I am struggling to update the interpolation of thing.
This simple function should change the value of the data but instead does nothing.
Chrome logs the change of thing in the console but the HTML does not update.
<template>
<div class="container-xl pb-5">
<button class="mb-2 btn-lg selected-dropdown" #click="dropSelect('B')">
{{ thing }}
</button>
</div>
</template>
<script lang="ts">
import { defineComponent } from "vue";
export default defineComponent({
data() {
return {
thing: "A",
};
},
methods: {
dropSelect(thing: any) {
console.log(thing);
return this.thing;
},
},
});
</script>
Try to update your data property instead of returning:
dropSelect(thing: any) {
this.thing = thing
},
One small observation : Use this.thing = thing instead of return this.thing
Demo :
new Vue({
el: '#app',
data: {
thing: "A"
},
methods: {
dropSelect(thing) {
this.thing = thing;
}
}
})
<script src="https://cdnjs.cloudflare.com/ajax/libs/vue/2.5.17/vue.js"></script>
<div id="app">
<button #click="dropSelect('B')">
{{ thing }}
</button>
</div>
Related
is it possible to data bind a function in Vue?
In the template I have something like: <title> {{nameofFunction()}}</title>
When I run it, it just says native function on the page.
Thanks.
There is also such thing as "computed property" in Vue, designed to do exactly this:
<template>
<div id="example">
<p>Original message: "{{ message }}"</p>
<p>Computed reversed message: "{{ reversedMessage }}"</p>
</div>
</template>
<script>
export default {
data:() => ({
message: 'Hello'
}),
computed: {
// a computed getter
reversedMessage: function () {
// `this` points to the vm instance
return this.message.split('').reverse().join('')
}
}
}
</script>
yes you can. Could you share how are you defining your data options?
Here I have an example that works both in Vue2 and Vue3
<template>
<div id="app">
<h1>{{messageHelloFn()}}</h1>
</div>
</template>
<script>
export default {
data() {
return {
messageHelloFn: (name = 'Lucas') => {
return `Hello ${name}`
}
};
}
};
</script>
Live example: https://codepen.io/LucasFer/pen/abywRMW
a.js
const func = (str) => str
export default fn
<template>
<div id="app">
<div v-for="item in items">
{{ getTime(item) }}
</div>
<div>
{{ fn('a') }}
</div>
<div>
{{ func('b') }}
</div>
</div>
</template>
<script>
import func from './a.js'
export default {
data () {
return {
items: ['123123', '456456'],
fn: (str) => str
}
},
methods: {
getTime (v) {
return v + '123'
}
}
};
</script>
I can't seem to get the library hashids to work with vue.js
The preferend method of how i want to work with it is:
<template>
<div class="container">
{{ hashids.encode('1') }}
</div>
</template>
<script>
const Hashids = require("hashids")
export default {
data () {
return {
Hashids: Hashids,
}
},
}
</script>
Try to initialize the Hashid in mounted hook like :
<template>
<div class="container">
{{ Hashids.encode('1') }}
</div>
</template>
<script>
const Hashids = require("hashids")
export default {
data() {
return {
Hashids: null,
}
},
mounted() {
this.Hashids = new Hashids.default()
}
}
</script>
This made it work!
main component:
<template>
<spelling-quiz v-bind:quiz="quiz"></spelling-quiz>
</template>
<script>
var quiz = {
text: "blah:,
questions: ['blah blah']
}
import spellingQuiz1 from './spellingQuiz1.vue';
export default {
components: {
spellingQuiz: spellingQuiz1
},
data: function(){
return{
quiz: quiz
}
}
};
</script>
spelling-quiz component - HTML
<template>
<div>
<br>
<div v-for="(question, index) in quiz.questions">
<b-card v-bind:header="question.text"
v-show="index === qIndex"
class="text-center">
<b-form-group>
<b-form-radio-group
buttons
stacked
button-variant="outline-primary"
size="lg"
v-model="userResponses[index]"
:options="question.options" />
</b-form-group>
<button v-if="qIndex > 0" v-on:click="prev">
prev
</button>
<button v-on:click="next">
next
</button>
</b-card>
</div>
<b-card v-show="qIndex === quiz.questions.length"
class="text-center" header="Quiz finished">
<p>
Total score: {{ score() }} / {{ quiz.questions.length }}
</p>
</b-card>
</div>
</template>
spelling-quiz component - JS
<script>
export default{
props:{
quiz: {
type: Object,
required: true
},
data: function(){
return{
qIndex: 0,
userResponses: Array(quiz.questions.length).fill(false)
};
},
methods:{
next(){
this.qIndex++;
},
prev(){
this.qIndex--;
},
score(){
return this.userResponses.filter(function(val){return val == 'correct'}).length;
}
}
}
};
</script>
I am getting the following error:
[Vue warn]: Property or method "qIndex" is not defined on the instance but referenced during render. Make sure that this property is reactive, either in the data option, or for class-based components, by initializing the property.
I am also getting the same error for "userReponses".
I do not understand the error, and I have some research but the examples do not really apply to my issue.
Question:
Why is my data not accessible? If I refer to just this component it works, but as a child component it throws this error. I am not sure how I can fix it.
You have a missing } after the props. Currently your data attribute live in your props attribute. data should live on the root object. Should be structured like this:
export default {
name: "HelloWord",
props: {
quiz: {
type: Object,
required: true
}
},
data: function() {
return {
test: 100
};
},
methods: {
next() {},
prev() {},
score() {}
}
};
Can I pass in a template string and also dynamically pass in a property so that I can make it reactive? In the example below I would like message to be reactive, but I don't want to have to predefine it on the data option.
<div id="vue">
<component :is="string && {template:string}"/>
</div>
new Vue({
el:'#vue',
data(){
return {
string:undefined,
}
},
created(){
//setTimeout to simulate ajax call
setTimeout(()=> this.string = '<div><h1 v-for="n in 1">Hello! </h1><input v-model="message" placeholder="edit me"><p>Message is: {{ message }}</p> </div>', 1000)
}
})
https://jsfiddle.net/kxtsvtro/5/
You can specify the data in the same way you specify the template: just interpolate it into the component spec.
new Vue({
el: '#vue',
data() {
return {
string: undefined,
dataObj: undefined
}
},
created() {
//setTimeout to simulate ajax call
setTimeout(() => {
this.string = '<div><h1 v-for="n in 1">Hello!</h1><input v-model="message" placeholder="edit me"><p>Message is: {{ message }}</p></div>';
this.dataObj = {
message: 'initial'
};
}, 1000)
}
})
<script src="//unpkg.com/vue#latest/dist/vue.js"></script>
<div id="vue">
<component :is="string && {template:string, data: function() { return dataObj}}" />
</div>
It looks like what you want is a component with a <slot> that you can dump a custom component into. If you're trying to compose components that's probably the easiest way to do it.
You can use Props, but I am not sure if this is the best way to do it :) here is an example:
new Vue({
el:'#vue',
data(){
return {
string:undefined,
message:''
}
},
created(){
//setTimeout to simulate ajax call
setTimeout(()=> this.string = '<div><h1 v-for="n in 1">Hello!</h1><input v-model="message" placeholder="edit me"><p>Message is: {{ message }}</p></div>', 1000)
}
})
<script src="https://cdn.jsdelivr.net/npm/vue#2.5.13/dist/vue.min.js"></script>
<div id="vue">
<component :is="string && {template:string, props:['message']}" :message="message"/>
</div>
Here's a problem that I want to solve:
I have a button that when is pressed must append my-component to a dom.
If it is pressed 2 times there must be 2 <p> tegs. How can I achieve this?
js:
<script>
Vue.component('my-component', {
template: "<p>hello</p>",
})
var vue = new Vue({
el: "#App",
data: {},
methods: {
append: function() {
// unknown code here
}
}
})
</script>
html:
<div id = "App">
<button #click="append" class="btn btn-primary">Spawn stuff!</button>
</div>
Here is one way you could do that. This code iterates over a counter using v-for to iterate over a range.
Vue.component('my-component', {
template: "<p>hello</p>",
})
var vue = new Vue({
el: "#App",
data: {
hellocount: 0
},
methods: {
append: function() {
// unknown code here
this.hellocount++
}
}
})
<script src="https://unpkg.com/vue#2.2.6/dist/vue.js"></script>
<div id="App">
<my-component v-for="n in hellocount" :key="n"></my-component>
<button #click="append" class="btn btn-primary">Spawn stuff!</button>
</div>
This is a little atypical; normally you will drive the components rendered from actual data, as #RoyJ suggests in your comments.
From your comment below, you could build a form something like this.
Vue.component('my-input', {
props:["value", "name"],
data(){
return {
internalValue: this.value
}
},
methods:{
onInput(){
this.$emit('input', this.internalValue)
}
},
template: `
<div>
{{name}}:<input type="text" v-model="internalValue" #input="onInput">
</div>
`,
})
var vue = new Vue({
el: "#App",
data: {
form:{
name: null,
email: null,
phone: null
}
},
methods:{
append(){
const el = prompt("What is the name of the new element?")
this.$set(this.form, el, null)
}
}
})
<script src="https://unpkg.com/vue#2.2.6/dist/vue.js"></script>
<div id="App">
<my-input v-for="(value, prop) in form"
:key="prop"
v-model="form[prop]"
:name="prop">
</my-input>
<button #click="append">Add New Form Element</button>
<div>
Form Values: {{form}}
</div>
</div>
The code defines a form object and iterates over the properties of the form to render inputs for each property.
This is obviously extremely naive, handles only input texts, etc. But hopefully you get the idea.