VueJS change date format - vue.js

Now VueJS display me date in format 2021-02-24 00:12:42, but how i can change display only 00:12? Without year, month, date and seconds?
In vue i use:
<div class="jhistory" v-for="game in histories" :key="game.game_id">
{{ game.date }}
</div>
<script>
export default {
data() {
return {
histories: {},
}
},
mounted() {
this.$root.isLoading = true
this.getHistory();
},
methods: {
getHistory() {
this.$root.axios.post('/jackpot/history').then(res => {
this.histories = res.data;
this.$root.isLoading = false;
});
}
}
}
</script>

One way to do this is to create a component method that converts the string into a Date object, uses Date.prototype.toTimeString(), and takes only the first 5 characters, which contains only the hh:mm portion. Another simpler way is to just extract the substring with String.prototype.substr(), assuming the format never changes.
export default {
methods: {
toTime(date) {
// Option 1
return new Date(date).toTimeString().substr(0,5)
// Option 2
return date.substr(11,5)
}
}
}
Then use the method in your template:
{{ toTime(game.date) }}
new Vue({
el: '#app',
data: () => ({
game: {
date: '2021-02-24 00:12:42'
}
}),
methods: {
toTime(date) {
return new Date(date).toTimeString().substr(0,5)
// OR
// return date.substr(11,5)
}
}
})
<script src="https://unpkg.com/vue#2.6.12"></script>
<div id="app">
<p>{{ toTime(game.date) }}</p>
</div>

Related

How to display the value of a variable

Gets data from collection:
const pageTitles = {
homePage: 'Main'
...
}
export default pageTitles
If I make all this way:
<div><span>{{pageTitles.homePage}}</span></div>
everything is ok.
But i need to show the value depending on route. I tried to make this:
pageTitle(){
if (this.$route.path === '/'){
return pageTitles.homePage
}
}
and in div I have {{pageTitle}}, but it doesn't work. Why it doesn't work?
you've omitted the this keyword before pageTitles.homePage in your computed property
pageTitle(){
if (this.$route.path === '/'){
return this.pageTitles.homePage
}
}
It should work, Here you go :
new Vue({
el: '#app',
data: {
pageTitles: {
homePage: 'Main'
}
},
computed: {
pageTitle() {
return this.pageTitles.homePage
}
}
})
<script src="https://cdnjs.cloudflare.com/ajax/libs/vue/2.5.17/vue.js"></script>
<div id="app">
<h2>{{ pageTitle }}</h2>
</div>

Replace tag dynamically returns the object instead of the contents

I'm building an chat client and I want to scan the messages for a specific tag, in this case [item:42]
I'm passing the messages one by one to the following component:
<script>
import ChatItem from './ChatItem'
export default {
props :[
'chat'
],
name: 'chat-parser',
data() {
return {
testData: []
}
},
methods : {
parseMessage(msg, createElement){
const regex = /(?:\[\[item:([0-9]+)\]\])+/gm;
let m;
while ((m = regex.exec(msg)) !== null) {
msg = msg.replace(m[0],
createElement(ChatItem, {
props : {
"id" : m[1],
},
}))
if (m.index === regex.lastIndex) {
regex.lastIndex++;
}
}
return msg
},
},
render(createElement) {
let user = "";
let msg = this.parseMessage(this.$props.chat.Message, createElement)
return createElement(
'div',
{
},
[
// "hello",// createElement("render function")
createElement('span', '['+ this.$props.chat.Time+'] '),
user,
msg,
]
)
}
};
</script>
I thought passing createElement to the parseMessage method would be a good idea, but it itsn't working properly as it replaces the tag with [object object]
The chatItem looks like this :
<template>
<div>
<span v-model="item">chatITem : {{ id }}</span>
</div>
</template>
<script>
export default {
data: function () {
return {
item : [],
}
},
props :['id'],
created() {
// this.getItem()
},
methods: {
getItem: function(){
obj.item = ["id" : "42", "name": "some name"]
},
},
}
</script>
Example :
if the message looks like this : what about [item:42] OR [item:24] both need to be replaced with the chatItem component
While you can do it using a render function that isn't really necessary if you just parse the text into a format that can be consumed by the template.
In this case I've kept the parser very primitive. It yields an array of values. If a value is a string then the template just dumps it out. If the value is a number it's assumed to be the number pulled out of [item:24] and passed to a <chat-item>. I've used a dummy version of <chat-item> that just outputs the number in a <strong> tag.
new Vue({
el: '#app',
components: {
ChatItem: {
props: ['id'],
template: '<strong>{{ id }}</strong>'
}
},
data () {
return {
text: 'Some text with [item:24] and [item:42]'
}
},
computed: {
richText () {
const text = this.text
// The parentheses ensure that split doesn't throw anything away
const re = /(\[item:\d+\])/g
// The filter gets rid of any empty strings
const parts = text.split(re).filter(item => item)
return parts.map(part => {
if (part.match(re)) {
// This just converts '[item:24]' to the number 24
return +part.slice(6, -1)
}
return part
})
}
}
})
<script src="https://unpkg.com/vue#2.6.10/dist/vue.js"></script>
<div id="app">
<template v-for="part in richText">
<chat-item v-if="typeof part === 'number'" :id="part"></chat-item>
<template v-else>{{ part }}</template>
</template>
</div>
If I were going to do it with a render function I'd do it pretty much the same way, just replacing the template with a render function.
If the text parsing requirements were a little more complicated then I wouldn't just return strings and numbers. Instead I'd use objects to describe each part. The core ideas remain the same though.

How do I trigger a recalculation in a Vue app?

I'm working on a project with Vue and VueX. In my component, I have a calculated method that looks like this:
...mapState([
'watches',
]),
isWatched() {
console.log('check watch');
if (!this.watches) return false;
console.log('iw', this.watches[this.event.id]);
return this.watches[this.event.id] === true;
},
And in my store, I have the following:
addWatch(state, event) {
console.log('add', state.watches);
state.watches = {
...state.watches,
[event]: true,
};
console.log('add2', state.watches);
},
However, this doesn't trigger a recalculation. What's going on?
Try changing return this.watches[this.event.id] === true;
to
return this.$store.commit("addWatch", this.event.id);
The code you have shown is correct, so the problem must be elsewhere.
I assume by 'calculated method' you mean computed property.
Computed properties do not watch their dependencies deeply, but you are updating the store immutably, so that is not the problem.
Here is a bit of sample code to give you the full picture.
Add event numbers until you hit '2', and the isWatched property becomes true.
Vue.use(Vuex);
const mapState = Vuex.mapState;
const store = new Vuex.Store({
state: {
watches: {}
},
mutations: {
addWatch(state, event) {
state.watches = { ...state.watches, [event]: true };
}
}
});
new Vue({
el: "#app",
store,
data: {
numberInput: 0,
event: { id: 2 }
},
methods: {
addNumber(numberInput) {
this.$store.commit("addWatch", Number(numberInput));
}
},
computed: {
...mapState(["watches"]),
isWatched() {
if (!this.watches) return false;
return this.watches[this.event.id] === true;
}
}
});
<script src="https://cdnjs.cloudflare.com/ajax/libs/vuex/3.1.0/vuex.min.js"></script>
<script src="https://cdnjs.cloudflare.com/ajax/libs/vue/2.5.17/vue.js"></script>
<div id="app">
<div>Watches: {{ watches }}</div>
<div>isWatched: {{ isWatched }}</div>
<br>
<input v-model="numberInput" type="number" />
<button #click="addNumber(numberInput)">
Add new event
</button>
</div>

Adding a "Default" image to my <img> (VUE)

I have an area where people can upload their own user-image. But if they do not, I would like to display a default one.
After some googling, I found I can do so by doing something like -
<img :src="creatorImage" #error="defaultAvatar">
But, I am not sure how to then created a method to pass the correct (default) image into it.
I did it with a computed property, like this:
<template>
<img :src="creatorImage" #error="imageError = true"/>
</template>
<script>
...
data() {
return {
imageError: false,
defaultImage: require("#/assets/imgs/default.jpg")
};
},
computed: {
creatorImage() {
return this.imageError ? this.defaultImage : "creator-image.jpg";
}
}
...
</script>
I would suggest creating a component for this, as it sounds like something that will be used on more places.
JsFiddle example
Component
Vue.component('img-with-default', {
props: ['defaultImg'],
data: function () {
return {
defaultAvatar: this.defaultImg || 'https://cdn0.iconfinder.com/data/icons/crime-protection-people/110/Ninja-128.png'
}
},
computed:{
userImage: function() {
if(this.uploadedImg != null) {
return this.uploadedImg;
} else {
return this.defaultAvatar;
}
}
},
template: '<img :src="userImage">'
})
And using the commponent would be
HTML
<div id="editor">
<img-with-default></img-with-default>
<img-with-default default-img="https://cdn3.iconfinder.com/data/icons/avatars-15/64/_Ninja-2-128.png" ></img-with-default>
</div>
JS
new Vue({
el: '#editor'
})
With this you have the default image.
If you want you can create a component that would display passed img src or the default one.
Component
Vue.component('img-with-default', {
props: ['imgSrc'],
data: function () {
return {
imageSource: this.imgSrc || 'https://cdn0.iconfinder.com/data/icons/crime-protection-people/110/Ninja-128.png'
}
},
template: '<img :src="imageSource">'
})
and to use it
HTML
<div id="editor">
<img-with-default></img-with-default>
<img-with-default img-src="https://cdn3.iconfinder.com/data/icons/avatars-15/64/_Ninja-2-128.png" ></img-with-default>
</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