Let's say I have this list of objects in Vue.JS
data () {
return{
examples: [
{
exampleID: 5,
exampleText: 'foo'
},
{
exampleID: 3,
exampleText: 'bar'
}
]
}
}
Now let's say I want to display the object with the exampleID of 3 in an element i created before
<Task
v-for="example in examples"
:key="example.exampleID"
:example="example"
/>
I want to display everything, that is in the object (the ID and the text)
Task component :
<template>
<div class="exercise">
<div class="exercise-id">
<h1>ID NUMBER: {{ example.exampleID }}</h1>
</div>
<div class="exercise-task">
<h2>{{ example.exampleText}}</h2>
</div>
</div>
</template>
<script>
export default {
name: 'Task',
props: ['example']
}
</script>
You shouldn't use v-if and v-for in the same element, in this case i suggest to use a computed property that only return the desired example :
data () {
return{
examples: [
{
exampleID: 5,
exampleText: 'foo'
},
{
exampleID: 3,
exampleText: 'bar'
}
]
}
},
computed:{
myExample(){
return this.examples.find(ex=>ex.exampleID===3)
}
}
then render it like :
<Task :example="myExample"/>
Another efficient way of doing it without v-for is
data () {
return{
examples: [
{
exampleID: 5,
exampleText: 'foo'
},
{
exampleID: 3,
exampleText: 'bar'
}
],
id: 3
}
},
computed:{
myExample(){
return id => this.examples.find(ex=>ex.exampleID===id)
}
}
rendering part will be like
<Task :example="myExample(id)"/>
In this way you no need to hardcode the value as 3 in the computed property.
Related
I am trying to create a v-for that shows a list of exercises containing several sets. I have created a loop with a row for each set underneath each exercise.
my data looks like this.
const exercises = [
{ id: 1, name: exercise1, sets: 3 },
{ id:2, name: exercise2, sets: 2 }
{ id:3, name: exercise3, sets: 4 }
]
And my component looks something like this:
<template v-for="exercise in exercises" :key="exercise.id">
<span> {{ exercise.name }} </span>
<template v-for="set in exercise.sets" :key="set">
<span #click="completeSet()"> {{ set }} </span>
</template>
</template>
Now I want to be able to mark each set as completed by setting the value on each set to either true or false through a click event. But I am not sure about how to do this since each set doesn't have a property to set a value because it's looping through a number.
What would be the right approach to this problem?
First and foremost, you can't loop through a number. To be able to loop the sets, you'd have to
<template v-for="let set = 0; set < exercise.sets; set++" :key="set">
<span #click="completeSet()"> {{ set }} </span>
</template>
However, setting a property on a number is equally impossible. You have to prepare your data to be able to make that adjustment:
const exercises = [
{ id: 1, name: 'exercise1', sets: 3 },
{ id: 2, name: 'exercise2', sets: 2 } ,
{ id: 3, name: 'exercise3', sets: 4 }
].map(exercise => ({
id: exercise.id,
name: exercise.name,
sets: Array.from(
{ length: exercise.sets },
() => ({ completed: false })
),
}))
You can create array with finished sets and compare it (try the snippet pls):
new Vue({
el: "#demo",
data() {
return {
exercises: [{ id: 1, name: 'exercise1', sets: 3 }, { id: 2, name: 'exercise2', sets: 2 }, { id: 3, name: 'exercise3', sets: 4 }],
finishedSets: []
}
},
computed: {
checkAll() {
return this.exercises.reduce((acc, curr) => acc + curr.sets, 0) === this.finishedSets.length
}
},
methods: {
compareObjects(o1, o2) {
return Object.entries(o1).sort().toString() !== Object.entries(o2).sort().toString()
},
findObject(id, set) {
return this.finishedSets.find(f => f.id === id && f.set === set)
},
completeSet(id, set) {
this.findObject(id, set) ?
this.finishedSets = this.finishedSets.filter(f => {return this.compareObjects(f, this.findObject(id, set))}) :
this.finishedSets.push({id, set})
},
isFinished(id, set) {
return this.findObject(id, set) ? true : false
},
}
})
.set {
width: 70px;
cursor: pointer;
}
.finished {
background-color: seagreen;
}
.finished__not {
background-color: tomato;
}
<script src="https://cdnjs.cloudflare.com/ajax/libs/vue/2.5.17/vue.js"></script>
<div id="demo">
<div v-for="exercise in exercises" :key="exercise.id">
<span> {{ exercise.name }} </span>
<div v-for="set in exercise.sets" :key="set">
<div #click="completeSet(exercise.id, set)" class="set" :class="isFinished(exercise.id, set) ? 'finished' : 'finished__not'"> {{ set }} <span>
<span v-if="isFinished(exercise.id, set)">finished</div>
</div>
</div>
<button v-if="checkAll">submit</button>
<p>{{finishedSets}}</p>
</div>
HelloWorld.vue
<template>
<div>
<div v-for="box in boxes" :key="box.sname">
<BaseAccordian>
<template v-slot:title>{{ box.sname }}</template>
<template v-slot:content>
<div v-for="paint in paints" :key="paint.tname" class="line">
<List :content="matchingdata" :sname="box.sname" />
</div>
</template>
</BaseAccordian>
</div>
</div>
</template>
<script>
import BaseAccordian from "./BaseAccordian.vue";
import List from "./List.vue";
export default {
name: "HelloWorld",
components: {
BaseAccordian,
List,
},
data() {
return {
boxes: [
{
sname: "apple",
},
{
sname: "bananna",
},
{
sname: "grapes",
},
{
sname: "choc",
},
],
paints: [
{
tname: "a",
},
{
tname: "b",
},
{
tname: "c",
},
{
tname: "d",
},
{
tname: "e",
},
],
matchingdata: [
{
matchid: "1",
OverallStatus: "ok",
sname: "choc",
},
{
matchid: "2",
OverallStatus: "notok",
sname: "grapes",
},
],
};
},
};
</script>
BaseAccordion.vue
<template>
<div class="wrapper">
<div class="accordion">
<input type="checkbox" #click="toggleItem" />
<h2 class="title">
<slot name="title"></slot>
</h2>
</div>
<div v-show="show" class="content">
<slot name="content"></slot>
</div>
</div>
</template>
<script>
export default {
components: {},
data: function () {
return {
show: false,
};
},
methods: {
toggleItem: function () {
this.show = !this.show;
},
},
};
</script>
List.vue
<template>
<div class="">
<div
v-for="match in matchingData"
:key="match.matchid"
:class="{
green: match.OverallStatus === 'ok',
red: match.OverallStatus === 'notok',
}"
>
{{ match.OverallStatus }}
</div>
</div>
</template>
<script>
export default {
components: {},
props: {
content: {
type: Array,
required: true,
},
sname: {
type: String,
required: true,
},
},
data: function () {
return {};
},
methods: {},
computed: {
matchingData() {
return this.content.filter((a) => {
if (a.sname === this.sname) {
return true;
} else {
return false;
}
});
},
},
};
</script>
<style scoped>
</style>
I three arrays called matchingdata,boxes,paints array based on this three arrays, i am trying to filter the array.(nested v-for)
Now, I want to iterate the matchingdata array by comparing it with sname in boxes array. and Common value between matchingdata and boxes array is ""sname""
I tried above logic, and struck with computed property.
Expected Output:-
In List.vue component , i have
{{ match.OverallStatus }} where that field , i want to show,(from the matchingdata array) when user clicked on checkbox.
Taking the ""sname"" the common value from the matchingdata array and the boxes array
code:- https://codesandbox.io/s/damp-pine-27s2kn?file=/src/components/List.vue
As you're passing the sname property as a string via a prop to your List.vue component, you'll just need to use that string in your filter function.
matchingData() {
return this.content.filter((a) => a.sname === this.sname)
},
I've tried this in your codesandbox link and it is giving some output - but I'm not clear enough on what you're trying to achieve to know if this is the intended outcome.
Just incase you're not aware the 'filter' function returns a new array. It's not going to return a 'true/false' which I feel you may be trying to do.
https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Array/filter
I have this array:
data() {
return {
landingInfo: null,
slides: [
{
title: `this`,
},
{
title: "that",
},
{
title: "those",
},
],
};
},
Which is being displayed this way:
<div
class="slide"
v-for="(slide, index) in slides"
:key="index",
}"
>
<div>
<h1 class="text-bold">{{ slide.title }}</h1>
</div>
The problem is that I'm fetching info from and api and once I try to do:
slides: [
{
title: {{ landingInfo.data.subtitle }},
},
{
title: {{ landingInfo.data.subtitle2 }},
},
{
title: {{ landingInfo.data.subtitle3 }},
},
],
Everything explodes, I am new in vue using Nuxt.js and I cannot find any solution in how to achieve that.
Can someone show me how to include the fetched info inside the array property?
PD: I already tried using "{{thefetchedinfo}}" but it takes it literally that way and displays "{{thefetchedinfo}}"
The OP doesn't provide much info on the fetch, like when it is performed or what the returned data looks like, but the common pattern goes like this...
// <template> as in the OP, then...
data() {
return {
landingInfo: null,
slides: [], // empty before the fetch
};
},
mounted () {
fetchFromTheAPI().then(landingInfo => {
// More commonly, you'd map over the returned data to form slides,
// or, trying to match the OP...
this.slides = [
{ title: landingInfo.data.subtitle },
{ title: landingInfo.data.subtitle2 }, // ... and so on
]
});
},
I'm trying to have a component representing a shopping item.
I'll have one of this component for every item in my shopping list.
I don't know how to update the parent data (the shopping list) when the child is edited (the shopping item)
Shopping List
<template>
<div id="app">
<shopping-item
v-for="(item, index) in shoppingList"
:key="index"
:propsName="item.name"
:propsQuantity="item.quantity"
#shoppingItemEdited="handleEdit"
></shopping-item>
</div>
</template>
<script>
import ShoppingItem from "./components/ShoppingItem.vue";
export default {
name: "App",
components: {
ShoppingItem,
},
data() {
return {
shoppingList: [
{ name: "apple", quantity: 8 },
{ name: "banana", quantity: 3 },
{ name: "kiwi", quantity: 7 },
{ name: "peach", quantity: 5 },
],
};
},
methods: {
handleEdit(itemEdited) {
// How to get the index of the shopping-item that has been updated ?
// shoppingList[???] = itemEdited
console.log(itemEdited);
// => {name: "white peach", quantity: "6"}
},
},
};
</script>
Shopping Item
<template>
<div>
<input v-model="name" placeholder="ex: banana" #change="updateParent" />
<input
v-model="quantity"
type="number"
placeholder="ex: 3"
#change="updateParent"
/>
</div>
</template>
<script>
export default {
data() {
return {
name: "",
quantity: null,
};
},
props: {
propsName: String,
propsQuantity: Number,
},
created() {
this.name = this.propsName;
this.quantity = this.propsQuantity;
},
methods: {
updateParent() {
this.$emit("shoppingItemEdited", {
name: this.name,
quantity: this.quantity,
});
},
},
};
</script>
So I have few questions:
How can I know witch component emited the event 'shoppingItemEdited' ? If I knew it, I could find out which shoppingList item I should update.
I red I should not update props in the child, so I create data based on props, is that a standard way of doing that ?
this.name = this.propsName;
this.quantity = this.propsQuantity;
Just pass an index to a handler: #shoppingItemEdited="handleEdit(index, $event)"
No it's not "standard" - created hook is called only once when component is created, so if value of prop changes later (from parent), data will not update. It's probably not a problem in your case but usually its better to use computed:
computed: {
name: {
get() { return this.propsName },
set(value) {
this.$emit("shoppingItemEdited", {
name: value,
quantity: this.quantity,
});
}
}
}
...handle event in parent and the change will propagate (by props) to a child
How do you access the computed properties of components in Vue from the parent?
In this example, I have a cart with item components and I want to compute and display the sum of the cart items:
cart.js
var vm = new Vue({
el: '#cart',
components: {
cartItem: require('./components/cart-item.js'),
},
data: {
items: [
{ name: 'apple', qty: 5, price: 5.00 },
{ name: 'orange', qty: 7, price; 6.00 },
],
},
computed: {
// I want to do something like this and access lineTotal from cart
cartTotal: function() {
return this.items.reduce(function(prev,curr) {
return prev + curr.lineTotal;
}, 0)
}
}
});
cart-item.js
module.exports = {
template: require('./cart-item.template.html'),
props: ['fruit'],
computed: {
lineTotal: function() {
return this.fruit.price * this.fruit.qty;
}
},
};
main html
<li v-for="item in items" is="cart-item" :fruit="item">
...
#{{ cartTotal }}
How do I access the lineTotal properties of each cart-item to use in summing cartTotal?
Note that I do not want to redo the calculations done in lineTotal but instead use the computed properties directly.
You have to name the children, for example by means of the v-ref directive. Then from the parent you resolve the children properties with this.$refs.mychild.myproperty