How to pass multiple props from parent to child component in Vue - vue.js

I'm trying to pass two properties from parent to child, but for some reason this isn't working and all the examples I've found refer to passing a single property. What I've tried to do is:
Parent vue component:
<template>
<div class="statistics_display">
<multiLineChart :rowsA="reading['A'].price_stats" :rowsB="reading['B'].price_stats"></multiLineChart>
</div>
</template>
multiLineChart vue component:
export default {
name: 'MultiLineChart',
props: ['rowsA', 'rowsB'],
mounted: function() {
console.log(this.rowsA);
}
the console log is returning undefined. If I executethe exact same code and pass a single prop, it returns the expected prop contents. What am I missing?

HTML attributes are case-insensitive, so
<multiLineChart :rowsA="reading['A'].price_stats" :rowsB="reading['B'].price_stats"></multiLineChart>
Are actually bound to props: ['rowsa', 'rowsb'].
If you want props: ['rowsA', 'rowsB']to work, use, in the template: :rows-a="..." and :rows-b="...".
See it working below.
Vue.component('multilinechart', {
template: "#mtemplate",
props: ['rowsA', 'rowsB'],
mounted: function() {
console.log(this.rowsA, this.rowsB);
}
})
new Vue({
el: '#app',
data: {
reading: {A: {price_stats: 11}, B: {price_stats: 22}}
}
});
<script src="https://unpkg.com/vue#2.5.13/dist/vue.min.js"></script>
<div id="app">
<div class="statistics_display">
<multiLineChart :rows-a="reading['A'].price_stats" :rows-b="reading['B'].price_stats"></multiLineChart>
</div>
</div>
<template id="mtemplate">
<div>I'm multilinechart</div>
</template>

Related

Vuetable2 slot in slot

I use vue(2.6.10) an Im trying to build a universal table with vuetable2 (2.0.0-beta.4).
I created a component for the general methods of vuetable.
I tried to place my "MyCustomTemplate" in the slot section of the "MyVueTable", but I got no error and nothing is shown.
My goal is to use the "MyVueTable" in other vue pages and replace the "MyCustomTemplate".
I have currently 3 entries in my data but in the List.vue component nothing is shown
List.vue
<template>
<MyVueTable :data="data" :fields="fields">
<MyCustomTemplate v-slot="vueTableTemplateSlot"/>
</MyVueTable>
</template
<script>
export default {
name:"List",
data(){
return{
data: [],
fields: [
{
name: 'vueTableTemplateSlot'
}
]
};
}
}
</script>
MyVueTable.vue
<template>
<vuetable ref="vuetable">
<slot name="vueTableTemplateSlot" slot-scope="props"/>
</vuetable>
</template>
<script>
export default {
name: 'MyVueTable',
props: ['data', 'fields'],
methods:{
//vuetable methods
}
}
</script>
MyCustomTemplate.vue
<template>
<div>
{{rowData.id}}
</div>
</template>
<script>
export default {
name: 'MyCustomTemplate',
data(){
return{
rowData: null
}
}
</script>
You can test to put your component(in List.vue) in a div or a template that will be the slot content :
<template #nameOfYourSlot>
<NameOfYourComponent>
</template>
This was answered in the official repository, you need to do this to be your custom global component: https://github.com/ratiw/vuetable-2-tutorial/wiki/lesson-17

Prop passed to child component is undefined in created method

I am using Vue.js 2.
I have a problem with passing value to the child component as a prop. I am trying to pass card to card-component.
In card-component I can access the prop in the Card goes here {{card}} section.
However when I try to access it in created or mounted methods it's undefined.
Parent:
<template>
<div class="container">
<div class="row">
<div class="col-md-8 col-md-offset-2">
<card-component :card="place.card"></card-component>
</div>
</div>
</div>
</template>
<script>
import CostComponent from './CostComponent';
import CardComponent from './CardComponent';
export default {
components: {
CostComponent, CardComponent
},
props: ['id'],
data() {
return {
place: []
}
},
created() {
axios.get('/api/places/' + this.id)
.then(response => this.place = response.data);
}
}
</script>
Child:
<template>
<div class="container">
<div class="row">
<div class="col-md-8 col-md-offset-2">
<ul class="list-unstyled">
Card goes here {{card}}
</ul>
</div>
</div>
</div>
</template>
<script>
import CardItemComponent from './CardItemComponent';
export default {
components: {
CardItemComponent
},
props: ['card'],
created() {
console.log(this.card); // undefined
},
mounted() {
console.log(this.card); // undefined
},
}
</script>
I did a lot of googling but none of the solutions I found have fixed my issue.
This is purely a timing issue. Here's what happens...
Your parent component is created. At this time it has an empty array assigned to place (this is also a problem but I'll get to that later). An async request is started
Your parent component creates a CardComponent instance via its template
<card-component :card="place.card"></card-component>
at this stage, place is still an empty array, therefore place.card is undefined
3. The CardComponent created hook runs, logging undefined
4. The CardComponent is mounted and its mounted hook runs (same logging result as created)
5. Your parent component is mounted
6. At some point after this, the async request resolves and changes place from an empty array to an object, presumably with a card property.
7. The new card property is passed down into your CardComponent and it reactively updates the displayed {{ card }} value in its template.
If you want to catch when the card prop data changes, you can use the beforeUpdate hook
beforeUpdate () {
console.log(this.card)
}
Demo
Vue.component('CardComponent', {
template: '<pre>card = {{ card }}</pre>',
props: ['card'],
created () {
console.log('created:', this.card)
},
mounted () {
console.log('mounted:', this.card)
},
beforeUpdate () {
console.log('beforeUpdate:', this.card)
}
})
new Vue({
el: '#app',
data: {
place: {}
},
created () {
setTimeout(() => {
this.place = { card: 'Ace of Spades' }
}, 2000)
}
})
<script src="https://cdn.jsdelivr.net/npm/vue"></script>
<div id="app">
<card-component :card="place.card" />
</div>
See https://v2.vuejs.org/v2/guide/instance.html#Lifecycle-Diagram
If place is meant to be an object, you should not be initialising it as an array. Also, if your CardComponent relies on data being present, you may want to conditionally render it.
For example
data () {
return { place: null }
}
and
<card-component v-if="place" :card="place.card"></card-component>
then CardComponent will only be created and mounted after place has data.
Make sure you have props: true in the router file. It is a simple solution but many of us forget this.
{
path: '/path-to',
name: 'Name To',
component: Component,
props: true
}

Vuejs props use in the client component

Hi I'm trying to pass a value to a child component as props and trying to use this value in child's created hook but it's not getting set. See example below,
<!-- Parent component -->
<template>
<div>
<details
:customer_id = this.customer_id
:foo = "bar" />
</div>
</template>
<script>
import CustomerDetail from './CustomerDetails';
export default {
name: 'Customer',
data: function() {
return {
customer_id: '',
}
components: {
'detail': CustomerDetail
},
created: function() {
var id = this.$route.params.id;
this.customer_id = id;
} // created
}
</script>
<!-- Details component -->
<template>
<div>
<h1>{{foo}}</h1>
</div>
</template>
<script>
export default {
name: 'CustomerDetail',
props: ['customer_id', 'foo']
created: function() {
console.log(this.customer_id); <!-- -->
} // created
}
</script>
As shown in above code, when child component is rendered, may times the customer_id in created() hook of child component is undefined. It shows up occasionally if hotloading happens on the same view. How do I make sure that this value always available. In this case I want to do server call to get customer details. At the same time {{foo}} correctly show value 'bar'. What am I missing? Any help is appreciated.
Registered child components actually have direct access to the route params, since you are using Dynamic Route Matching, you can simply get the dynamic params via $routes.params.* from the child components themselves.
const Customer = {
template: `
<div>
<h3>Customer ID: {{$route.params.id}}</h3>
</div>
`
}
const routes = [
{ path: '/customers/:id', component: Customer }
];
new Vue({
el: '#app',
router: new VueRouter({
routes
}),
data() {
return {
bar: 'Doh!',
//customer_id: '',
}
},
components: {
CustomerDetails: {
template: `
<div>
<h1>Value from parent: <em>{{foo}}</em></h1>
</div>
`,
props: ['foo']
}
}
})
<script src="https://cdnjs.cloudflare.com/ajax/libs/vue/2.5.17/vue.js"></script>
<script src="https://cdnjs.cloudflare.com/ajax/libs/vue-router/3.0.2/vue-router.min.js"></script>
<div id="app">
<div>
<label>View profile:</label>
<router-link to="/customers/john">John</router-link>
<router-link to="/customers/doe">Doe</router-link>
<router-view></router-view>
<div>
<customer-details :foo="bar"></customer-details>
</div>

How to make a template variable non-reactive in Vue

I have an edit form with variables held in the data(). I don't want the title of the edit page to update yet I want to maintain the v-model sync of data between the input and data. What's the simplest way to make the title non-reactive in the h1 tag? Mr You has to have something up his sleeve for this..
<template>
<div>
<h1>{{ title }}</h1>
<input v-model="title">
</div>
</template>
<script>
export default {
data: {
title: 'Initial value'
}
}
</script>
The Vue docs recommend Object.freeze() on the returned object in data() to disable reactivity on properties:
data() {
return Object.freeze({ title: 'Initial value' })
}
But the caveat is it freezes all properties (it doesn't look like there's a way to freeze only some properties using this method), and using v-model with this causes console errors (Cannot assign to read only property).
Vue.config.devtools = false;
Vue.config.productionTip = false;
new Vue({
el: '#app',
data() {
return Object.freeze({
message: 'Hello Vue.js!',
})
}
})
<script src="https://unpkg.com/vue#2.5.17"></script>
<div id="app">
<p>{{ message }}</p>
<input v-model="message"> <!-- XXX: Cannot use v-model with frozen property. This will cause a console error. -->
</div>
Alternatively, you could arbitrarily remove the reactivity from any configurable data property by redefining it with writeable: false:
methods: {
removeReactivity() {
Object.defineProperty(this, 'title', {value: null, writeable: false});
}
}
Vue.config.devtools = false;
Vue.config.productionTip = false;
new Vue({
el: '#app',
data() {
return {
message: 'Hello Vue.js!',
}
},
methods: {
removeReactivity() {
Object.defineProperty(this, 'message', {value: null, writeable: false});
}
}
})
<script src="https://unpkg.com/vue#2.5.17"></script>
<div id="app">
<p>{{ message }}</p>
<input v-model="message">
<div>
<button #click="removeReactivity">
Remove reactivity for <code>message</code>
</button>
</div>
</div>
You could potentially use v-once directive for your purpose if you don't want to create a separate variable for input. From the docs:
Render the element and component once only. On subsequent re-renders,
the element/component and all its children will be treated as static
content and skipped.
new Vue({
el: "#app",
data: {
title: "initial value"
}
})
<script src="https://cdn.jsdelivr.net/npm/vue#2.5.17/dist/vue.min.js"></script>
<div id="app">
<input v-model="title">
<p>Reactive title: {{ title }}</p>
<p v-once>Static title: {{ title }}</p>
</div>
If you don't want the input to change the value of your data item, use value to bind it rather than the two-way v-model. Then it just acts as an initializer for the input.
If you want to have two values, one that doesn't change and one that does that gets initialized from the other, you need to have two data items. The non-changing one can be a prop with a default value. The other is a data member which, if you use a data function, can initialize itself to the prop value.
new Vue({
el: '#app',
props: {
initTitle: {
default: 'Initial value'
}
},
data() {
return {
title: this.initTitle
};
}
});
<script src="https://unpkg.com/vue#latest/dist/vue.js"></script>
<div id="app">
<h1>{{ initTitle }}</h1>
<input v-model="title">
<div>Title is "{{title}}"</div>
</div>
You could alternatively use the little-known $options properties to define your title as a sort of internal constant rather than a prop. I am of mixed feelings about whether this is a good design approach or a step too weird.
new Vue({
el: '#app',
initTitle: 'Initial value',
data() {
return {
title: this.$options.initTitle
};
}
});
<script src="https://unpkg.com/vue#latest/dist/vue.js"></script>
<div id="app">
<h1>{{ $options.initTitle }}</h1>
<input v-model="title">
<div>Title is "{{title}}"</div>
</div>
Working backwards from the contents of this blog...
It appears that when you create an object for Vue, it creates the properties with reactive getters and setters. If you then append a property to that object out-of-band, then it won't get the reactive capability, but will still be accessible as a value.
This should solve it for you:
<template>
<div>
<h1>{{ titleContainer.value }}</h1>
<input v-model="title">
</div>
</template>
<script>
export default {
data: {
titleContainer: {}
}
}
titleContainer.value = "Initial Value"
</script>
There is no easy way to solve your problem with Vue as is since Vue automatically injects reactive getters and setters for all object properties. You could use Object.freeze() on the variable to remove reactivity BUT it would apply across the whole object itself which is not what you want.
I created a fork out of vue called vue-for-babylonians to restrict reactivity and even permit some object properties to be reactive. Check it out here.
With it, you can tell Vue to not make any objects which are stored in vue or vuex from being reactive. You can also tell Vue to make certain subset of object properties reactive. You’ll find performance improves substantially and you enjoy the convenience of storing and passing large objects as you would normally in vue/vuex.

Passing a prop down 2 layers of children?

I have a component and I pass in an id as a prop:
<comments myId="1"></comments>
And on the comments component I have it as a prop:
props: [
'myId',
],
Inside this comments component template I have another component
<btn id="{{ this.myId }}"></btn>
But i cannot seem to pass the prop down - I get the error:
Interpolation inside attributes has been removed. Use v-bind or the colon shorthand instead. For example, instead of <div id="{{ val }}">, use <div :id="val">.
I don't see why I need to use :, I'm happy to pass the id as a string.
How can I resolve the error, and pass down the prop?
you can write down
<btn :id="myId"></btn>
to pass the props in to component.
syntax for passing props is this we can bind variable to component using bind we don't need to interpolate values there.
Vue.component('child', {
template: '#child',
props: ['id']
});
Vue.component('childchild', {
template: '#childchild',
props: ['id']
});
new Vue({
el: '#app',
data: {
},
created: function() {
},
methods: {
}
});
<script src="https://cdnjs.cloudflare.com/ajax/libs/vue/2.1.3/vue.js"></script>
<div id="app">
<child id="1000"></child>
</div>
<template id="child">
<childchild :id="id"></childchild>
</template>
<template id="childchild">
<h1>{{ id }}</h1>
</template>