I'm new to Vue and using Vue 2.2.1. I am wondering if it's possible to create a reusable component that can have its layout defined by its parent. For example, consider the following pseudo code:
// Parent template
<template>
<ul>
<li v-for="item in items">
<item-component :id="item.id">
<h1><item-title /></h1>
<p>
<item-description />
</p>
</item-component>
</li>
</ul>
</template>
// Child definition
<script>
export default {
data() {
return {
title: '',
description: ''
}
}
create() {
// do some async fetch
fetch(this.id)
.then((result) {
this.$data.title = result.title
this.$data.description = result.description
})
}
}
</script>
So, the use case is that the child component is responsible for the fetching of the data by id, but the parent is responsible for laying out the data. This way, I can keep the fetch logic in one place, but reformat the data however I want in various places.
Not sure if this is possible or not. I suppose I can extract the child's fetching functionality out into a mixin, but then I'd have to create a new component for each layout variation. What is the recommended way to handle this in Vue?
In general, when you want the parent to include content in the child, the means to do it is via a slot. Inside, a typical slot, however, the scope is the parent's scope, meaning it does not have access to data inside the child.
In your case, you would want to use a scoped slot, which is where the child is able to pass some information back to the parent to use.
// Parent template
<template>
<ul>
<li v-for="item in items">
<item-component :id="item.id">
<template scope="props">
<h1>{{props.title}}</h1>
<p>
{{props.description}}
</p>
</template>
</item-component>
</li>
</ul>
</template>
// Child definition
<script>
export default {
template:"<div><slot :title='title' :description='description'></slot></div>",
data() {
return {
title: '',
description: ''
}
}
create() {
// do some async fetch
fetch(this.id)
.then((result) {
this.$data.title = result.title
this.$data.description = result.description
})
}
}
</script>
Related
i am trying to send and render some data from a child component to another child component & both components are rendered using one main component , how can i pass the data between two child components (in my vue app)?
exg
I have two child components A & B , "B" has click add to cart click event and have data of cart items , & i have template for cart item in component "A"
In this situation, as both components share the same parent, it's common to move whatever shared state you need into the parent component and pass to the children as props.
Where components don't shared a direct parent, you can use an event bus (for very small apps) or Vuex. Vuex lets you share state between components in your app without having to pass props down through multiple levels.
There are a lot of ways to achieve this. I am explaining with global even bus concept. Following is an example. Here, child A and child B are communicating through event bus
const eventBus = new Vue ()
Vue.component('ChildB',{
template:`
<div id="child-b">
<h2>Child B</h2>
<pre>data {{ this.$data }}</pre>
<hr/>
</div>`,
data() {
return {
score: 0
}
},
created () {
eventBus.$on('updatingScore', this.updateScore) // 3.Listening
},
methods: {
reRender() {
this.$forceUpdate()
},
updateScore(newValue) {
this.score = newValue
}
}
})
Vue.component('ChildA',{
template:`
<div id="child-a">
<h2>Child A</h2>
<pre>data {{ this.$data }}</pre>
<hr/>
<button #click="changeScore">Change Score</button>
<span>Score: {{ score }}</span>
</div>`,
props: ["score"],
methods: {
changeScore() {
this.score +=200;
eventBus.$emit('updatingScore', this.score+ 200)
}
}
})
Vue.component('ParentA',{
template:`
<div id="parent-a">
<h2>Parent A</h2>
<pre>data {{ this.$data }}</pre>
<hr/>
<child-a :score="score"/>
<child-b/>
</div>`,
data() {
return {
score: 100
}
}
})
Vue.component('GrandParent',{
template:`
<div id="grandparent">
<h2>Grand Parent</h2>
<pre>data {{ this.$data }}</pre>
<hr/>
<parent-a/>
</div>`,
})
new Vue ({
el: '#app',
})
<script src="https://cdnjs.cloudflare.com/ajax/libs/vue/2.5.17/vue.js"></script>
<div id="app">
<grand-parent/>
</div>
Ideally, you should use Vuex as state management pattern.
But if your application is very simple and you don't need to do those operations often, you can pass data in emit payload from child to parent, and then parent component should pass it to another child via props
I have the vue component with $emit into component and let it return the data from the component. I will use the component to update current page's data. the codes below
Template:
<Testing
#update="update">
</Testing>
<AnotherComponent
:data="text"
>
</AnotherComponent>
Script:
method(){
update: function(data){
this.text = data.text
}
}
it work perfectly if only this one.
Now , i need to make a button to add one more component.
I use the for loop to perform this.
Template
<div v-for="index in this.list">
<Testing
:name="index"
#update="update">
</Testing>
<AnotherComponent
:data="text"
>
</AnotherComponent>
</div>
Script:
method(){
addList : function(){
this.list +=1;
},
deleteList : function(){
this.list -=1;
},
update: function(data){
this.text = data.text
}
}
The add and delete function run perfectly.
However , they share the "update" method and the "text" data.
so , If I change the second component , the first component will also changed.
I think this is not the good idea to copy the component.
Here are my requirements.
This component is the part of the form, so they should have different name for submit the form.
The another component" will use the data from the "testing component" to do something. the "testing" and "another component" should be grouped and the will not change any data of another group.
Any one can give me the suggestion how to improve these code? Thanks
What happends is that both are using the data form the parent, and updating that same data.
It seems that you are making some kind of custom inputs. In that case in your child component you can use 'value' prop, and 'input' event, and in the parent user v-model to keep track of that especific data data.
Child component BaseInput.vue:
<template>
<div>
<input type="text" :value="value" #keyup="inputChanged">
</div>
</template>
<script>
export default {
props: ['value'],
data () {
return {
}
},
methods: {
inputChanged (e) {
this.$emit('input', e.target.value)
}
}
}
</script>
And this is the code on the parent:
<template>
<div class="container">
<div class="row">
<div class="col-xs-12 col-sm-8 col-sm-offset-2 col-md-6 col-md-offset-3">
<base-input v-model="firstInputData"></base-input>
<p>{{ firstInputData }}</p>
<hr>
<base-input v-model="secondInputData"></base-input>
<p>{{ secondInputData }}</p>
</div>
</div>
</div>
<script>
import BaseInput from './BaseInput.vue'
export default {
components: {BaseInput},
data() {
return{
firstInputData: 'You can even prepopulate your custom inputs',
secondInputData: ''
}
}
}
</script>
In the parent you could really store the diferent models in an object as properties, and pass that object to that "The another component" , pass them as individual props... pass an array ....
This is an easy question but I dont know the best way to do it correctly with Vue2:
Parent Component:
<template>
<div class="parent">
<child></child>
{{value}} //How to get it
</div>
</template>
Child Component:
<template>
<div class="child">
<p>This {{value}} is 123</p>
</div>
</template>
<script>
export default {
data: function () {
return { value: 123 }
}
}
</script>
Some ways you can achieve this include:
You can access the child VM directly via a ref, but this gets hairy because the ref won't be populated until the child component has mounted, and $refs isn't reactive, meaning you'd have to do something hacky like this:
<template>
<div class="parent">
<child ref="child"></child>
<template v-if="mounted">{{ $refs.child.value }}</template>
</div>
</template>
data() {
return {
mounted: false
}
},
mounted() {
this.mounted = true;
}
$emit the value from within the child component so that the parent can obtain the value when it is ready or whenever it changes.
Use Vuex (or similar principles) to share state across components.
Redesign the components so that the data you want is owned by the parent component and is passed down to the child via a prop binding.
(Advanced) Use portal-vue plugin when you want to have fragments of a component's template to exist elsewhere in the DOM.
Child components pass data back up the hierarchy by emitting events.
For example, in the parent, listen for an event and add the child value to a local one (an array for multiple child elements would be prudent), eg
<child #ready="childVal => { value.push(childVal) }"></child>
and in the child component, $emit the event on creation / mounting, eg
mounted () {
this.$emit('ready', this.value)
}
Demo ~ https://jsfiddle.net/p2jojsrn/
My first component (child component) like this :
<template>
...
</template>
<script>
export default {
...
methods: {
addPhoto() {
const data = { id_product: this.idProduct}
const item = this.idImage
this.$store.dispatch('addImage', data)
.then((response) => {
this.$parent.$options.methods.createImage(item, response)
});
},
}
}
</script>
If the method addPhoto called, it will call ajax and then it will get response ajax
I want to send response ajax and another parameter to method createImage. Method createImage is located in parent component (second component)
My second component (parent component) like this :
<template>
<div>
<ul class="list-inline list-photo">
<li v-for="item in items">
<div v-if="clicked[item]">
<img :src="image[item]" alt="">
<span class="fa fa-check-circle"></span>
</div>
<a v-else href="javascript:;" class="thumb thumb-upload"
title="Add Photo">
<span class="fa fa-plus fa-2x"></span>
</a>
</li>
</ul>
</div>
</template>
<script>
export default {
...
data() {
return {
items: [1,2,3,4,5],
clicked: [], // using an array because your items are numeric
test: null
}
},
methods: {
createImage(item, response) {
console.log(item)
this.$set(this.clicked, item, true)
this.test = item
},
}
}
</script>
If the code executed, it success call createImage method on parent component. The console log display value of item
But my problem is the data on parent component not success updated
How can I solve this problem?
You really should get in the habit of using events instead of directly accessing the parent component from a child.
In your case, it would be simple to emit an event in the then handler of the child's async request:
.then((response) => {
this.$emit('imageAdded', item);
});
And listen for it in the parent scope:
<child-component #itemAdded="createImage"></child-component>
That way, any component that uses that child component can react to its imageAdded event. Plus, you won't ever need to spend time debugging why the createImage method is firing when it's never being called in the Vue instance.
Your code isn't working because the way you are invoking the createImage method means that the this inside the function will not be referencing the parent component instance when it is called. So setting this.clicked or this.test will not affect the parent instance's data.
To call the parent component's function with the right context, you would need to do this:
this.$parent.createImage(item, response)
I have just started using Vue and experienced some unexpected behavior. On passing props from a parent to child component, I was able to access the prop in the child's template, but not the child's script. However, when I used the v-if directive in the parents template (master div), I was able to access the prop in both the child script and child template. I would be grateful for some explanation here, is there a better was of structuring this code? See below code. Thanks.
Parent Component:
<template>
<div v-if="message">
<p>
{{ message.body }}
</p>
<answers :message="message" ></answers>
</div>
</template>
<script>
import Answers from './Answers';
export default {
components: {
answers: Answers
},
data(){
return {
message:""
}
},
created() {
axios.get('/message/'+this.$route.params.id)
.then(response => this.message = response.data.message);
}
}
</script>
Child Component
<template>
<div class="">
<h1>{{ message.id }}</h1> // works in both cases
<ul>
<li v-for="answer in answers" :key="answer.id">
<span>{{ answer.body }}</span>
</li>
</ul>
</div>
</template>
<script>
export default{
props:['message'],
data(){
return {
answers:[]
}
},
created(){
axios.get('/answers/'+this.message.id) //only worls with v-if in parent template wrapper
.then(response => this.answers = response.data.answers);
}
}
</script>
this.message.id only works with v-if because sometimes message is not an object.
The call that you are making in your parent component that retrieves the message object is asynchronous. That means the call is not finished before your child component loads. So when your child component loads, message="". That is not an object with an id property. When message="" and you try to execute this.message.id you get an error because there is no id property of string.
You could continue to use v-if, which is probably best, or prevent the ajax call in your child component from executing when message is not an object while moving it to updated.