v-for with dynamic keys - vue.js

Very new to Vuejs 2. Have a question on how to enumerate through a dynamic set of data that has a dynamic key? Take this data for instance (this is from a 3rd party -- so unable to change data -- and shortened for readability):
{
"143": {
"account_id": 1,
"name": "Account 1",
"groups": [
{
"1610": {
"name": "Group 1610",
"meetings": [
{
"20170816": [
{
"id": 10755,
"name": "Untitled"
}
]
}
]
}
}
]
}
}
Then I have a .vue file that has a template that does this:
<div v-for="(account, accountKey) in accounts">
<div>{{ account.name }} ({{ accountKey }})</div>
<div v-for="(group, groupKey) in groups">
<div>{{ group.name }} ({{ groupKey }})</div>
<div v-for="(meeting, meetingKey) in meetings">
<div>{{ meeting.name }} ({{ meetingKey }})</div>
</div>
</div>
</div>
This doesn't render anything. There are several things I need to here, but not sure how to accomplish in Vuejs.
Need to be able to pull the key (as it's the identifier) for each of the records.
Need to be able to access the individual data on record, of course.
Anyone come across something similar that can help with?
Thanks!

That might be one of the worst data structures I've ever seen.
Here is a template that works as I think you intend.
<div v-for="(account, accountKey) in accounts">
<div>{{ account.name }} ({{ accountKey }})</div>
<div v-for="group in account.groups">
<div v-for="grp, grpKey in group">
<div>{{ grp.name }} ({{ grpKey }})</div>
<div v-for="(meeting, meetingKey) in grp.meetings">
<div v-for="mtg, mtgKey in meeting">
<div v-for="m in mtg">{{ m.name }} ({{ mtgKey }})</div>
</div>
</div>
</div>
</div>
</div>
Groups is an array of objects that have their own set of keys so you need to iterate over that, and then iterate again over each object inside the group.
Meetings is the same kind of thing, an array of objects with their own keys, but it doubles down and each of the key values is an array that... has to be iterated over again.
console.clear()
new Vue({
el: "#app",
data:{
accounts: {
"143": {
"account_id": 1,
"name": "Account 1",
"groups": [
{
"1610": {
"name": "Group 1610",
"meetings": [
{
"20170816": [
{
"id": 10755,
"name": "Untitled"
}
]
}
]
}
}
]
}
}
}
})
<script src="https://unpkg.com/vue#2.4.2"></script>
<div id="app">
<div v-for="(account, accountKey) in accounts">
<div>{{ account.name }} ({{ accountKey }})</div>
<div v-for="group in account.groups">
<div v-for="grp, grpKey in group">
<div>{{ grp.name }} ({{ grpKey }})</div>
<div v-for="(meeting, meetingKey) in grp.meetings">
<div v-for="mtg, mtgKey in meeting">
<div v-for="m in mtg">{{ m.name }} ({{ mtgKey }})</div>
</div>
</div>
</div>
</div>
</div>
</div>
It would probably be worthwhile transforming that data into a sane data structure with a computed value and iterating over the computed.

Related

Vue v-model/v-for doesn't update on mount, but after first manual change

I have a dropdown list "functions" that is filled with database entries and a dropdown list with 2 hardcoded entries. When the vue website is opened the dropdown list remains empty but as soon as I change the value of the other dropdown field the desired data from the database is available.
I'm a bit confused because I expected that adding "retrieveFunctions()" into the mounted() function would trigger the v-for, and even more confused that changing something in another select field suddenly triggers it.
The HTML code:
<template>
<div class="submit-form">
<div v-if="!submitted">
<div class="row">
<div class="col-sm-12">
<p><a style="width:500px" class="btn btn-info" data-toggle="collapse" href="#generalInformation" role="button" aria-expanded="true" >
General Information</a></p>
<div class="collaps show" id="generalInformation">
<!-- NAME -->
<div class="form-group">
<input placeholder="Name" type="text" class="form-control"
id="name" required v-model="component.name" name="name">
</div>
<!-- DOMAIN -->
<div class="input-group mb-3">
<div class="input-group-prepend">
<label style="width:100px" class="input-group-text" for="inputGroupDomain">Domain</label>
</div>
<select v-model="component.domain"
class="custom-select"
id="inputGroupDomain"
>
<option value="Power System">Power System</option>
<option value="ICT">ICT</option>
</select>
</div>
<!-- FUNCTION -->
<div class="input-group mb-3">
<div class="input-group-prepend">
<label style="width:100px" class="input-group-text" for="inputGroupFunction">Functions</label>
</div>
<select v-model="_function" class="custom-select" id="inputGroupFunction">
<option :class="{ active: index == currentIndex }"
v-for="(_function, index) in functions"
:key="index"
value= _function.name>
{{ _function.name }}
</option>
</select>
</div>
</div>
<p>
<button #click="saveComponent" class="btn btn-success">Add Component</button>
</p>
</div>
</div>
</div>
<div v-else>
<h4>Component was added succesfully!</h4>
<button class="btn btn-success" #click="newComponent">Proceed</button>
</div>
The script part:
<script>
import FunctionDataService from "../services/FunctionDataService";
export default {
name: "add-component",
data() {
return {
component: {
id: null,
name: "",
type: "",
domain: "",
},
submitted: false
};
},
methods: {
retrieveFunctions() {
FunctionDataService.getAll()
.then(response => {
this.functions = response.data;
console.log(response.data);
})
.catch(e => {
console.log(e);
});
},
refreshList() {
this.retrieveFunctions();
},
},
mounted() {
this.retrieveFunctions();
}
};
</script>
refreshList() {
this.retrieveFunctions();
},
},
mounted() {
this.retrieveFunctions();
}
};
</script>
State in the beginning: Dropdown list empty
State after selecting something in the upper dropdown list: Database entries are visible and correct
You need to initiate all responsive properties on the data return object with either a value (empty string, array, object, etc) or null. Currently it's missing the _function attribute used in the select v-model and the functions array used in the v-for. You can try to change the data to the following:
data() {
return {
_function: "",
functions: [],
component: {
id: null,
name: "",
type: "",
domain: "",
},
submitted: false
};
},

How can I add a task to a list in my Vue 2 to-do app?

I am trying to add a task to a tasklist in Vue based on the input and add task button, but I keep getting the error "taskList is not defined". Does anybody see how to fix this problem? The code is as following:
<template>
<div id="input">
<form>
<input v-model="task.name">
<button v-on:click="addTask" v-bind:value="task.name">+</button>
</form>
<ol>
<div v-for="task in taskList" :key="task.id">
{{ task.name }}
<div v-if="task.completed">
<h2> Done </h2>
</div>
<div v-else>
<h2> Not done</h2>
</div>
</div>
</ol>
</div>
</template>
<script>
export default {
name: 'AddTask',
data: function() {
return {
taskList: [
{
name: 'task', completed: false, id: 3
}
] }
},
methods: {
addTask: function (task) {
taskList.push(task);
alert('test');
}
}
}
</script>
Ps. any other Vue tips are welcome as well.
You need to separate out your taskList and the current task you're adding, decouple it as a new object, then add it to your taskList array.
When referring to items in your data object you need to use the this keyword – e.g this.taskList rather than taskList:
new Vue({
el: "#app",
data: {
id:1,
taskList: [],
currentTask:{
completed:false,
name:'',
id:this.id
}
},
methods: {
addTask: function() {
let newTask = {
completed:this.currentTask.completed,
name:this.currentTask.name,
id:this.currentTask.id
}
this.taskList.push(newTask);
this.id++;
//alert('test');
}
}
})
<script src="https://cdnjs.cloudflare.com/ajax/libs/vue/2.5.17/vue.js"></script>
<div id="app">
<div id="input">
<ol>
<li v-for="task in taskList" :key="task.id">
{{ task.name }}
<input type="checkbox"
:checked="task.completed"
#change="task.completed = !task.completed">
<span v-if="task.completed">
Done
</span>
<span v-else>
Not Done
</span>
</li>
</ol>
<input type="text" v-model="currentTask.name">
<button v-on:click="addTask">+</button>
</div>
</div>
From what I see in your template you use tasklist but you define it as taskList You will want to make sure your names are in the same case. Usually you'll see camelCase in vue, but other popular ones are snake_case and PascalCase

Array of Dynamic Dependent Select Box in Vue.js

I have an array of Depend select box which contains Universities and courses. Each university has its own course. and I have built the course dropdown which depends on the university. I can successfully get university course from server request but the problem is when I change the select university it's changing all course fields. How I can get rid of the problem please give me some ideas. Thanks
<template>
<form #submit.prevent="handleSubmit">
<div class="col col-md-12">
<div v-for="(interest, index) in interests" :key="index" class="row">
<div class="col col-md-6">
<div class="form-group mb-4">
<label for="select-ins">Interested Universities </label>
<select
v-model="interest.institute_id"
class="form-control"
#change="onChangeUniversity($event)"
>
<option disabled value="">Select a University</option>
<option
v-for="institute in institutes"
:key="institute.id"
:value="institute.id"
>
{{ institute.institute_name }}
</option>
</select>
</div>
</div>
<div class="col col-md-6">
<div class="form-group mb-4">
<label>Interested Course</label>
<select
v-model="interest.course_id"
class="form-control"
#change="onChangeCourse($event)"
>
<option disabled value="">Select a Course</option>
<option
v-for="course in courses"
:key="course.id"
:value="course.id"
>
{{ course.course_name }}
</option>
</select>
</div>
</div>
<div class="col col-md-12 text-right">
<div class="row ml-4">
<div v-show="index == interests.length - 1">
<button
class="btn btn-warning mb-2 mr-2 btn-rounded"
#click.prevent="add"
>
Add
</button>
</div>
<div v-show="index || (!index && interests.length > 1)">
<button
class="btn btn-danger mb-2 mr-2 btn-rounded"
#click.prevent="remove"
>
Remove
</button>
</div>
</div>
</div>
</div>
</div>
</form>
</template>
<script>
export default {
data() {
return {
institutes: [],
courses: [],
interests: [
{
institute_id: "",
course_id: "",
},
],
};
},
mounted() {
axios.get("/institues").then((res) => {
this.institutes = res.data;
});
},
methods: {
onChangeUniversity(event) {
let universityId = event.target.value;
axios.get(`/institute-course/${universityId}`).then((res) => {
this.courses = res.data;
});
},
add() {
this.interests.push({
institute_id: "",
course_id: "",
});
},
remove(index) {
this.interests.splice(index, 1);
},
},
};
</script>
check screenshot
http://prntscr.com/115mkn5
lets start at your mounted hook.
you call for a API to receive all available institutes. so far so good. each institute got is own ID, this is important for later, lets keep that in mind.
now your using a function which will then call on a "change" event, like onChangeUniversity this is a good way on preventing to overload data in a page, nice idea just to fetch data only when they are needed.
then comes the tricky part which makes it difficult for you and everyone else reading your code.
you have this courses array in your data which normally belongs to the related institute. this array should not be handled as a second array apart from institutes, it should be a child of it.
like check this data structur:
institutes: [
{
institute_name: "WhatEver1",
id: 0,
courses: [{ course: 1 }, { course: 2 }, { course: 3 }],
}
]
instead of this:
institutes: [
{
institute_name: "WhatEver1",
id: 0,
},
],
courses: [{ course: 1 }, { course: 2 }, { course: 3 }],
the first option above is a good nested way to display your data as loop inside a loop.
which means you have to push your courses inside your institute of choice with the belonged id.
your onChangeUniversity function should than do something like this:
onChangeUniversity(event) {
let universityId = event.target.value;
axios.get(`/institute-course/${universityId}`).then((res) => {
const foundedId = this.institutes.findIndex(institute => institute.id === universityId)
this.institutes[foundedId].courses = res.data
});
},
after that its much easier to iterate over and display the data inside the options. and i am sure you will not have that issue anymore.
just try it like that first and give feedback.
Update
<div class="form-group mb-4">
<label>Interested Course</label>
<select
v-model="interest.course_id"
v-if="institute.courses.length !== 0" <-------HERE
class="form-control"
#change="onChangeCourse($event)"
>
<option disabled value="">Select a Course</option>
<option
v-for="course in institute.courses"
:key="course.id"
:value="course.id"
>
{{ course.course_name }}
</option>
</select>
</div>
you need a render condition to stop your courses loop from being iterated when there is no data inside.
also make sure you await till the fetching of courses is completed.
async onChangeUniversity(event) {
let universityId = event.target.value;
await axios.get(`/institute-course/${universityId}`).then((res) => {
this.courses = res.data;
});
},
and also in your mounted hook
async mounted() {
await axios.get("/institues").then((res) => {
this.institutes = res.data;
});
},
if you still struggle please give me a CodeSandbox of your current code.

Populate text value when option selected from dropdown in vue

I have a vue app and new to vue. I have a dropdown which is populated via an axios endpoint. This returns 2 items. What I'm trying to do is, if 'APC' is selected, then populate a text value with an attribute value returned in my array but this is where I may be overthinking.
My thinking is that I need to iterate over the items again but if a condition is met display the value.
Below is my whole page code
<template>
<div>
<div class="form-group row">
<label class="col-sm-3 col-form-label" for="courierList">Courier <span class="text-danger">*</span></label>
<div class="col-sm-7 shipping-options">
<select id="courierList" class="form-control" v-model="selectedCourier">
<option value='courierDefault'>Please select a courier</option>
<option :value="courier.name.toLowerCase()" v-for="(courier, index) in couriers" :key="courier.index">
{{ courier.name }}
</option>
</select>
</div>
</div>
<span v-if="selectedCourier != 'courierDefault'">
<div class="form-group row">
<b class="col-sm-3" for="cutOff">Order cut-off</b>
<div class="col-sm-7 shipping-options" v-for="(cutOff, index) in couriers" :key="cutOff.index">
{{ cutOff.cut_off }}
</div>
</div>
</span>
</div>
</template>
<script>
export default {
name: 'CourierSelect',
data() {
return {
couriers: [],
selectedCourier: 'courierDefault'
}
},
mounted() {
this.fetchCouriers();
},
methods: {
fetchCouriers() {
axios.get('/CHANGED_FOR_SECURITY')
.then((response) => {
this.couriers = response.data.couriers;
console.log('axios_couriers', this.couriers)
})
.catch((error) => {
VueEvent.$emit('show-error-modal', 'cartFethchCouriers');
console.log(error);
});
}
}
}
</script>
My console.log for 'axios_couriers' gives
Then when I select 'APC' my page displays as
But what I need is for the 'cut_off' value (displayed in the console screenshot) for the 'APC' Array object to display only. The value should be 16:30
Is there a way to do this as a Computed prop or something?
As you suggested a computed should indeed work.
One way would be:
currentCutOff() {
return this.couriers.find(c => c.name == this.selectedCourier).cut_off;
}
This tries to find the courier from your array which equals the name of the currently selectedCourier.
There is a much simplier solution with vuejs data binding.
Check this code:
const vm = new Vue({
el: '#app',
data() {
return {
items: [{
id: 1,
name: 'AAA',
time: '14:00'
},
{
id: 2,
name: 'BBB',
time: '18:00'
}
],
selected: null
}
}
})
<script src="https://unpkg.com/vue#2.6.10/dist/vue.min.js"></script>
<div id="app">
<select v-model="selected">
<option disabled value="null">Please select one</option>
<option v-for="item in items" v-bind:value="item">
{{ item.name }}
</option>
</select>
<div>Selected: {{ selected? selected.time : 'nothing selected' }}</div>
</div>

How to isolate component in Vue.js

I have a problem at the beginning of my Vue education.
I made a small app. How can I isolate component?
After clicking on the arrow I'd like to open only one section of information.
Here's the code and live demo:
https://lemonwm.github.io/app_vue/
https://github.com/lemonWM/app_vue
If you plan to iterate through your recipes, you can add a property expanded: false for each recipe and toggle this one (instead of a global data property):
<div class="element-menu" v-for="recipe in recipes">
<div class="main-element">
<h2>{{ recipe.title }}</h2>
<div>
<button v-on:click='recipe.expanded = !recipe.expanded'><img src="img/arrow_06.png" alt=""></button>
</div>
</div>
<div class="desribe-element">
<div v-if='recipe.expanded'>
<div class="recipe-ingredience-left">
<h3>Składniki</h3>
<p v-for="ingredient in recipe.ingredients">{{ ingredient }}</p>
</div>
<div class="recipe-ingredience-right">
<h3>Przygotowanie</h3>
<p>{{ recipe.description }}</p>
</div>
</div>
</div>
</div>
data() {
return {
recipes: [
{
title: "Spaghetti",
ingredients: [
"Podwójna porcja makaronu",
"500g sera białego tłustego",
"2 łyżeczki soli (lub do smaku)",
"1/2 łyżeczki zmielonego pieprzu"
],
description: "Lorem...",
expanded: false //<-- here
},
{
title: "Carbonara",
ingredients: [
"...",
],
description: "..",
expanded: false,
},
]
}
}