the ways in which you access state within a mutation.
// notice context is the first parameter
mutations: {
ADD (context, { param }) {
const beta = 'new!'
context.state.alpha.push(beta)
})
}
// you can also deconstruct context like this
mutations: {
ADD ({state}, { param }) {
const beta = 'new!'
state.alpha.push(beta)
})
}
I also changed the way alpha to param. You don't receive the state's properties unless you destructure even further.
The problem is that in your main.js is missing Vue.use(veux)
you should have something like this:
import Vue from 'vue'
import Vuex from 'vuex'
import App from './App'
import store from './store'
Vue.use(Vuex) // <-- Add this
/* eslint-disable no-new */
new Vue({
el: '#app',
store,
template: '<App/>',
components: { App }
})

Vuex data store not found in components

I'm using a project with Vue, Vuetify, Vue-Router, and Vuex. The intent was to create a basic layout with a sidebar in a more module approach to dabble in scalability with Vue. So I created a folder called Store, which has a modules folder. So my index file within the store folder is as follows:
import Vue from 'vue';
import Vuex from 'vuex';
import global from './Modules/Global';
Vue.use(Vuex);
export default new Vuex.Store({
modules: {
site: global
}
});
The module is broken down into a single file with actions, getters, mutations, and state.
const actions = {
sidebarState: ({ commit }, status) => {
commit('openOrCloseSidebar', status);
}
}
const mutations = {
openOrCloseMenu: (status) => {
if (status !== true)
return state.sidebar = true;
return state.sidebar = false;
}
};
const getters = {
};
const state = {
sidebar: true
};
export default {
namespaced: true,
actions,
mutations,
getters,
state
};
I invoke the Vue instance as follows.
import Vue from 'vue/dist/vue';
import Vuetify from 'vuetify';
import Axios from 'axios';
import application from './Template/Application.vue';
import router from './Router';
import store from './Store';
import { sync } from 'vuex-router-sync';
Vue.use(Vuetify);
Vue.use(router);
Vue.use(store);
sync(store, router);
var vue = new Vue({
el: '#application',
template: '<application></application>',
components: {
application
},
router: router,
store: store
});
However, when I call this.$store.global.state.sidebar or this.$store.state.sidebar Vue is unable to find my property. I receive the error:
Cannot read property global of undefined.
The error also references state, but I believe since I'm using namespace the syntax should mirror above. Where I attempt to call that is here.
<template>
<v-container>
<application_sidebar :my-prop="menu"></application_sidebar>
<application_navigation :my-prop="menu"></application_navigation>
</v-container>
</template>
<script type="text/javascript">
import application_navigation from './Navigation.vue'
import application_sidebar from './Sidebar.vue';
import { mapState } from 'vuex';
export default ({
components: {
application_navigation,
application_sidebar
},
data: {
menu: this.$store.global.state.sidebar
}
});
</script>
I'm trying to access my state and learn how to correctly emit, so in the navigation component I can emit upward so the value is reflected to move the sidebar open or close.
Any help would be terrific, I'm quite new to Vue.
I think the main problem is your path to your module state is meant to be this.$store.state.site.
The recommended method is to use computed properties. For example
computed: {
menu() {
return this.$store.state.site.sidebar
}
}
You can also use the mapState helper
import { mapState } from 'vuex'
export default {
computed: mapState({ menu: state => state.site.sidebar })
}
The this variable does not reference the Vue instance when you are trying to access the store via this.$store.
The data object needs to be a method that returns an object.
data() {
return { menu: this.$store.state.site.sidebar };
}
However, by retrieving the value from the store's state object the data method like this, you are only setting the value of the menu data property when the Vue instance initializes. The value of menu will not update in response to changes to the value in the store's state.
If you need the menu value to be reflective of the state object throughout the life of the Vue instance, then you'd need to use a computed property or mapState, as suggested in #Phil's answer.