Can't get a reset button to clear out a checkbox - vue.js

I'm using Vue.js v2 and I've defined a single-file component, RegionFacet.vue. It lists some regions that relate to polygons on a map (click a value, the corresponding polygon appears on the map).
Separately, I have a reset button. When that gets clicked, I call a method in RegionFacet to unselect any checkboxes displayed by RegionFacet. The model does get updated, however, the checkboxes remain checked. What am I missing?
<template>
<div class="facet">
<div class="">
<div class="panel-group" id="accordion">
<div class="panel panel-default">
<div class="panel-heading">
<a data-toggle="collapse"v-bind:href="'#facet-' + this.id"><h4 class="panel-title">Regions</h4></a>
</div>
<div v-bind:id="'facet-' + id" class="panel-collapse collapse in">
<ul class="list-group">
<li v-for="feature in content.features" class="list-group-item">
<label>
<input type="checkbox" class="rChecker"
v-on:click="selectRegion"
v-bind:value="feature.properties.name"
v-model="selected"
/>
<span>{{feature.properties.name}}</span>
</label>
</li>
</ul>
</div>
</div>
</div>
</div>
</div>
</template>
<script>
export default {
props: ['content'],
data: function() {
return {
id: -1,
selected: []
}
},
methods: {
selectRegion: function(event) {
console.log('click: ' + event.target.checked);
if (event.target.checked) {
this.selected.push(event.target.value);
} else {
var index = this.selected.indexOf(event.target.value);
this.selected.splice(index, 1);
}
this.$emit('selection', event.target.value, event.target.checked);
},
reset: function() {
this.selected.length = 0;
}
},
created: function() {
this.id = this._uid
}
}
</script>
<style>
</style>

You are directly setting the array length to be zero, which cannot be detected by Vue, as explained here: https://v2.vuejs.org/v2/guide/list.html#Caveats
Some more info: https://v2.vuejs.org/v2/guide/reactivity.html#Change-Detection-Caveats
To overcome this, you may instead set the value of this.selected as follows:
reset: function() {
this.selected = [];
}

Related

Vue cli 3 props (parent to child) child never update after the variable in parent has changed

I tried to make a chat app using Vue CLI 3 and I have finished making a real-time chat room. Then, I tried to give a citing function to it which users can cite the message before and reply to it. So, I manage to pass the cited message to the child component by props. The cited message was NULL by default. After the user clicked some buttons, I expected the value of the "cited message" would change and the new value would be passed to the child through props (automatically updated). But, in fact, it didn't.
When I was browsing the internet, I did find several questions about updating the child component when props values change. So, I tried watch:, created(), update(), but none of them worked.
I once tried to directly add an element <p> in the child component and put {{cited_message}} in it to see what was inside the variable. Then, the Vue app crashed with a white blank page left (but the console didn't show any error).
For convenience, I think the problem is around:
<CreateMessage:name="name":cited_message="this.cited_message"#interface="handleFcAfterDateBack"/>
OR
props: ["name","cited_message"],
watch: { cited_message: function (newValue){ this.c_message = newValue; } },
You can ctrl+F search for the above codes to save your time.
Parent component:
<template>
<div class="container chat">
<h2 class="text-primary text-center">Real-time chat</h2>
<h5 class="text-secondary text-center">{{ name }}</h5>
<div class="card" style="min-height: 0.8vh">
<div class="card-body">
<p class="text-secondary nomessages" v-if="messages.length == 0">
[no messages yet!]
</p>
<div class="messages" v-chat-scroll="{ always: false, smooth: false }">
<div v-for="message in messages" :key="message.id">
<div v-if="equal_name(message)">
<div class="d-flex flex-row">
<div class="text-info">
[ {{ message.name }} ] : {{ message.message }}
</div>
<div class="btn-group dropright">
<a
class="btn btn-secondary btn-sm dropdown-toggle"
href="#"
role="button"
id="dropdownMenuLink"
data-toggle="dropdown"
aria-haspopup="true"
aria-expanded="false"
>
</a>
<div class="dropdown-menu" aria-labelledby="dropdownMenuLink">
<button
#click="get_cited_message(message)"
:key="message.id"
class="dropdown-item"
href="#"
>
Cite
</button>
</div>
</div>
<div class="text-secondary time">
<sub>{{ message.timestamp }}</sub>
</div>
</div>
<!--below is for cited message-->
<div v-if="message.cited_message" class="d-flex flex-row">
Cited : {{ message.cited_message }}
</div>
</div>
<div v-else>
<div class="d-flex flex-row-reverse">
<div class="text-info">
[ {{ message.name }} ] : {{ message.message }}
</div>
<div class="text-secondary time">
<sub>{{ message.timestamp }}</sub>
</div>
</div>
</div>
</div>
</div>
</div>
<div class="card-action">
<CreateMessage
:name="name"
:cited_message="this.cited_message"
#interface="handleFcAfterDateBack"
/>
</div>
</div>
</div>
</template>
<script>
import CreateMessage from "#/components/CreateMessage";
import fb from "#/firebase/init.js";
import moment from "moment";
export default {
name: "Chat",
props: {
name: String,
},
components: {
CreateMessage,
},
methods: {
equal_name(message) {
if (message.name == this.name) {
return true;
} else {
return false;
}
},
get_cited_message(message) {
this.cited_message = message.message;
console.log(this.cited_message);
},
handleFcAfterDateBack(event) {
console.log("data after child handle: ", event);
},
},
data() {
return {
messages: [],
cited_message: null,
};
},
created() {
let ref = fb.collection("messages").orderBy("timestamp");
ref.onSnapshot((snapshot) => {
snapshot.docChanges().forEach((change) => {
change.type = "added";
if (change.type == "added") {
let doc = change.doc;
this.messages.push({
id: doc.id,
name: doc.data().name,
message: doc.data().message,
timestamp: moment(doc.data().timestamp).format(
"MMMM Do YYYY, h:mm:ss a"
),
cited_message: doc.data().cited_message,
});
}
});
});
},
};
</script>
<style>
.chat h2 {
font-size: 2.6em;
margin-bottom: 0px;
}
.chat h5 {
margin-top: 0px;
margin-bottom: 40px;
}
.chat span {
font-size: 1.2em;
}
.chat .time {
display: block;
font-size: 0.7em;
}
.messages {
max-height: 300px;
overflow: auto;
text-align: unset;
}
.d-flex div {
margin-left: 10px;
}
</style>
Child component:
<template>
<div class="container" style="margin-bottom: 30px">
<form #submit.prevent="createMessage()">
<div class="form-group">
<input
type="text"
name="message"
class="form-control"
placeholder="Enter your message"
v-model="newMessage"
/>
<p v-if="c_message" class="bg-secondary text-light">Cited: {{c_message}}</p>
<p class="text-danger" v-if="errorText">{{ errorText }}</p>
</div>
<button class="btn btn-primary" type="submit" name="action">
Submit
</button>
</form>
</div>
</template>
<script>
import fb from "#/firebase/init.js";
import moment from "moment";
export default {
name: "CreateMessage",
props: ["name","cited_message"],
watch: {
cited_message: function (newValue){
this.c_message = newValue;
}
},
data() {
return {
newMessage: "",
errorText: null,
c_message: null
};
},
methods: {
createMessage() {
if (this.newMessage) {
fb.collection("messages")
.add({
message: this.newMessage,
name: this.name,
timestamp: moment().format(),
cited_message: this.c_message
})
.then(function(docRef) {
console.log("Document written with ID: ", docRef.id);
})
.catch((err) => {
console.log(err);
});
this.newMessage = null;
this.errorText = null;
} else {
this.errorText = "Please enter a message!";
}
},
},
beforeMount(){
this.c_message = this.cited_message;
}
};
</script>
Side-note: In the parent component, I only made the dropdown menu for the messages on the left-hand side. If this thread solved, I would finish the right-hand side.
It is solved. I think the problem is that the child component didn't re-render when the variable in parent component updated. Only the parent component was re-rendered. So, the props' values in the child remained the initial values. In order to solve this, binding the element with v-bind:key can let the Vue app track the changes of the variable (like some kind of a reminder that reminds the app to follow the changes made on the key). When the variable(key) changes, the app will be noticed and the new value will be passed to the child.
E.g.
Original
<CreateMessage
:name="name"
:cited_message="this.cited_message"
#interface="handleFcAfterDateBack"
/>
Solved
<CreateMessage
:name="name"
:cited_message="this.cited_message"
#interface="handleFcAfterDateBack"
:key="this.cited_message"
/>
Even though the problem is solved, I don't know whether I understand the problem clearly. If I made any mistakes, please comment and let me know.

Pagination for dynamically generated content

Consider the following code.
<template>
<div class="card-container">
<div class="row">
<div class="col s12">
<a #click="addCard()">Add Card</a>
</div>
</div>
<div class="row">
<div v-for="(card, index) in cards" :key="index">
<div class="card-panel">
<span class="card-title">Card Title</span>
<div class="card-action">
<a #click="deleteCard(index)">Delete</a>
</div>
</div>
</div>
</div>
</div>
</template>
<script>
export default {
data: function() {
return {
cards: []
}
},
methods: {
addCard: function() {
this.cards.push({
description: "",
});
},
deleteCard: function(index) {
this.cards.splice(index,1);
}
},
}
</script>
How to make the cards be grouped so that there are 4 rows and each row contains 4 cards? Upon reaching the fourth row the new cards go to the next page.
I thought I could use something like this codepen.io/parths267/pen/bXbWVv
But I have no idea how to get these cards organized in a pagination system.
The view would look something like this
My solution is calculate all cards of current page ahead.
Uses computed property to calculate the relate values which the pagination needs.
In below simple example (it is only one example, you need to add necessary validations as your actual needs, like boundary conditions) :
pages is the page count
cardsOfCurPage is the cards in current page
Then add one data property=pageIndex save the index of current page.
Anyway, keep data-driven in your mind.
List all arguments your pagination needs,
then declare them in data property or computed property.
execute the necessary calculations in computed property or methods.
PS: I don't know which css framework you uses, so I uses bootstrap instead.
Vue.component('v-cards', {
template: `<div class="card-container">
<div class="row">
<div class="col-12">
<a class="btn btn-danger" #click="addCard()">Add Card</a><span>Total Pages: {{pages}} Total Cards: {{cards.length}} Page Size:<input v-model="pageSize" placeholder="Page Size"></span>
</div>
</div>
<div class="row">
<div v-for="(card, index) in cardsOfCurrPage" :key="index" class="col-3">
<div class="card-panel">
<span class="card-title">Card Title: {{card.description}}</span>
<div class="card-action">
<a #click="deleteCard(index)">Delete</a>
</div>
</div>
</div>
</div>
<p><a class="badge" #click="gotoPrev()">Prev</a>- {{pageIndex + 1}} -<a class="badge" #click="gotoNext()">Next</a></p>
</div>`,
data: function() {
return {
cards: [],
pageSize: 6,
pageIndex: 0
}
},
computed: {
pages: function () {
return Math.floor(this.cards.length / this.pageSize) + 1
},
cardsOfCurrPage: function () {
return this.cards.slice(this.pageSize * this.pageIndex, this.pageSize * (this.pageIndex+1))
}
},
methods: {
addCard: function() {
this.cards.push({
description: this.cards.length,
});
},
deleteCard: function(index) {
this.cards.splice(index,1);
},
gotoPrev: function() {this.pageIndex -=1},
gotoNext: function() {this.pageIndex +=1}
},
})
new Vue({
el: '#app',
data() {
return {
}
}
})
<script src="https://cdnjs.cloudflare.com/ajax/libs/vue/2.5.17/vue.js"></script>
<link href="https://stackpath.bootstrapcdn.com/bootstrap/4.5.0/css/bootstrap.min.css" rel="stylesheet" />
<div id="app">
<v-cards></v-cards>
</div>

Bind class item in the loop

i want to bind my button only on the element that i added to the cart, it's working well when i'm not in a loop but in a loop anything happen. i'm not sure if it was the right way to add the index like that in order to bind only the item clicked, if i don't put the index every button on the loop are binded and that's not what i want in my case.
:loading="isLoading[index]"
here the vue :
<div class="container column is-9">
<div class="section">
<div class="columns is-multiline">
<div class="column is-3" v-for="(product, index) in computedProducts">
<div class="card">
<div class="card-image">
<figure class="image is-4by3">
<img src="" alt="Placeholder image">
</figure>
</div>
<div class="card-content">
<div class="content">
<div class="media-content">
<p class="title is-4">{{product.name}}</p>
<p class="subtitle is-6">Description</p>
<p>{{product.price}}</p>
</div>
</div>
<div class="content">
<b-button class="is-primary" #click="addToCart(product)" :loading="isLoading[index]"><i class="fas fa-shopping-cart"></i> Ajouter au panier</b-button>
</div>
</div>
</div>
</div>
</div>
</div>
</div>
here the data :
data () {
return {
products : [],
isLoading: false,
}
},
here my add to cart method where i change the state of isLoading :
addToCart(product) {
this.isLoading = true
axios.post('cart/add-to-cart/', {
data: product,
}).then(r => {
this.isLoading = false
}).catch(e => {
this.isLoading = false
});
}
You can change your isLoading to an array of booleans, and your addToCart method to also have an index argument.
Data:
return {
// ...
isLoading: []
}
Methods:
addToCart(product, index) {
// ...
}
And on your button, also include index:
#click="addToCart(product, index)"
By changing isLoading to an empty array, I don't think isLoading[index] = true will be reactive since index on isLoading doesn't exist yet. So you would use Vue.set in your addToCart(product, index) such as:
this.$set(this.isLoading, index, true)
This will ensure that changes being made to isLoading will be reactive.
Hope this works for you.
add on data productsLoading: []
on add to cart click, add loop index to productsLoading.
this.productsLoading.push(index)
after http request done, remove index from productsLoading.
this.productsLoading.splice(this.productoading.indexOf(index), 1)
and check button with :loading=productsLoading.includes(index)
You can create another component only for product card,
for better option as show below
Kindly follow this steps.
place the content of card in another vue component as shown below.
<!-- Product.vue -->
<template>
<div class="card">
<div class="card-image">
<figure class="image is-4by3">
<img src="" alt="Placeholder image">
</figure>
</div>
<div class="card-content">
<div class="content">
<div class="media-content">
<p class="title is-4">{{product.name}}</p>
<p class="subtitle is-6">Description</p>
<p>{{product.price}}</p>
</div>
</div>
<div class="content">
<b-button class="is-primary" #click="addToCart(product)" :loading="isLoading"><i class="fas fa-shopping-cart"></i> Ajouter au panier</b-button>
</div>
</div>
</div>
</templete>
<script>
export default {
name: "Product",
data() {
return {
isLoading: false
}
},
props: {
product: {
type: Object,
required: true
}
},
methods: {
addToCart(product) {
this.isLoading = true
axios.post('cart/add-to-cart/', {
data: product,
}).then(r => {
this.isLoading = false
}).catch(e => {
this.isLoading = false
});
}
}
}
</script>
Change your component content as shown below.
<template>
<div class="container column is-9">
<div class="section">
<div class="columns is-multiline">
<div class="column is-3" v-for="(product, index) in computedProducts">
<product :product="product" />
</div>
</div>
</div>
</div>
</templete>
<script>
import Product from 'path to above component'
export default {
components: {
Product
}
}
</script>
so in the above method you can reuse the component in other components as well.
Happy coding :-)

Click Event on Dynamically Generated Button Don't get fired in Vue

I am adding a button dynamically and attaching the click event but it doesn't seem to fire.
I see something similar on link below but its not exactly what I am looking for.
Vue: Bind click event to dynamically inserted content
let importListComponent = new Vue({
el: '#import-list-component',
data: {
files: [],
},
methods: {
// more methods here from 1 to 5
//6. dynamically create Card and Commit Button
showData: function (responseData) {
let self = this;
responseData.forEach((bmaSourceLog) => {
$('#accordionOne').append(`<div class="main-card mb-1 card">
<div class="card-header" id=heading${bmaSourceLog.bmaSourceLogId}>
${bmaSourceLog.fileName}
<div class="btn-actions-pane-right actions-icon-btn">
<input type="button" class="btn btn-outline-primary mr-2" value="Commit" v-on:click="commit(${bmaSourceLog.bmaSourceLogId})" />
<a data-toggle="collapse" data-target="#collapse${ bmaSourceLog.bmaSourceLogId}" aria-expanded="false" aria-controls="collapse${bmaSourceLog.bmaSourceLogId}" class="btn-icon btn-icon-only btn btn-link">
</a>
</div>
</div>
<div id="collapse${ bmaSourceLog.bmaSourceLogId}" class="collapse show" aria-labelledby="heading${bmaSourceLog.bmaSourceLogId}" data-parent="#accordionOne">
<div class="card-body">
<div id="grid${ bmaSourceLog.bmaSourceLogId}" style="margin-bottom:30px"></div>
</div>
</div>
</div>`);
});
},
//7. Commit Staging data
commit: function (responseData) {
snackbar("Data Saved Successfully...", "bg-success");
},
}});
I am adding button Commit as shown in code and want commit: function (responseData) to fire.
I was able to achieve this by pure Vue way. So my requirement was dynamically add content with a button and call a function from the button. I have achieved it like so.
Component Code
const users = [
{
id: 1,
name: 'James',
},
{
id: 2,
name: 'Fatima',
},
{
id: 3,
name: 'Xin',
}]
Vue.component('user-component', {
template: `
<div class="main-card mb-1 card">
<div class="card-header">
Component Header
<div class="btn-actions-pane-right actions-icon-btn">
<input type="button" class="btn btn-outline-primary mr-2" value="Click Me" v-on:click="testme(user.id)" />
</div>
</div>
<div class="card-body">
{{user.name}}
</div>
<div class="card-footer">
{{user.id}}
</div>
</div>
`
,props: {
user: Object
}
,
methods: {
testme: function (id) {
console.log(id);
}
}});
let tc = new Vue({
el: '#test-component',
data: {
users
},});
HTML
<div id="test-component">
<user-component v-for="user in users" v-bind:key="user.id" :user="user" />
</div>

Vue component data property not updating after parent data changes

I have a vue component (card-motor) with a prop named motor:
<div v-for="chunk in chunkDataMotores" class="row">
<div v-for="motor in chunk" class="col-md-6">
<card-motor :motor="motor"></card-motor>
</div>
</div>
Whenever data (motor) changes on the parent, the changes on the data property (id_color, id_motor, nombre _motor, etc...) of the component does not get updated. Here the card-motor component:
<template>
<div class="card" :data-motor-id="id_motor">
<div class="card-header" :style="backgroundColor">
<h4 class="text-center">{{nombre_motor}}<button class="btn btn-dark btn-sm pull-right" :data-motor-id="id_motor" #click="show_modal_colores(id_motor)">Color motor</button></h4>
</div>
<div class="card-body">
<div class="card">
<div class="card-header" role="tab" id="headingOne">
<div class="mb-0">
<a data-toggle="collapse" :href="computedId">
Piezas asociadas {{nombre_motor}} <i class="fa fa-caret-down" aria-hidden="true"></i>
</a>
<button #click="addPieza(id_motor)" class="btn pull-right" title="AƱadir pieza nueva al motor"><i class="fa fa-plus text-info" aria-hidden="true"></i></button>
</div>
</div>
<div :id="id_motor" class="collapse" role="tabpanel" aria-labelledby="headingOne" data-parent="#accordion">
<div class="card-body">
<ul class="list-group">
<li class="list-group-item" v-for="pieza in piezas_motor">
<span class="badge badge-secondary">{{nombre_motor}}</span> {{pieza.pieza}}
<button class="btn btn-sm btn-danger pull-right"><i class="fa fa-trash" aria-hidden="true"></i></button>
</li>
</ul>
</div>
</div>
</div>
</div>
</div>
</template>
<script>
export default {
props: ['motor'],
data: function () {
return {
nombre_motor: this.motor.motor,
id_motor: this.motor.id,
id_color: this.motor.color.id,
piezas_motor: this.motor.piezas,
}
},
methods: {
show_modal_colores: function(id){
let $engine = $('#engine-colors');
$engine.data('motor-id', id);
$engine.find('div.color').removeClass('active');
$engine.find('div[data-id="'+this.activeColor+'"]').addClass('active');
$engine.modal('show');
},
addPieza(id) {
let $form = $('#form-pieza');
$form.data('motor-id', id);
$form.modal('show');
}
},
computed: {
computedId: function () {
return '#'+ this.id_motor;
},
backgroundColor: function () {
return 'background-color: '+ this.motor.color.codigo;
},
activeColor: function () {
return this.motor.color.id;
}
},
}
And here the parent code (root component):
Vue.component('card-motor', require('./components/CardMotor.vue'));
var app = new Vue ({
el: '#app',
data: {
dataMotores: [],
dataPuestos: [],
background_style: {
'background-color': ''
}
},
methods: {
makeActiveColor: function(e) {
$(e.currentTarget).closest('.modal-body').find('div.color').removeClass('active');
$(e.currentTarget).closest('div.color').addClass('active');
},
changeColor: function(e) {
let vm = this;
let id=$(e.currentTarget).closest('div.modal-content').find('.active').data('id');
let motor_id = $(e.currentTarget).closest('#engine-colors').data('motor-id');
axios.post('/admin/motores/change-color', {idmotor:motor_id, idcolor: id})
.then(response=>{
this.getData();
$('#engine-colors').modal('hide');
});
},
getData: function(){
axios.get('/admin/motores/api/data')
.then(response => {
this.dataMotores = response.data.motores;
this.dataPuestos = response.data.puestos;
})
.catch();
}
},
computed: {
chunkDataMotores() {
return _.chunk(this.dataMotores, 2);
}
},
created: function() {
this.getData();
}
});
Data returned from the axios call to the server are arrays of objects (getData method). Computed properties updates properly on the component, but not the data property.
You are making copies of your props, so the component renders, make your copies inside data(), but data() is called once, so when the parent component updates the child does not update.
data: function () {
return {
nombre_motor: this.motor.motor,
id_motor: this.motor.id,
id_color: this.motor.color.id,
piezas_motor: this.motor.piezas,
}
},
You can use motors prop directly, like:
<div class="card-header" :style="backgroundColor">
<h4 class="text-center">
{{ motor.motor }}
<button class="btn btn-dark btn-sm pull-right"
:data-motor-id="motor.id"
#click="show_modal_colores(motor.id)">
Color motor
</button>
</h4>
</div>
You need to pass value of dataMotores in components
<card-motor :motor="dataMotores"></card-motor>