Nuxt / Vue : Component call a Method in a page - vue.js

There is my issue:
My page listing.vue list all products.
Theses products are in a Component, Product.vue.
In this component, there is a button to add this product to a selection, displaying on the listing.vue.
page/listing.vue :
<template>
<div>
<product v-for="...." />
<section>
<ul>
<li>Produit 1</li>
<li>Produit 3</li>
</section>
</div>
</template>
<script>
export default {
methods: {
addToSelection(id) {
// Code to add Product to <ul> //
}
}
}
</script>
component/product.vue:
<template>
<div>
{{ product.title }}
<button #click="addToSelection(product.id)">
Add product to selection
</button>
</div>
</template>
<script>
export default {
props: ['product'],
}
</script>
The problem is nuxt render an error:
the addToSelection method is unknown.

You should emit from your children to your parent
Product.vue
<button #click="emitProductToParent(product.id)">
...
methods: {
emitProductToParent(id) {
this.$emit('input', id)
}
}
Listing.vue
<Product #input="addToSelection" v-for="...." />
You cannot use a method that is not in the component your event listener is on. And even if you could, this is not the way to do. Use:
props to pass things down to children
emit to pass things up to parents
As explained in the official documentation here: https://v2.vuejs.org/v2/guide/components.html#Listening-to-Child-Components-Events

Related

Vue3, Render parent div only if slot inside of it has content

I'm trying to render a header only if there's a text or a populated slot inside of it.
I tried:
<div
class="flex py-sm px-md w-full align-middle rounded-t-xl"
v-if="props.title || $slots.header"
:class="[`bg-${props.headerColor}`]"
>
<p class="text-bo-xl font-bold" :class="`text-${props.titleTextColor}`">
{{ props.title }}
</p>
<slot name="header"></slot>
</div>
But the div renders anyway, even if the slot is empty. I think it considers the slot present even if it's not populated.
Any ideas?
sorry for the late response. If I utilize computed() it seems to work:
<template>
<section>
<h4>lorem</h4>
<div v-if="hasHeaderSlot">
<h2>ipsum</h2>
<slot name="header"></slot>
</div>
</section>
</template>
<script>
import { computed } from 'vue';
export default {
setup(_, { slots }) {
const hasHeaderSlot = computed(() => slots.header && slots.header());
return {
hasHeaderSlot,
};
},
};
</script>
I hope this helps. With best regards

VueJS: How can I pass params into a component?

I am new to vueJS.
What I want to do is passing parameters to a component, depending on the selection of the routes. Here is my App.vue:
<template>
<div id="main">
<header>
<h1 style="color:red">{{msg}}</h1>
</header>
<div>
<aside class="sidebar">
<router-link v-for="el in this.$router.options.routes" :to="el">
{{el.name}}
</router-link>
</aside>
<SubMenu></SubMenu>
<div class="content">
<router-view></router-view>
</div>
</div>
</div>
</template>
<script>
import SubMenu from './components/SubMenu.vue'
export default {
components: {
'SubMenu': SubMenu
},
data() {
return {
msg: 'Welcome to Your Vue.js App' }
}
}
</script>
<style>
#import 'style.css';
#import 'grid.css';
</style>
and the SubMenu component I would like to make dynamic:
<template>
<div>
something dynamic
</div>
</template>
How can I pass some parameters to use in the component?
thank you
Your App.vue can be like this:
<template>
<div id="main">
<header>
<h1 style="color:red">{{msg}}</h1>
</header>
<div>
<aside class="sidebar">
<router-link v-for="el in this.$router.options.routes" :to="el">
{{el.name}}
</router-link>
</aside>
<SubMenu :menuTitle="subMenuTitle"></SubMenu>
<div class="content">
<router-view></router-view>
</div>
</div>
</div>
</template>
<script>
import SubMenu from './components/SubMenu.vue';
export default {
components: {
SubMenu
},
data() {
return {
subMenuTitle: "This is the sub menu",
msg: 'Welcome to Your Vue.js App'
}
}
}
</script>
<style>
#import 'style.css';
#import 'grid.css';
</style>
The SubMenu.vue component could be like this:
<template>
<div>
<h2>{{ menuTitle }}</h2>
something dynamic
</div>
</template>
<script>
export default {
name: "SubMenu",
props: {
menuTitle: String,
}
}
</script>
In the SubMenu component that was used in App.vue, notice the colon that appears before the menuTitle attribute. When you do that before an attribute, the value of that attribute would be evaluated by Vue and passed to the component. You can pass literal Javascript expressions or items in your App.vue component.
In the SubMenu component, you can use the props in whatever way you can. If the prop's value is an array, you can use the v-for directive with it to create a list of items in the SubMenu.
Welcome to SO,
In Vue.js passing parameters to components is called "Props"
You can pass props to your SubMenu like below
<SubMenu :id="12345" someText="Some Text About Something" :dataArray="[1,2,3,4,5]" />
then inside your SubMenu component you can define Prop Types as below
props: ['dataArray']
or
props: {
dataArray: {
type: Array,
default: []
}
}
After that you can use the data you passed to your liking
You can also read up on this Vue Documentation regarding the Props, which has much more detailed explanations about various Props related stuff and sample code
Ok many thanks to both.
But what if I would like to pass something that depends on the voices in router-link? I mean, router-link prints a menu with 4 voices...what if I would like a behavior like this:
click on voice1 in router-link ---> pass this object ['input1', 'input2'] to SubMenu
click on voice2 in router-link ---> pass this other object ['input3', 'input4', 'input5'] to SubMenu
and so on.
thanks again :)

How to pass props to sibling and child component in vue

The structure of my code is like this:
So in the Product component, I am making an API call:
<template>
<button class="btn button col-2" #click="addToCart()">
Add to cart
</button>
</template>
<script>
methods:{
addToCart: function () {
let amount = this.itemsCount !== "" ? this.itemsCount : 1;
if(this.variationId != null) {
this.warningMessage = false;
cartHelper.addToCart(this.product.id, this.variationId, amount, (response) => {
this.cartItems = response.data.attributes.items;
});
} else {
this.warningMessage = true;
}
console.log(this.cartItems)
},
}
</script>
And what I am trying to do is the response (this.cartItems) should be shown in Cart component. And my Navbar component:
<template>
<nav class="navbar navbar-expand-lg shadow">
<div class="container navbar-container">
<div class="navbar navbar-profile">
<div class="dropdown">
<button class="btn dropdown-toggle" type="button" id="dropdownCart" data-toggle="dropdown"
aria-haspopup="true" aria-expanded="false">
<i class="fa fa-fw fa-cart-arrow-down"></i>
<span></span>
</button>
<div #click="$event.stopPropagation()">
<CartBox :cartItems="cartItems"/>
</div>
</div>
</div>
</div>
</nav>
</template>
<script>
export default {
props: {
cartItems:Object
},
components: {CartBox},
}
And CartBox:
<template>
<Cart/>
</template>
<script>
import Cart from '../components/Cart'
export default {
components: {
Cart
}
}
</script>
And my Cart component:
<template>
<div
class="dropdown-menu cart"
aria-labelledby="triggerId"
>
<div class="inner-cart">
<div>
<div class="cart-items">
<div>
<a class="remove">Remove</a>
</div>
</div>
</div>
<hr/>
<div class="cart-items-total">
<span>Total:</span>
Clear Cart
</div>
<hr/>
<router-link :to="{name: 'order'}" class="btn button-secondary">Go To Cart</router-link>
</div>
</div>
</template>
<script>
export default {
computed: {
},
methods: {
}
};
</script>
I am really confused how to pass the props to sibling component and then the child component but if you could pass it to Cart component, that would really help me.
There are two approaches for your request:
1. Using props, provide and inject
This could be accomplished with Provide / inject, after passing your response to a parent. Basically, you will emit your response from your Product component to a parent, maybe like your App.vue as the prop myData, then you provide it for every child, no matter where it is nested, like this:
provide: {
providedData: this.myData
}
In any child you can now use:
inject: ['providedData']
Please note, that this data will only be available if your Product component received it. The second approach is recommended.
2. Using a store
Using a store like vuex is a bit more complex than approach 1, but it will save a lot of time in the future. You would recieve your response in your Product component, dispatch it to the store and could call the state of information from this store anywhere in your app. See further information in this documentation: Vuex | Getting Started

Passing v-model into a checkbox inside a Component in Vue 3?

I want to embed a checkbox inside a Vue3 Component and have the v-model binding passed down to the checkbox.
Inside the Component:
<!-- Tile.vue -->
<template>
<div>
<input type=checkbox v-model="$attrs">
</div>
</template>
<script>
export default {inheritAttrs: false}
</script>
Then in an outside file:
<template>
<Tile value="carrot" v-model="foods" />
<Tile value="tomatoes" v-model="foods" />
</template>
<script setup>
var foods = ref([]);
</script>
How do I achieve this?
The documentation says that v-model is just a shorthand for :modelValue and #update:modelValue but this is not universal as Vue obviously behaves differently for form elements such as smartly listening to onchange instead of oninput and modifying the property checked instead of value depending on the node.
If I use v-model on the outer component, how do I forward it to the checkbox and get the same smart behavior that Vue has?
I have found tons of controversial information. Some recommend using #input event (Vue 3 custom checkbox component with v-model and array of items). Some recommend emitting modelValue:update instead of update:modelValue (https://github.com/vuejs/core/issues/2667#issuecomment-732886315). Etc.. Following worked for me after hour of trial and error on latest Vuejs3
Child
<template>
<div class="form-check noselect">
<input class="form-check-input" type="checkbox" :id="id" :checked="modelValue" #change="$emit('update:modelValue', $event.target.checked)" />
<label class="form-check-label" :for="id"><slot /></label>
</div>
</template>
<script>
import { v4 as uuidv4 } from "uuid";
export default {
inheritAttrs: false,
emits: ["update:modelValue"],
props: {
modelValue: {
type: Boolean,
required: true,
},
},
setup() {
return {
id: uuidv4(),
};
},
};
</script>
Parent:
<Checkbox v-model="someVariable">Is true?</Checkbox>
you can verify that it works but doing this in parent:
var someVariable= ref(false);
watch(someVariable, () => {
console.log(someVariable.value);
});
p.s. The other solution above does not work for me. Author recommends using value property. But in example he passes v-model attribute. So I don't know exactly how it's supposed to work.
You can achieve the behavior by using emits to keep data in sync and behave as default v-model behavior. Checkbox component:
<template>
<div>
<input
type="checkbox"
:checked="value"
#change="$emit('input', $event.target.checked)"
/>
{{ text }}
</div>
</template>
<script>
export default {
name: "inputcheckbox",
props: ["value", "text"],
};
</script>
And in the parent component you can have as many checkboxes you want.
<template>
<div id="app">
<maincontent :showContent="showContent" />
<inputcheckbox text="one" v-model="checkedOne" />
<inputcheckbox text="two" v-model="checkedTwo" />
</div>
</template>
Here is a vue 2 example but is applicable to vue 3 as well. Hope this was helpful. Sandbox with this behavior:
https://codesandbox.io/embed/confident-buck-kith5?fontsize=14&hidenavigation=1&theme=dark

Adding a component by clicking a button

Vue.component('component-a', {
template: '<h3>Hello world!</h3>'
})
new Vue({
el: "#app",
data: {
arr: []
},
methods: {
add(){
this.arr.push('component-a');
console.dir(this.arr)
}
}
})
<script src="https://cdnjs.cloudflare.com/ajax/libs/vue/2.5.17/vue.js"></script>
<div id="app">
<component-a></component-a>
<hr>
<button #click="add">Add a component</button>
<ul>
<li v-for="component in arr"> {{ component }} </li>
</ul>
</div>
I want to insert a component a lot of times to the page by clicking a butoon, but instead of this only a component`s name is inserted. How to add a component itself?
In your code the double curly braces do not reference the component itself but just the string you added with this.arr.push('component-a'); hence just the string being displayed.
If you would like this string to call the actual component you could use dynamic components.
Replacing {{ component }} with <component :is="component"/> would achieve the effect I think you're looking for.
However if you're only going to be adding one type of component I would consider adding the v-for to the component tag itself like so:
<component-a v-for="component in arr/>
Use the component element to render your component dynamically.
The usage is very simple: <component :is="yourComponentName"></component>
The ":is" property is required, it takes a string (or a component definition).
Vue will then take that provided string and tries to render that component. Of course the provided component needs to be registered first.
All you have to do is to add the component tag as a child element of your list tag:
<li v-for="component in arr">
<component :is="component"></component>
</li>
Vue.component('component-a', {
template: '<h3>Hello world!</h3>'
})
new Vue({
el: "#app",
data: {
arr: []
},
methods: {
add() {
this.arr.push('component-a');
console.dir(this.arr)
}
}
})
<script src="https://cdnjs.cloudflare.com/ajax/libs/vue/2.5.17/vue.js"></script>
<div id="app">
<component-a></component-a>
<hr>
<button #click="add">Add a component</button>
<ul>
<li v-for="component in arr">
<component :is="component"></component>
</li>
</ul>
</div>