mount lifecycle hook not triggered in Vue js 2 - vue.js

I am new to Vue and was struggling with this basic code in Vue js 2.
I want to call a function on load of the component. So i am using mounted life cycle hook. But that is not getting triggered.
<template>
<div>--- {{ res }} ---</div>
</template>
<script>
export default {
name: "OrderChargeDetailsContainer",
data() {
return {
res: "It should change",
};
},
mounted() {
alert('alert');
this.res = "Updated data";
},
};
</script>
Any help is appreciated.

It should work as mentioned in the following running code :
new Vue({
el:"#app",
name: "OrderChargeDetailsContainer",
data() {
return {
res: "It should change",
};
},
mounted() {
alert('alert');
this.res = "Updated data";
},
})
<script src="https://cdnjs.cloudflare.com/ajax/libs/vue/2.5.17/vue.js"></script>
<div id="app">
<div>--- {{ res }} ---</div>
</div>

Related

vue.js – get new data information

I'm building a chrome extension using vue.js. In one of my vue components I get tab informations of the current tab and wanna display this information in my template. This is my code:
<template>
<div>
<p>{{ tab.url }}</p>
</div>
</template>
<script>
export default {
data() {
return {
tab: {},
};
},
created: function() {
chrome.tabs.query({ active: true, windowId: chrome.windows.WINDOW_ID_CURRENT }, function(tabs) {
this.tab = tabs[0];
});
},
};
</script>
The Problem is, that the template gets the data before it's filled through the function. What is the best solution for this problem, when the tab data doesn't change after it is set once.
Do I have to use the watched property, although the data is only changed once?
// EDITED:
I've implemented the solution, but it still doesn't work. Here is my code:
<template>
<div>
<div v-if="tabInfo">
<p>set time limit for:</p>
<p>{{ tabInfo.url }}</p>
</div>
<div v-else> loading... </div>
</div>
</template>
<script>
export default {
data() {
return {
tabInfo: null,
};
},
mounted() {
this.getData();
},
methods: {
getData() {
chrome.tabs.query({ active: true, windowId: chrome.windows.WINDOW_ID_CURRENT }, function(tabs) {
console.log(tabs[0]);
this.tabInfo = tabs[0];
});
},
},
};
</script>
The console.log statement in my getData function writes the correct object in the console. But the template only shows the else case (loading...).
// EDIT EDIT
Found the error: I used 'this' in the callback function to reference my data but the context of this inside the callback function is an other one.
So the solution is to use
let self = this;
before the callback function and reference the data with
self.tab
You could initialize tab to null (instead of {}) and use v-if="tabs" in your template, similar to this:
// template
<template>
<div v-if="tab">
{{ tab.label }}
<p>{{ tab.body }}</p>
</div>
</template>
// script
data() {
return {
tab: null,
}
}
new Vue({
el: '#app',
data() {
return {
tab: null,
}
},
mounted() {
this.getData();
},
methods: {
getData() {
fetch('https://reqres.in/api/users/2?delay=1')
.then(resp => resp.json())
.then(user => this.tab = user.data)
.catch(err => console.error(err));
}
}
})
<script src="https://unpkg.com/vue#2.5.17"></script>
<div id="app">
<div v-if="tab">
<img :src="tab.avatar" width="200">
<p>{{tab.first_name}} {{tab.last_name}}</p>
</div>
<div v-else>Loading...</div>
</div>

How to build a bridge of events between different components in Vue?

I need to solve it
1) click mainMidLeft component
2) after clicked, to move slideLeftTop component
http://joxi.ru/ZrJBvERH1JVa8r
The problem I dont quite understand how to do this in right way..
Is it okay to create in mainMidLeft a method where I will do somethik like this:
move: () => {
document.querySelector(`.slideLeftTop`).style.position .....
}
The best practice is to use Vuex State manager with computed methods (getters) and watchers
I have made a working example for you on jsfiddle.
https://jsfiddle.net/n4e_m16/wujafg5e/4/
For more info on how vuex works please go to Here
Please let me know if you need more help :)
const store = new Vuex.Store({
state: {
mainMidLeftState: false,
},
getters: {
mainMidLeftState: state => state.mainMidLeftState,
},
mutations: {
toggleMainMidLeft: (state, payload) => {
state.mainMidLeftState = !state.mainMidLeftState
},
},
})
Vue.component('main-mid-left', {
data() {
return {
}
},
computed: {
mainMidLeftState() {
return this.$store.state.mainMidLeftState
},
},
methods: {
toggleMainMidLeft() {
this.$store.commit('toggleMainMidLeft')
// alert(this.mainMidLeftState)
},
}
})
Vue.component('slide-left-top', {
data() {
return {
}
},
computed: {
mainMidLeftState() {
return this.$store.state.mainMidLeftState
},
},
watch: {
mainMidLeftState: function(val) {
alert("YES, computed property changed and alert have been triggered by watcher in slide top left component")
}
},
methods: {
}
})
const app = new Vue({
el: '#app',
store,
})
div {
color: black;
}
<script src="https://unpkg.com/vue/dist/vue.js"></script>
<script src="https://unpkg.com/vuex#3.0.1/dist/vuex.js"></script>
<div id="app">
<!-- inlining the template to make things easier to read - all of below is held on the component not the root -->
<main-mid-left inline-template>
<div>
<h4>
main mid left
</h4>
<button v-on:click="toggleMainMidLeft()">toggle Main Mid Left State</button>
<div v-show="mainMidLeftState == true">State is true</div>
<div v-show="mainMidLeftState == false">State is false</div>
</div>
</main-mid-left>
<slide-left-top inline-template>
<div>
<h4>
slide left top
</h4>
<div v-show="mainMidLeftState == true">State is true</div>
<div v-show="mainMidLeftState == false">State is false</div>
</div>
</slide-left-top>
</div>
If you don't want to use vuex, you can create a new Vue instance as an event bus (I believe this is mentioned somewhere in the Vue tutorial):
const EventBus = new Vue()
Import EventBus to where you need it and you can send an event by:
EventBus.$emit('event-name', data)
And add the following script in created() of your receiver component:
EventBus.$on('event-name', ($event) => {
// Do something
})
I hope this helps |´・ω・)ノ

vuejs data doesn't change when property change

I am very new to Vuejs so although I can probably devise a solution myself by using a watcher or perhaps a lifecycle hook I would like to understand why the following does not work and what should be done instead.
The problem is that the mutated local data doesn't update whenever the component consumer changes the property cellContent. The parent owns cellContent so using the property directly is a no-no (Vue seems to agree).
<template>
<textarea
v-model="mutableCellContent"
#keyup.ctrl.enter="$emit('value-submit', mutableCellContent)"
#keyup.esc="$emit('cancel')">
</textarea>
</template>
<script>
export default {
name: 'CellEditor',
props: ['cellContent', 'cellId'],
data () {
return {
mutableCellContent: this.cellContent
}
}
}
</script>
<style>
...
</style>
In data (mutableCellContent: this.cellContent) you are creating a copy of the prop, that's why when the parent changes, the local copy (mutableCellContent) is not updated. (If you must have a local copy, you'd have to watch the parent to update it.)
Instead, you should not keep a copy in the child component, just let the state be in the parent (and change it through events emitted in the child). This is a well known the best practice (and not only in Vue, but in other frameworks too, if I may say it).
Example:
Vue.component('cell-editor', {
template: '#celleditor',
name: 'CellEditor',
props: ['cellContent', 'cellId'],
data () {
return {}
}
});
new Vue({
el: '#app',
data: {
message: "Hello, Vue.js!"
}
});
textarea { height: 50px; width: 300px; }
<script src="https://unpkg.com/vue"></script>
<template id="celleditor">
<textarea
:value="cellContent"
#keyup.ctrl.enter="$emit('value-submit', $event.currentTarget.value)"
#keyup.esc="$event.currentTarget.value = cellContent">
</textarea>
</template>
<div id="app">
{{ message }}
<br>
<cell-editor :cell-content="message" #value-submit="message = $event"></cell-editor>
<br>
<button #click="message += 'parent!'">Change message in parent</button>
</div>
You have to create a watcher to the prop cellContent.
Vue.config.productionTip = false
Vue.config.devtools = false
Vue.config.debug = false
Vue.config.silent = true
Vue.component('component-1', {
name: 'CellEditor',
props: ['cellContent', 'cellId'],
data() {
return {
mutableCellContent: this.cellContent
}
},
template: `
<textarea
v-model="mutableCellContent"
#keyup.ctrl.enter="$emit('value-submit', mutableCellContent)"
#keyup.esc="$emit('cancel')">
</textarea>
`,
watch: {
cellContent(value) {
this.mutableCellContent = value;
}
}
});
var vm = new Vue({
el: '#app',
data() {
return {
out: "",
cellContent: ""
}
},
methods: {
toOut(...args) {
this.out = JSON.stringify(args);
},
changeCellContent() {
this.cellContent = "changed at " + Date.now();
}
}
});
<script src="https://cdn.jsdelivr.net/npm/vue/dist/vue.js"></script>
<div id="app">
<component-1 :cell-content="cellContent" #value-submit="toOut" #cancel="toOut"></component-1>
<p>{{out}}</p>
<button #click="changeCellContent">change prop</button>
</div>

Fetch data in component on initiation using parameters from Vuex store

I am new to Vue and am trying to build a simple movie app, fetching data from an API and rendering the results. I want to have an incremental search feature. I have an input field in my navbar and when the user types, I want to redirect from the dashboard view to the search results view. I am unsure of how to pass the query params from the navbar to the search results view.
Here is my App.vue component
<template>
<div id="app">
<Navbar></Navbar>
<router-view/>
</div>
</template>
<script>
import Navbar from './components/Navbar.vue'
export default {
name: 'App',
components: {
Navbar
},
}
</script>
And here is my navbar component where I have the input field
<template>
<nav class="navbar">
<h1 class="logo" v-on:click="goToHome">Movie App</h1>
<input class="search-input" v-on:keyup="showResults" v-model="query" type="text" placeholder="Search..."/>
</nav>
</template>
<script>
import router from '../router/index'
export default {
data: function () {
return {
query: this.query
}
},
methods: {
goToHome () {
router.push({name: 'Dashboard'})
},
showResults () {
//here on each key press I want to narrow my results in the SearchedMovies component
}
}
}
</script>
If I use router.push to the SearchedMovies component then I am only able to pass the query as a parameter once. I thought about using Vuex to store the query and then access it from the SearchedMovies component, but surely there is a better way of doing it?
I also read about using $emit but since my parent contains all the routes, I'm not sure how to go about this.
You don't need to redirect user anywhere. I've made a small demo to show how one might do it. I used this navbar component as you described and emit an event from it:
const movies = {
data: [
{
id: 0,
title: 'Eraserhead',
},
{
id: 1,
title: 'Erazerhead',
},
{
id: 2,
title: 'Videodrome',
},
{
id: 3,
title: 'Videobrome',
},
{
id: 4,
title: 'Cube',
},
]
};
Vue.component('navbar', {
template: '<input v-model="filter" #input="onInput" placeholder="search">',
data() {
return {
filter: '',
};
},
methods: {
onInput() {
this.$emit('filter', this.filter);
}
}
});
// this is just a request imitation.
// just waiting for a second until we get a response
// from the datasample
function request(title) {
return new Promise((fulfill) => {
toReturn = movies.data.filter(movie => movie.title.toLowerCase().indexOf(title.toLowerCase()) !== -1)
setTimeout(() => fulfill(toReturn), 1000);
});
}
new Vue({
el: '#app',
data: {
movies: undefined,
loading: false,
filter: '',
lastValue: '',
},
methods: {
filterList(payload) {
// a timeout to prevent
// instant request on every input interaction
this.lastValue = payload;
setTimeout(() => this.makeRequest(), 1000);
},
makeRequest() {
if (this.loading) {
return;
}
this.loading = true;
request(this.lastValue).then((response) => {
this.movies = response;
this.loading = false;
});
}
},
mounted() {
this.makeRequest('');
}
})
<script src="https://unpkg.com/vue"></script>
<div id="app">
<navbar v-on:filter="filterList"></navbar>
<ul v-if="!loading">
<li v-for="movie in movies" :key="movie.id">{{ movie.title }}</li>
</ul>
<p v-else>Loading...</p>
</div>
Also jsfiddle: https://jsfiddle.net/oniondomes/rsyys3rp/
If you have any problem to understand the code above let me know.
EDIT: Fixed some bugs and added a couple of comments
EDIT2(after the comment below):
Here's what you can do. Every time user inputs something inside a navbar you call a function:
// template
<navbar v-on:input-inside-nav-bar="atInputInsideNavBar"></navbar>
// script
methods: {
atInputInsideNavBar(userInput) {
this.$router.push({
path: '/filtred-items',
params: {
value: userInput
}
})
}
}
Then inside you 'searched movies' page component you can access this value so:
this.$route.params.value // returns userInput from root component

Vuejs DOM doesn't update after fetching data

I have bound an array events to a component tag <scheduler> containing events to fill in a scheduler app (dhtmlx scheduler). However, the DOM doesn't seeem to refresh itself when data is retrieved by the getEvents methods triggered when vue instance is created.
There is 2 vue files I work with: App.vue containing the main app component and the Scheduler.vue file containing the scheduler component.
The thing is that when I modify something in the Scheduler.vue file and save it, it correctly take the updated events array into account.
Scheduler parse the data in the events prop when DOM is mounted in scheduler component.
Therefore is there something I can do to get the updated array ?
Here is the App.vue:
<template>
<div id="app">
<div class="container">
<scheduler v-bind:events="events"></scheduler>
</div>
</div>
</template>
<script>
import Scheduler from './components/Scheduler.vue';
import auth from './components/auth/index'
import data from './components/data/index'
export default {
name: 'app',
components: {
Scheduler
},
data() {
return {
events: []
}
},
created() {
this.getEvents();
},
watch: {
events: function(value) {
console.log('updated');
}
},
methods: {
async getEvents() {
try {
const token = await auth.getToken(this);
const thattoken = await auth.getThatToken(this, token);
await data.getOgustData(this, token, '/calendar/events', 307310564, this.events);
} catch (e) {
console.log(e);
}
},
}
}
</script>
Here is Scheduler.vue:
<template lang="html">
<div ref="scheduler_here" class="dhx_cal_container" style='width:100%; height:700px;'>
<div class="dhx_cal_navline">
<div class="dhx_cal_prev_button"> </div>
<div class="dhx_cal_next_button"> </div>
<div class="dhx_cal_today_button"></div>
<div class="dhx_cal_date"></div>
<div class="dhx_cal_tab" name="day_tab" style="right:204px;"></div>
<div class="dhx_cal_tab" name="week_tab" style="right:140px;"></div>
<div class="dhx_cal_tab" name="month_tab" style="right:76px;"></div>
</div>
<div class="dhx_cal_header"></div>
<div class="dhx_cal_data"></div>
</div>
</template>
<script>
import 'dhtmlx-scheduler'
import 'dhtmlx-scheduler/codebase/locale/locale_fr';
import 'dhtmlx-scheduler/codebase/ext/dhtmlxscheduler_readonly.js';
export default {
name: 'scheduler',
props: {
events: {
type: Array,
default () {
return [{
id: '',
text: '',
start_date: '',
end_date: '',
}]
}
}
},
mounted() {
scheduler.config.xml_date = '%Y-%m-%d %H:%i';
// disable left buttons on lightbox
scheduler.config.buttons_left = [];
// enable cancel button on lightbox's right wing
scheduler.config.buttons_right = ['dhx_cancel_btn'];
// changing cancel button label
scheduler.locale.labels['icon_cancel'] = 'Fermer';
// hide lightbox in month view
scheduler.config.readonly_form = true;
// hide select bar in day and week views
scheduler.config.select = false;
scheduler.config.lightbox.sections = [
{
name: "description",
height: 20,
map_to: "text",
type: "textarea",
focus: true
}
];
scheduler.init(this.$refs.scheduler_here, new Date(), 'month');
scheduler.parse(this.$props.events, 'json');
},
}
</script>
<style lang="css" scoped>
#import "~dhtmlx-scheduler/codebase/dhtmlxscheduler.css";
</style>
getOgustData can't populate events in a way that Vue can observe. Since you're passing it as an argument, the array itself can be updated, but it's not a reactive array. Try
var newEvents;
await data.getOgustData(this, token, '/calendar/events', 307310564, newEvents);
this.events = newEvents;
Assigning to this.events is something Vue can notice.
Problem is solved. The issue didn't come from Vue but rather from the dhtmlx scheduler which wasn't parsing events when events was updated.
I ended up watching for any changes to events and thus, parsing it when it updates.
Thanks again for the help provided.
App.vue :
<template>
<div id="app">
<div class="container">
<scheduler v-bind:events="events"></scheduler>
</div>
</div>
</template>
<script>
import Scheduler from './components/Scheduler.vue';
import auth from './components/auth/index'
import data from './components/data/index'
import 'dhtmlx-scheduler'
export default {
name: 'app',
components: {
Scheduler
},
data() {
return {
events: []
}
},
created() {
this.getEvents();
},
watch: {
events: function(value) {
scheduler.parse(this.events, 'json');
}
},
methods: {
async getEvents() {
const token = await auth.getToken(this);
const apiToken = await auth.getApiToken(this, token);
this.events = await data.getApiData(this, apiToken, '/calendar/events', 307310564, this.events);
}
},
}
</script>