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Pass dynamic and responsive props to dynamic components with v-bind! NuxtJS

Long story short(maybe it is not so short after all): on the same page I want to import and load dynamic components based on the selected module.
I have an object defined in the assets which contains the informations about the components that should be loaded for each module, it looks like this:
export const modules = {
module1: {
calls: {...},
components: [
{
url: 'shared/PreviewItem',
properties: [
{
name: 'width',
value: 'leftComponentWidth'
}
]
},
{
url: 'shared/ResizingDivider',
properties: []
},
{
url: 'forms/FormItem',
properties: [
{
name: 'width',
value: 'rightComponentWidth'
},
{
name: 'item',
value: 'item'
}
]
}
]
},
module2: {...}
}
Then I have my index page:
<template>
<div class="item-content">
<component
:is="component"
v-for="(component, i) in dataComponents"
:key="i"
v-bind="component.propertiesToPass"
#emit-action="emitAction($event)"
/>
</div>
</template>
<script>
export default {
data() {
return {
item: null,
rightComponentWidth: 50,
leftComponentWidth: 50,
dataComponents: []
}
},
created() {
this.importComponents()
},
methods: {
importComponents() {
this.dataComponents = []
modules[this.$route.params.module].components.forEach(
(component) => {
import(`~/components/${component.url}`).then((res) => {
res.default.propertiesToPass = []
component.properties.forEach((prop) => {
res.default.propertiesToPass.push({
[prop.name]: this[prop.value]
})
})
this.dataComponents.push(res.default)
})
}
)
},
emitAction(event) {
this[event.function](event.props)
},
changeComponentsWidth(event) {
this.leftComponentWidth -= event
this.rightComponentWidth = 100 - this.leftComponentWidth
}
}
}
}
</script>
As it is probably easy to understand I have to components and one divider between them that can be dragged to the right or to the left for resize the width of the other two components.
The components are getting loaded and imported correctly, and the props are passed right, so the width of both of the components in the start are 50 50.
The issue is that by doing [prop.name]: this[prop.value] I am setting the props to the value of this[prop.value] variable, and not to the variable itself, so, when I try to resize the components by using the divider, the variables get updated but the props get not.
Then the props are not responsive or reactive, are fixed.
The only way to update the props of the components is to add the following lines to the changeComponentsWidth() method:
this.dataComponents[0].propertiesToPass[0].width = this.leftComponentWidth
this.dataComponents[2].propertiesToPass[0].width = this.rightComponentWidth
But this is not a very dynamic way.
So My question is:
Is it possible to bind the props to the variable itself instead of just passing its value?
Or are there other "dynamic" ways to keep my props "responsive and reactive"?

Advanced Vue.js Dynamic Functional Component using `:is` syntax and render function

Background: I've built a standard single file component that takes a name prop and looks in different places my app's directory structure and provides the first matched component with that name. It was created to allow for "child theming" in my Vue.js CMS, called Resto. It's a similar principle to how WordPress looks for template files, first by checking the Child theme location, then reverting to the parent them if not found, etc.
Usage : The component can be used like this:
<!-- Find the PageHeader component
in the current child theme, parent theme,
or base components folder --->
<theme-component name="PageHeader">
<h1>Maybe I'm a slot for the page title!</h1>
</theme-component>
My goal : I want to convert to a functional component so it doesn't affect my app's render performance or show up in the Vue devtools. It looks like this:
<template>
<component
:is="dynamicComponent"
v-if="dynamicComponent"
v-bind="{ ...$attrs, ...$props }"
v-on="$listeners"
#hook:mounted="$emit('mounted')"
>
<slot />
</component>
</template>
<script>
import { mapGetters } from 'vuex'
export default {
name: 'ThemeComponent',
props: {
name: {
type: String,
required: true,
default: '',
},
},
data() {
return {
dynamicComponent: null,
resolvedPath: '',
}
},
computed: {
...mapGetters('site', ['getThemeName']),
customThemeLoader() {
if (!this.name.length) {
return null
}
// console.log(`Trying custom theme component for ${this.customThemePath}`)
return () => import(`#themes/${this.customThemePath}`)
},
defaultThemeLoader() {
if (!this.name.length) {
return null
}
// console.log(`Trying default component for ${this.name}`)
return () => import(`#restoBaseTheme/${this.componentPath}`)
},
baseComponentLoader() {
if (!this.name.length) {
return null
}
// console.log(`Trying base component for ${this.name}`)
return () => import(`#components/Base/${this.name}`)
},
componentPath() {
return `components/${this.name}`
}, // componentPath
customThemePath() {
return `${this.getThemeName}/${this.componentPath}`
}, // customThemePath()
},
mounted() {
this.customThemeLoader()
.then(() => {
// If found in the current custom Theme dir, load from there
this.dynamicComponent = () => this.customThemeLoader()
this.resolvedPath = `#themes/${this.customThemePath}`
})
.catch(() => {
this.defaultThemeLoader()
.then(() => {
// If found in the default Theme dir, load from there
this.dynamicComponent = () => this.defaultThemeLoader()
this.resolvedPath = `#restoBaseTheme/${this.defaultThemePath}`
})
.catch(() => {
this.baseComponentLoader()
.then(() => {
// Finally, if it can't be found, try the Base folder
this.dynamicComponent = () => this.baseComponentLoader()
this.resolvedPath = `#components/Base/${this.name}`
})
.catch(() => {
// If found in the /components dir, load from there
this.dynamicComponent = () => import(`#components/${this.name}`)
this.resolvedPath = `#components/${this.name}`
})
})
})
},
}
</script>
I've tried SO many different approaches but I'm fairly new to functional components and render functions (never got into React).
The roadblock : I can't seem to figure out how to run the chained functions that I call in my original mounted() function. I've tried running it from inside the render function with no success.
Big Question
How can I find and dynamically import the component I'm targeting before I pass that component to the createElement function (or within my single file <template functional><template/>)?
Thanks all you Vue-heads! ✌️
Update: I stumbled across this solution for using the h() render function and randomly loading a component, but I'm not sure how to make it work to accept the name prop...

Late to the party, but I was in a similar situation, where I had a component in charge of conditionally render one of 11 different child components:
<template>
<v-row>
<v-col>
<custom-title v-if="type === 'title'" :data="data" />
<custom-paragraph v-else-if="type === 'paragraph'" :data="data" />
<custom-text v-else-if="type === 'text'" :data="data" />
... 8 more times
</v-col>
</v-row>
</template>
<script>
export default {
name: 'ProjectDynamicFormFieldDetail',
components: {
CustomTitle: () => import('#/modules/path/to/CustomTitle'),
CustomParagraph: () => import('#/modules/path/to/CustomParagraph'),
CustomText: () => import('#/modules/path/to/CustomText'),
... 8 more times
},
props: {
type: {
type: String,
required: true,
},
data: {
type: Object,
default: null,
}
},
}
</script>
which of course is not ideal and pretty ugly.
The functional equivalent I came up with is the following
import Vue from 'vue'
export default {
functional: true,
props: { type: { type: String, required: true }, data: { type: Object, default: null } },
render(createElement, { props: { type, data } } ) {
// prop 'type' === ['Title', 'Paragraph', 'Text', etc]
const element = `Custom${type}`
// register the custom component globally
Vue.component(element, require(`#/modules/path/to/${element}`).default)
return createElement(element, { props: { data } })
}
}
Couple of things:
lazy imports don't seem to work inside Vue.component, hence require().default is the way to go
in this case the prop 'type' needs to be formatted, either in the parent component or right here

Building a form with Vuejs. Pass data from children to parent

I'm trying to build a form using "v-for" for input component and then generate a pdf file with PDFMake using data from inputs. But I didn't know how to pass the data from input component back to parent.
I read a lot of topics, but can't find a way to do this.
Here is short code without additional inputs, checkboxes etc. I plan to use around 15 inputs with different parameters to generate final PDF. Some of parameters also will be used to change final data depending of conditional statements.
Everything is work fine if code in one file, without loop and components. But not now.
Here is parent:
<template lang="pug">
.form
Input(v-for="data in form.client_info" v-bind:key="data.id" v-bind:data="data")
button(#click="pdfgen") Download PDF
</template>
<script>
export default {
components: {
Input: () => import('#/components/items/form/input')
},
data() {
return {
client_name: '',
client_email: '',
form: {
client_info: [
{id:'client_name', title:'Name'},
{id:'client_email', title: 'Email'},
{id:'foo', title: 'foo'}
],
}
}
},
methods: {
pdfgen: function () {
var pdfMake = require('pdfmake/build/pdfmake.js')
if (pdfMake.vfs == undefined) {
var pdfFonts = require('pdfmake/build/vfs_fonts.js')
pdfMake.vfs = pdfFonts.pdfMake.vfs;
}
if (this.foo) {
var foo = [
'Foo: ' + this.foo
];
} else {
foo = ''
]
}
var docDefinition = {
content: [
'Name: ' + this.client_name,
'Email: ' + this.client_email,
'\n',
foo
]
}
pdfMake.createPdf(docDefinition).download('Demo.pdf');
}
}
}
</script>
Here is a children (Input component):
<template lang="pug">
label.form_item
span.form_item_title {{ data.title }}
input.form_item_input(:v-model="data.id" type="text")
</template>
<script>
export default {
props: ['data']
}
</script>
Any ideas how to make it work?

You'll want to use a method that vue has build-in named $emit().
Before going into how to do that, a quick explanation. Because vue attempts to make data flow one-directional there is not a super quick way to just pass data back to a parent. What Vue proposes instead is to pass a method to the child component that, when called, will 'emit' the value it changed to it's parent and the parent can then do what it wants with that value.
So, in your parent component you'll want to add a method that will handle a change when the child emits. This could look something like:
onChildValueChanged(value){ this.someValue = value }
The value we passed to the function will be coming from our child component. We will need to define in our child component what this function should do. In your child component you could have a function that looks like so:
emitValueChange(event){ this.$emit('childFunctionCall', this.someChildValue) }
Next we need to tie those two functions together by adding an attribute on our child template. In this example that might look like:
<Child :parentData="someData" v-on:childFunctionCall="onChildValueChanged"></Child>
What that above template is doing is saying that when the function on:childFunctionCall is 'emited' then our function in the parent scope should fire.
Finally, in the child template we just need to add some event that calls out emiter. That could look like:
<button v-on:click="emitToParent">This is a button</button>
So when our button is clicked, the emiter is called. This triggers the function in our child component named 'emitToParent' which in turn calls the function we passed to our child component.
You'll have to tailor your use case to match the exam

I found a solution using Vuex.
So now my components look like this.
Here is parent:
<template lang="pug">
.form
Input(v-for="data in formClient" v-bind:key="data.id" v-bind:data="data")
button(#click="pdfgen") Download PDF
</template>
<script>
export default {
components: {
Input: () => import('#/components/items/form/input'),
store: () => import('#/store'),
},
computed: {
formClient() { return this.$store.getters.client }
}
}
</script>
Here is a children (Input component):
<template lang="pug">
label.form_item
span.form_item_title {{ data.title }}
input.form_item_input(v-model="data.value" :type="data.input_type")
</template>
<script>
export default {
props: ['data'],
computed: {
form: {
get () {
return this.$store.state.obj.message
},
set (value) {
this.$store.commit('updateMessage', value)
}
}
}
}
</script>
Here is a store module:
<script>
export default {
actions: {},
mutations: {},
state: {
form: {
client: [
{id:'client_name', title:'Name', value: ''},
{id:'client_email', title: 'Email', value: ''},
{id:'foo', title: 'foo', value: ''}
]
}
},
getters: {
client: state => {
return state.form.client;
}
}
}
</script>
Now I can read updated data from store directly from PDFMake function.

Dynamically changing props

On my app, I have multiple "upload" buttons and I want to display a spinner/loader for that specific button when a user clicks on it. After the upload is complete, I want to remove that spinner/loader.
I have the buttons nested within a component so on the file for the button, I'm receiving a prop from the parent and then storing that locally so the loader doesn't show up for all upload buttons. But when the value changes in the parent, the child is not getting the correct value of the prop.
App.vue:
<template>
<upload-button
:uploadComplete="uploadCompleteBoolean"
#startUpload="upload">
</upload-button>
</template>
<script>
data(){
return {
uploadCompleteBoolean: true
}
},
methods: {
upload(){
this.uploadCompleteBoolean = false
// do stuff to upload, then when finished,
this.uploadCompleteBoolean = true
}
</script>
Button.vue:
<template>
<button
#click="onClick">
<button>
</template>
<script>
props: {
uploadComplete: {
type: Boolean
}
data(){
return {
uploadingComplete: this.uploadComplete
}
},
methods: {
onClick(){
this.uploadingComplete = false
this.$emit('startUpload')
}
</script>

Fixed event name and prop name then it should work.
As Vue Guide: Custom EventName says, Vue recommend always use kebab-case for event names.
so you should use this.$emit('start-upload'), then in the template, uses <upload-button #start-upload="upload"> </upload-button>
As Vue Guide: Props says,
HTML attribute names are case-insensitive, so browsers will interpret
any uppercase characters as lowercase. That means when you’re using
in-DOM templates, camelCased prop names need to use their kebab-cased
(hyphen-delimited) equivalents
so change :uploadComplete="uploadCompleteBoolean" to :upload-complete="uploadCompleteBoolean"
Edit: Just noticed you mentioned data property=uploadingComplete.
It is easy fix, add one watch for props=uploadComplete.
Below is one simple demo:
Vue.config.productionTip = false
Vue.component('upload-button', {
template: `<div> <button #click="onClick">Upload for Data: {{uploadingComplete}} Props: {{uploadComplete}}</button>
</div>`,
props: {
uploadComplete: {
type: Boolean
}
},
data() {
return {
uploadingComplete: this.uploadComplete
}
},
watch: { // watch prop=uploadComplete, if change, sync to data property=uploadingComplete
uploadComplete: function (newVal) {
this.uploadingComplete = newVal
}
},
methods: {
onClick() {
this.uploadingComplete = false
this.$emit('start-upload')
}
}
})
new Vue({
el: '#app',
data() {
return {
uploadCompleteBoolean: true
}
},
methods: {
upload() {
this.uploadCompleteBoolean = false
// do stuff to upload, then when finished,
this.uploadCompleteBoolean = true
},
changeStatus() {
this.uploadCompleteBoolean = !this.uploadCompleteBoolean
}
}
})
<script src="https://cdnjs.cloudflare.com/ajax/libs/vue/2.5.16/vue.js"></script>
<div id="app">
<button #click="changeStatus()">Toggle Status {{uploadCompleteBoolean}}</button>
<p>Status: {{uploadCompleteBoolean}}</p>
<upload-button :upload-complete="uploadCompleteBoolean" #start-upload="upload">
</upload-button>
</div>

The UploadButton component shouldn't have uploadingComplete as local state (data); this just complicates the component since you're trying to mix the uploadComplete prop and uploadingComplete data.
The visibility of the spinner should be driven by the parent component through the prop, the button itself should not be responsible for controlling the visibility of the spinner through local state in response to clicks of the button.
Just do something like this:
Vue.component('upload-button', {
template: '#upload-button',
props: ['uploading'],
});
new Vue({
el: '#app',
data: {
uploading1: false,
uploading2: false,
},
methods: {
upload1() {
this.uploading1 = true;
setTimeout(() => this.uploading1 = false, Math.random() * 1000);
},
upload2() {
this.uploading2 = true;
setTimeout(() => this.uploading2 = false, Math.random() * 1000);
},
},
});
<script src="https://rawgit.com/vuejs/vue/dev/dist/vue.js"></script>
<div id="app">
<upload-button :uploading="uploading1" #click="upload1">Upload 1</upload-button>
<upload-button :uploading="uploading2" #click="upload2">Upload 2</upload-button>
</div>
<template id="upload-button">
<button #click="$emit('click')">
<template v-if="uploading">Uploading...</template>
<slot v-else></slot>
</button>
</template>

Your question seems little bit ambiguë, You can use watch in that props object inside the child component like this:
watch:{
uploadComplete:{
handler(val){
//val gives you the updated value
}, deep:true
},
}
by adding deep to true it will watch for nested properties in that object, if one of properties changed you ll receive the new prop from val variable
for more information : https://v2.vuejs.org/v2/api/#vm-watch
if not what you wanted, i made a real quick example,
check it out hope this helps : https://jsfiddle.net/K_Younes/64d8mbs1/

How to access data property of vue component

I am new to Vue.js and I think its amazing. I have been tasked to start implementing some vue components in our non-greenfield web application and I thought I would start by implementing some self-contained "widgets" that have to deal heavily with state in my work's rails app.
Its working great as a self-contained component but I want to load it with a data attribute so the component know what it needs to deal with. My Vue file looks like (I have redacted parts of this due to IP concerns):
<template>
<div class="card">
<div class="card-body">
${{ b.id }}
</div>
<div class="card-footer bg--blue-sky">
${{ b.amount }}
</div>
</div>
</template>
<script>
export default {
data: function () {
return {
errors: [],
b: {
id: null,
amount: null
}
}
},
// Fetches posts when the component is created.
created: function () {
jQuery.ajax({
url: "/api/b/" + '2' + ".json",
method: 'GET',
dataType: "json"
})
.then(response => {
this.b = response.b
})
.catch(e => {
this.errors.push(e)
});
}
}
</script>
<style scoped>
</style>
The component is registered with:
import FiDis from '../components/fi_dis.vue'
Vue.component('fi_dis', FiDis);
document.addEventListener('turbolinks:load', () => {
const fi_dis = new Vue({
el: '#bs',
components: { FiDis }
})
});
And in my html.erb code I create the components with:
<div id="bs" policy="2">
<fi_dis data-b-id="1"></fi_dis>
<fi_dis data-b-id="2"></fi_dis>
</div>
This all works flawlessly, and does exactly what I want it to do except for one thing. I want to access the data-b-id attribute within the created function of the component (i.e. replace the number '2' in the url of the ajax call above with the value form the attribute). In this way, I hope for the component to handle ANY "fi_dis" I choose, merely by specifying the b-id in the data attribute I want it to handle.
How can I achieve this?

You communicate data values passing props from parent component to child components.
So for example you should define which props your component is allowed to receive:
import FiDis from '../components/fi_dis.vue'
Vue.component('fi_dis', FiDis);
document.addEventListener('turbolinks:load', () => {
const fi_dis = new Vue({
el: '#bs',
components: { FiDis },
props['bId'],
created() { // This is a lifecycle method
this.printPropertyValue();
},
methods: {
// Your custom methods goes here separeted by commas
printPropertyValue() {
console.log(this.bId);
}
}
})
});
And the sintax for passing the data from the component implementation is using v-bind:propertyName or :propertyName (short hand).
<div id="bs" policy="2">
<fi_dis :bId="1"></fi_dis>
<fi_dis :bId="2"></fi_dis>
</div>