I have a composable file in my VueJS application:
// simple example of a composable that fetch some information from API and shows that information
// in a table in two components at the sime time
export function useDatatable () {
const table = ref({
headers: [...],
items: [],
someValue: ''
})
async function getDocuments () {
const { data } = await $axios.get('/documents')
table.value.items = data
}
return {
table,
getDocuments
}
}
Then I have multiple components that use this composable at the same time:
<template>
<div>
<document-table /> // composable is used here
<document-billing-dialog /> // composable is used here too
</div>
</template>
Then in both components (document-table and document-billing-dialog) I use this composable like this:
<template>
<div>
{{ table.someValue }}
</div>
<v-table :items="table.items" />
<v-btn #click="getDocuments">
Reload table
</v-btn>
// other components
</template>
<script>
import { useDatatable } from '~/composables/useDatatable'
// other imports
export default defineComponent({
setup () {
const { table, getDocuments } = useDatatable()
onMounted(() => { getDocuments() })
return {
table,
getDocuments
}
}
})
</script>
However when 1 component calls the getDocuments function it gets called twice because its being used in two components at the same time.
Other example is that if I change the value of table.value.someValue = 'something' it changes in both components.
Is there any way to have multiple instances of a composable at the same time without sharing the state?
Related
I have an Array of posts inside reactive() and I want it to be updated onMounted.
How can I do this?
TEMPLATE:
<q-card>
<board-item-list :items="items" v-if="items.length" />
<board-empty v-else />
</q-card>
SCRIPT
import { reactive, onMounted } from "vue";
import { posts } from "./fake-data.js";
export default {
setup() {
let items = reactive([]);
...
onMounted(() => {
// to fill the items with posts.
items.values = posts; // I tried this not working
items = posts; //I tried this not working
console.log(items);
});
...
return {
...
items,
};
},
};
Try to use ref instead of reactive or define items as nested field in a reactive state like :
import { reactive, onMounted } from "vue";
import { posts } from "./fake-data.js";
export default {
setup() {
let state= reactive({items:[]});
...
onMounted(() => {
state.items = posts;
console.log(state.items);
});
...
return {
...
state,
};
},
};
in template :
<q-card>
<board-item-list :items="state.items" v-if="state.items.length" />
<board-empty v-else />
</q-card>
if you want to get rid of state in the template you could use toRefs:
import { reactive, onMounted,toRefs } from "vue";
import { posts } from "./fake-data.js";
export default {
setup() {
let state= reactive({items:[]});
...
onMounted(() => {
state.items = posts;
console.log(state.items);
});
...
return {
...toRefs(state),//you should keep the 3 dots
};
},
};
composition api is very frustrating, vue2 was much better.
composition api is much more complex with basically no tangible benefit
composition api has so many reactivity problems like the above, proxy objects, pointless wrapper, total waste of space imho, vue3 is a great example of developers wrecking a good project.
I am using the composition api plugin for vue2 (https://github.com/vuejs/composition-api) to reuse composables in my app.
I have two components that reuse my modalTrigger.js composable, where I'd like to declare some sort of shared state (instead of using a bloated vuex state management).
So in my components I do something like:
import modalTrigger from '../../../../composables/modalTrigger';
export default {
name: 'SearchButton',
setup(props, context) {
const { getModalOpenState, setModalOpenState } = modalTrigger();
return {
getModalOpenState,
setModalOpenState,
};
},
};
And in my modalTrigger I have code like:
import { computed, ref, onMounted } from '#vue/composition-api';
let modalOpen = false; // needs to be outside to be accessed from multiple components
export default function () {
modalOpen = ref(false);
const getModalOpenState = computed(() => modalOpen.value);
const setModalOpenState = (state) => {
console.log('changing state from: ', modalOpen.value, ' to: ', state);
modalOpen.value = state;
};
onMounted(() => {
console.log('init trigger');
});
return {
getModalOpenState,
setModalOpenState,
};
}
This works, but only because I declare the modalOpen variable outside of the function.
If I use this:
export default function () {
const modalOpen = ref(false); // <------
const getModalOpenState = computed(() => modalOpen.value);
...
It is not reactive because the modalTrigger is instantiated twice, both with it's own reactive property.
I don't know if that is really the way to go, it seems, that I am doing something wrong.
I also tried declaring the ref outside:
const modalOpen = ref(false);
export default function () {
const getModalOpenState = computed(() => modalOpen.value);
But this would throw an error:
Uncaught Error: [vue-composition-api] must call Vue.use(plugin) before using any function.
So what would be the correct way to achieve this?
I somehow expected Vue to be aware of the existing modalTrigger instance and handling duplicate variable creation itself...
Well, anyway, thanks a lot in advance for any hints and tipps.
Cheers
Edit:
The complete header.vue file:
<template>
<header ref="rootElement" :class="rootClasses">
<button #click="setModalOpenState(true)">SET TRUE</button>
<slot />
</header>
</template>
<script>
import { onMounted, computed } from '#vue/composition-api';
import subNavigation from '../../../../composables/subNavigation';
import mobileNavigation from '../../../../composables/mobileNavigation';
import search from '../../../../composables/searchButton';
import { stickyNavigation } from '../../../../composables/stickyNav';
import metaNavigation from '../../../../composables/metaNavigation';
import modalTrigger from '../../../../composables/modalTrigger';
export default {
name: 'Header',
setup(props, context) {
const { rootElement, rootClasses } = stickyNavigation(props, context);
mobileNavigation();
subNavigation();
search();
metaNavigation();
const { getModalOpenState, setModalOpenState } = modalTrigger();
onMounted(() => {
console.log('Header: getModalOpenState: ', getModalOpenState.value);
setModalOpenState(true);
console.log('Header: getModalOpenStat: ', getModalOpenState.value);
});
return {
rootClasses,
rootElement,
getModalOpenState,
setModalOpenState,
};
},
};
</script>
The composition API is setup somewhere else where there are Vue components mounted a bit differently than you normally would.
So I can't really share the whole code,but it has this inside:
import Vue from 'vue';
import CompositionApi from '#vue/composition-api';
Vue.use(CompositionApi)
The composition API and every other composable works just fine...
I have the following parent component which has to render a list of dynamic children components:
<template>
<div>
<div v-for="(componentName, index) in supportedComponents" :key="index">
<component v-bind:is="componentName"></component>
</div>
</div>
</template>
<script>
const Component1 = () => import("/components/Component1.vue");
const Component2 = () => import("/components/Component2.vue");
export default {
name: "parentComponent",
components: {
Component1,
Component2
},
props: {
supportedComponents: {
type: Array,
required: true
}
}
};
</script>
The supportedComponents property is a list of component names which I want to render in the parent conponent.
In order to use the children components in the parent I have to import them and register them.
But the only way to do this is to hard code the import paths of the components:
const Component1 = () => import("/components/Component1.vue");
const Component2 = () => import("/components/Component2.vue");
And then register them like this:
components: {
Component1,
Component2
}
I want to keep my parentComponent as generic as possible. This means I have to find a way to avoid hard coded components paths on import statements and registering. I want to inject into the parentComponent what children components it should import and render.
Is this possible in Vue? If yes, then how?
You can load the components inside the created lifecycle and register them according to your array property:
<template>
<div>
<div v-for="(componentName, index) in supportedComponents" :key="index">
<component :is="componentName"></component>
</div>
</div>
</template>
<script>
export default {
name: "parentComponent",
components: {},
props: {
supportedComponents: {
type: Array,
required: true
}
},
created () {
for(let c=0; c<this.supportedComponents.length; c++) {
let componentName = this.supportedComponents[c];
this.$options.components[componentName] = () => import('./' + componentName + '.vue');
}
}
};
</script>
Works pretty well
Here's a working code, just make sure you have some string inside your dynamic import otherwise you'll get "module not found"
<component :is="current" />
export default { data () {
return {
componentToDisplay: null
}
},
computed: {
current () {
if (this.componentToDisplay) {
return () => import('#/components/notices/' + this.componentToDisplay)
}
return () => import('#/components/notices/LoadingNotice.vue')
}
},
mounted () {
this.componentToDisplay = 'Notice' + this.$route.query.id + '.vue'
}
}
Resolving dynamic webpack import() at runtime
You can dynamically set the path of your import() function to load different components depending on component state.
<template>
<component :is="myComponent" />
</template>
<script>
export default {
props: {
component: String,
},
data() {
return {
myComponent: '',
};
},
computed: {
loader() {
return () => import(`../components/${this.component}`);
},
},
created() {
this.loader().then(res => {
// components can be defined as a function that returns a promise;
this.myComponent = () => this.loader();
},
},
}
</script>
Note: JavaScript is compiled by your browser right before it runs. This has nothing to do with how webpack imports are resolved.
I think we need some plugin that can have code and every time it should load automatically. This solution is working for me.
import { App, defineAsyncComponent } from 'vue'
const componentList = ['Button', 'Card']
export const registerComponents = async (app: App): void => {
// import.meta.globEager('../components/Base/*.vue')
componentList.forEach(async (component) => {
const asyncComponent = defineAsyncComponent(
() => import(`../components/Base/${component}.vue`)
)
app.component(component, asyncComponent)
})
}
you can also try glob that also work pretty well but I have checked it for this solution but check this out worth reading
Dynamic import
[Update]
I tried same with import.meta.globEage and it works only issue its little bit lazy loaded you may feel it loading slow but isn't noticeable much.
import { App, defineAsyncComponent } from 'vue'
export const registerComponents = async (app: App): void => {
Object.keys(import.meta.globEager('../components/Base/*.vue')).forEach(
async (component) => {
const asyncComponent = defineAsyncComponent(
() => import(/* #vite-ignore */ component)
)
app.component(
(component && component.split('/').pop()?.split('.')[0]) || '',asyncComponent
)
})
}
I would like to separate the business logic and the template of a component.
In React I would use the Container/Presentation pattern.
const Container = (props) => <Presentational ...props/>
But what is the equivalent with vue.js?
Say I have this all in one component (did not test this one, it just for example) :
<template>
<div id="app">
<div v-for="user in users">
{{user.name}}
</div>
</div>
</template>
<script>
Vue.component({
el: '#app',
props: {
filter: "foo"
},
data: {
users: [],
},
ready: function () {
this.$http.get('/path/to/end-point?filter='+this.props.filter)
.then(function (response) {
this.users = response.data
})
}
})
</script>
How I could extract a container with just the fetch logic?
I really don't see a need for a container component. Abstract your fetch code out into a vuex action and bind your store state within the component using computed properties.
You can extend any Vue component, which will allow you to override any methods from the parent. So, you can create a base component and then extend that:
const Base = Vue.component('base-comp', {
template: "#base",
data() {
return {
name: 'foo'
}
}
});
const Child = Base.extend({
data() {
return {
name: 'bar'
}
}
});
Vue.component('child-comp', Child)
You can check out the JSFiddle here: https://jsfiddle.net/tdgxdhz9/
If you are using single file components, then it's simply a case of importing the base component and extending it, which keeps the original template in tact:
import Base from './BaseComponent.vue'
Base.extend({
// Javascript code here
})
You can use vuex-connect to create container components like in React. Here an example of project : https://github.com/pocka/vue-container-component-example
What you are looking for is Vue Mixins.
You can write a mixins file which contains your business logic and import it into your Vue components.
Link:- https://v2.vuejs.org/v2/guide/mixins.html
I'm trying to design a store to manage the events of my Vuex application. This far, I have the following.
import Vue from "vue";
import Vuex from "vuex";
Vue.use(Vuex);
const state = { dataRows: [], activeDataRow: {} };
const mutations = {
UPDATE_DATA(state, data) { state.dataRows = data; state.activeDataRow = {}; },
};
export default new Vuex.Store({ state, mutations });
I'm going to have a number of list items that are supposed to change the value of the data in the store when clicked. The design of the root component App and the menu bar Navigation is as follows (there will be a bunch of actions in the end so I've collected them in the file actions.js).
<template>
<div id="app">
<navigation></navigation>
</div>
</template>
<script>
import navigation from "./navigation.vue"
export default { components: { navigation } }
</script>
<template>
<div id="nav-bar">
<ul>
<li onclick="console.log('Clickaroo... ');">Plain JS</li>
<li #click="updateData">Action Vuex</li>
</ul>
</div>
</template>
<script>
import { updateData } from "../vuex_app/actions";
export default {
vuex: {
getters: { activeDataRow: state => state.activeDataRow },
actions: { updateData }
}
}
</script>
Clicking on the first list item shows the output in the console. However, when clicking on the second one, there's nothing happening, so I'm pretty sure that the event isn't dispatched at all. I also see following error when the page's being rendered:
Property or method "updateData" is not defined on the instance but referenced during render. Make sure to declare reactive data properties in the data option.
I'm very new to Vuex so I'm only speculating. Do I need to put in reference to the updateData action in the store, alongside with state and mutations? How do I do that? What/where's the "data option" that the error message talks about? Isn't it my components state and it's properties?
Why the error
You are getting the error, because when you have <li #click="updateData"> in the template, it looks for a method updateData in the vue component which it does not find, so it throws the error. To resolve this, you need to add corresponding methods in the vue component like following:
<script>
import { updateData } from "../vuex_app/actions";
export default {
vuex: {
getters: { activeDataRow: state => state.activeDataRow },
actions: { updateData }
},
methods:{
updateData: () => this.$store.dispatch("updateData")
}
}
</script>
What this.$store.dispatch("updateData") is doing is calling your vuex actions as documented here.
What/where's the "data option"
You don't have any data properties defined, data properties for a vue component can be used, if you want to use that only in that component. If you have data which needs to be accessed across multiple components, you can use vuex state as I believe you are doing.
Following is the way to have data properties for a vue component:
<script>
import { updateData } from "../vuex_app/actions";
export default {
date: {
return {
data1 : 'data 1',
data2 : {
nesteddata: 'data 2'
}
}
}
vuex: {
getters: { activeDataRow: state => state.activeDataRow },
actions: { updateData }
},
methods:{
updateData: () => this.$store.dispatch("updateData")
}
}
</script>
You can use these data properties in the views, have computed properies based on it, or create watchers on it and many more.