I'm making a chat system with socket.io and VueJS, so customers can talk to an admin. But when a client connects to the server, the variable in the data() updates. But the template is not updating.
Here is my code:
<template>
<div>
<div class="chats" id="chat">
<div class="chat" v-for="chat in chats">
<b>{{ chat.clientName }}</b>
<p>ID: {{ chat.clientID }}</p>
<div class="jens-button">
<img src="/icons/chat-bubble.svg">
</div>
</div>
</div>
</div>
</template>
<script>
let io = require('socket.io-client/dist/socket.io.js');
let socket = io('http://127.0.0.1:3000');
export default {
name: 'Chats',
data() {
return {
chats: [],
}
},
mounted() {
this.getClients();
this.updateClients();
},
methods: {
getClients() {
socket.emit('get clients', true);
},
updateClients() {
socket.on('update clients', (clients) => {
this.chats = clients;
console.log(this.chats);
});
}
},
}
</script>
Then I get this, the box is empty:
But I need to get this, this will only appear when I force reload the page. I don't know what I'm doing wrong...
Oke, I've found out where the problem was, in another component I used plain javascript which brokes the whole reactive stuff.
Related
How can I display frontend results.The data is showing in the console.log but not in the frontend. I need help.
HTML
<b-card class="mt-3" header="Patient Information">
<p>Name {{this.patientName}} </p>
<br><br>
<div class="graphtitle">Medical Record</div>
</b-card>
Script
import axios from "axios";
export default {
data():{},
methods: {
getPatient(){
axios.get('https://xxx/medicalRecord/api/v1/getMedicalRecord?patientID=s3333333c')
.then(response => {
this.patientName = response.data.message.patientName;
console.log(response.data.message);
})
.catch(error => alert(error));
}
}
}
In your template, you don’t need the this. Change it to:
<p>Name {{ patientName }} </p>
But the problem is that you did not define patientName as an empty string in data. So there is no reactive property.
data(): {
return {
patientName: '',
}
},
Hope this helps.
Suggestions :
Please verify response.data.message.patientName is returning the patient name or not.
In Template, You can access data properties directly by their names with out using this keyword. (It will not break anything if you will use that with this keyword as well)
To make the property reactive, You should add that in your data method.
Live Demo :
new Vue({
el: '#app',
data: {
patientName: ''
},
mounted() {
this.getPatientDetail();
},
methods: {
getPatientDetail() {
this.patientName = 'Alpha'
}
}
})
<script src="https://cdnjs.cloudflare.com/ajax/libs/vue/2.5.17/vue.js"></script>
<div id="app">
<p>{{ this.patientName }}</p>
</div>
I'm just starting to use VueJS & Tailwind, having never really used anything related to npm before.
I have the below code, making use of Tailwind & Headless UI which through debugging, I know I'm like 99% of the way there... except for the continuous error message
Uncaught ReferenceError: posts is not defined
I know this should be straight forward, but everything I've found either here or with Google hasn't worked. Where am I going wrong?
<template>
<Listbox as="div" v-model="selected">
<ListboxLabel class="">
Country
</ListboxLabel>
<div class="mt-1 relative">
<ListboxButton class="">
<span class="">
<img :src="selected.flag" alt="" class="" />
<span class="">{{ selected.name }}</span>
</span>
<span class="">
<SelectorIcon class="" aria-hidden="true" />
</span>
</ListboxButton>
<transition leave-active-class="" leave-from-class="opacity-100" leave-to-class="opacity-0">
<ListboxOptions class="">
<ListboxOption as="template" v-for="country in posts" :key="country" :value="country" v-slot="{ active, selected }">
<li :class="">
<div class="">
<img :src="country.flag" alt="" class="" />
<span :class="[selected ? 'font-semibold' : 'font-normal', 'ml-3 block truncate']">
{{ country.latin }}
</span>
</div>
<span v-if="selected" :class="">
<CheckIcon class="" aria-hidden="true" />
</span>
</li>
</ListboxOption>
</ListboxOptions>
</transition>
</div>
</Listbox>
</template>
<script>
import { ref } from 'vue'
import { Listbox, ListboxButton, ListboxLabel, ListboxOption, ListboxOptions } from '#headlessui/vue'
import { CheckIcon, SelectorIcon } from '#heroicons/vue/solid'
import axios from 'axios'
export default {
data() {
return {
response: null,
posts: undefined,
};
},
components: {
Listbox,
ListboxButton,
ListboxLabel,
ListboxOption,
ListboxOptions,
CheckIcon,
SelectorIcon,
},
mounted: function() {
axios.get('http://localhost')
.then(response => {
this.posts = response.data;
});
},
setup() {
const selected = ref(posts[30])
return {
selected,
}
},
}
</script>
The offending line is const selected = ref(posts[30]) which I know I need to somehow define posts, but I don't get how?
CAUSE OF YOUR ERROR:
You are trying to access an array element before the array is populated. Thus the undefined error.
EXPLANATION
You are using a mix of composition api and options api. Stick to one.
I am writing this answer assuming you will pick the composition api.
Follow the comments in the below snippet;
<script>
// IMPORT ONMOUNTED HOOK
import { ref, onMounted } from 'vue'
import { Listbox, ListboxButton, ListboxLabel, ListboxOption, ListboxOptions } from '#headlessui/vue'
import { CheckIcon, SelectorIcon } from '#heroicons/vue/solid'
import axios from 'axios'
export default {
// YOU DO NOT NEED TO DEFINE THE DATA PROPERTY WHEN USING COMPOSITION API
/*data() {
return {
response: null,
posts: undefined,
};
},*/
components: {
Listbox,
ListboxButton,
ListboxLabel,
ListboxOption,
ListboxOptions,
CheckIcon,
SelectorIcon,
},
// YOU DO NOT NEED THESE LIFE CYCLE HOOKS; COMPOSITION API PROVIDES ITS OWN LIFECYCLE HOOKS
/*mounted: function() {
axios.get('http://localhost')
.then(response => {
this.posts = response.data;
});
},*/
setup() {
// YOU ARE TRYING TO ACCESS AN ELEMENT BEFORE THE ARRAY IS POPULATED; THUS THE ERROR
//const selected = ref(posts[30])
const posts = ref(undefined);
const selected = ref(undefined);
onMounted(()=>{
// CALL THE AXIOS METHOD FROM WITHIN THE LIFECYCLE HOOK AND HANDLE THE PROMISE LIKE A BOSS
axios.get('http://localhost')
.then((res) => {
selected.value = res[30];
});
});
return {
selected,
}
},
}
</script>
According to your comment; you should first check if the “selected != null” before using ‘selected’ inside the template. You can use a shorthand version like this
<img :src=“selected?.flag” />
I have in Layout.vue to components one TheSidebar second TheHeader, there is a button in TheHeader to open the sidebar in TheSidebarcomponent.
I need to when I click the button in header open the sidebar:
My try:
in TheHeader:
methods: {
openSidebar() {
this.$root.$emit("open-sidebar");
},
},
in TheSidebar
data() {
return {
sidebarOpen: false,
};
},
mounted() {
this.$root.$on("open-sidebar", (this.sidebarOpen = true));
},
I'm using VUE 3 so I got this error in console: TypeError: this.$root.$on is not a function so How can communicate ?
you can use something like tiny emitter it works fine and doesn't care about parent child relationship
var emitter = require('tiny-emitter/instance');
emitter.on('open-sidebar', ({isOpen}) => {
//
});
emitter.emit('open-sidebar', {isOpen : true} );
You can only pass props to a direct child component, and
you can only emit an event to a direct parent. But
you can provide and eject from anywhere to anywhere
Per another answer, provide and eject may be your best bet in Vue 3, but I created a simple example of how to implement with props/events. Built with Vue 2 as I haven't worked with 3 yet, but should be usable in Vue 3 as well.
Parent.vue
<template>
<div class="parent">
<div class="row">
<div class="col-md-6">
<h4>Parent</h4>
<hr>
<child-one #show-child-two-event="handleShowChildTwoEvent" />
<hr>
<child-two v-if="showChildTwo" />
</div>
</div>
</div>
</template>
<script>
import ChildOne from './ChildOne.vue'
import ChildTwo from './ChildTwo.vue'
export default {
components: {
ChildOne,
ChildTwo
},
data() {
return {
showChildTwo: false
}
},
methods: {
handleShowChildTwoEvent() {
this.showChildTwo = true;
}
}
}
</script>
ChildOne.vue
<template>
<div class="child-one">
<h4>Child One</h4>
<button class="btn btn-secondary" #click="showChildTwo">Show Child Two</button>
</div>
</template>
<script>
export default {
methods: {
showChildTwo() {
this.$emit('show-child-two-event');
}
}
}
</script>
ChildTwo.vue
<template>
<div class="child-two">
<h4>Child Two</h4>
</div>
</template>
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>
I'm just starting out with VueJS and I was trying to port over a simple jQuery read more plugin I had.
I've got everything working except I don't know how to get access to the contents of the slot. What I would like to do is move some elements passed into the slot to right above the div.readmore__wrapper.
Can this be done simply in the template, or am I going to have to do it some other way?
Here's my component so far...
<template>
<div class="readmore">
<!-- SOME ELEMENTS PASSED TO SLOT TO GO HERE! -->
<div class="readmore__wrapper" :class="{ 'active': open }">
<slot></slot>
</div>
Read {{ open ? lessLabel : moreLabel }}
</div>
</template>
<script>
export default {
name: 'read-more',
data() {
return {
open: false,
moreLabel: 'more',
lessLabel: 'less'
};
},
methods: {
toggle() {
this.open = !this.open;
}
},
}
</script>
You can certainly do what you describe. Manipulating the DOM in a component is typically done in the mounted hook. If you expect the content of the slot to be updated at some point, you might need to do the same thing in the updated hook, although in playing with it, simply having some interpolated content change didn't require it.
new Vue({
el: '#app',
components: {
readMore: {
template: '#read-more-template',
data() {
return {
open: false,
moreLabel: 'more',
lessLabel: 'less'
};
},
methods: {
toggle() {
this.open = !this.open;
}
},
mounted() {
const readmoreEl = this.$el.querySelector('.readmore__wrapper');
const firstEl = readmoreEl.querySelector('*');
this.$el.insertBefore(firstEl, readmoreEl);
}
}
}
});
.readmore__wrapper {
display: none;
}
.readmore__wrapper.active {
display: block;
}
<script src="//cdnjs.cloudflare.com/ajax/libs/vue/2.4.2/vue.min.js"></script>
<div id='app'>
Hi there.
<read-more>
<div>First div inside</div>
<div>Another div of content</div>
</read-more>
</div>
<template id="read-more-template">
<div class="readmore">
<!-- SOME ELEMENTS PASSED TO SLOT TO GO HERE! -->
<div class="readmore__wrapper" :class="{ 'active': open }">
<slot></slot>
</div>
Read {{ open ? lessLabel : moreLabel }}
</div>
</template>