How to access slot props from the component used inside the slot? - vue.js

so everything i can find about scoped slots and passing props dont work for my specific situation:
i have following component order:
Home/List/ListItem
now i desided to replace the ListItem with a slot and because i use the List in a other Component too, but in there i need the ListOptionsItem.
in my home component i did this:
<list
class="mapkeyList"
:content="displayList"
:filterbar="true"
#handleSelection="addSelection"
#delete="deleteElement"
#editItem="editItem"
header="Mapkeys"
:key="mapkeyListKey"
>
<list-item>
</list-item>
</list>
in my List component i have this:
<template>
<div>
<h2 v-if="header">{{header}}</h2>
<div class="listContainer" v-if="showedContent.length > 0">
<div v-for=" (item, index) in showedContent" :key="index">
<slot
:item="item"
:index="index"
:dragable="dragableItems"
#auswahl="auswahlHandle"
#deleteElement="deleteElement"
#editItem="editItem"
:dontShowButtons="dontShowButtons"
#dragStart="handleOverDragStart"
:dragItem="dragItem"
#position="$emit('emitPosition',item)"
:deaktivierbar="deaktivierbar"
>
</slot >
</div>
finaly the listItem and the listOptionsItem need to access this props in the slot:
listItem:
<template>
<div class= "flexSpaceBetween" #click="$emit('auswahl',item)">
<div class="textFett">
{{item[0]}}
</div>
<div>
{{item[1]}}
</div>
</div>
i dont want to write all the neccessarry code in the home component because the listOptionsItem does need more informations and more space to write code.
my goal was it to define in the Home component that i want the list to use the listItem component and in the Options component the list should use the listItemOptions component. in the future there could be added new listItem versions.

Any component used inside scoped slot has no implicit access to the slot props. To make them available inside the component, you must pass it down to that component as props explicitly...
<list
class="mapkeyList"
:content="displayList"
:key="mapkeyListKey">
<template v-slot:default="{ item }">
<list-item :item="item">
</list-item>
</template>
</list>
If you have a lot of props/events you want to pass along, the ability of both v-bind and v-on to take an object as an argument is very useful because you can pass all the data and event handlers at the same time:
// List component
<template>
<div>
<h2 v-if="header">{{header}}</h2>
<div class="listContainer" v-if="showedContent.length > 0">
<div v-for=" (item, index) in showedContent" :key="index">
<slot :props="slotProps" :on="slotEventsHandlers"
</slot >
</div>
</div>
</div>
</template>
<script>
export default {
computed: {
slotProps() {
return {
item: this.item,
dragable: this.dragableItems
}
},
slotEventsHandlers() {
return {
deleteElement: this.deleteElement,
dragStart: this.handleOverDragStart
}
}
}
}
</script>
And use it in parent:
<list
class="mapkeyList"
:content="displayList"
:key="mapkeyListKey">
<template v-slot:default="{ props, on }">
<list-item v-bind="props" v-on="on">
</list-item>
</template>
</list>

Related

how to create button group component in vue

I am trying to create button-group component in vue using typescript:
<template>
<slot>
<CButton
v-for="(vnode, index) in $slots.default || []"
:key="index"
:class="[
{ 'first-index': index === 0 },
{ 'last-index': index === ($slots.default ? $slots.default.length : 0) - 1 },
]"
>
{{ index }}
{{ vnode }}
</CButton>
</slot>
</div>
</template>
Here index comes null but I am expecting it turns as much as button I added.
Here is the parent:
<ButtonGroup>
<CustomButton>1</CustomButton>
<CustomButton>2</CustomButton>
<CustomButton>3</CustomButton>
</ButtonGroup>
Here is how you need to use slots in Vue:
<!-- ButtonGroup -->
<template>
<div class="button-group">
<slot></slot> <!-- Define the default slot -->
</div>
</template>
<template>
<ButtonGroup>
<!-- Fill in the slot with whatever you want -->
<CustomButton class="my-class">Test</CustomButton>
<button class="regular-button">Normal</button>
<CustomButton />
</div>
</template>
Example playground

Vue: can slot data go back to parent to pass down a prop?

I have my parent component using a MyGrid component and slotting in data. Inside MyGrid, I am checking the item type and if it is a certain type, I am giving it a class typeSquare.
In the interest of keeping MyGrid "dumb", is there a way I can check the type and then have MyGrid pass in a prop for the class?
Parent
<MyGrid
:items="items"
columnGap="12"
rowGap="14"
>
<template v-slot="slotProps">
<Cover
v-if="slotProps.typename === 'NewOne'"
:project="slotProps.item.data"
/>
<Cover2 v-else-if="slotProps.typename != 'NewOne'" :project="slotProps.item.data"/>
</template>
</MyGrid>
MyGrid.vue
<template>
<div :class="$style.root">
<div :class="$style.gridContainer">
<template v-for="(item, index) in items">
<div
:key="index"
:class="[{ [$style.gridItem]: true }, { [$style.typeSquare]: item.typename === 'NewOne' }]"
:style="{
padding: `${columnGap}px ${rowGap}px`,
}"
>
<slot :item="item"></slot>
</div>
</template>
</div>
</div>
</template>
If your goal is to only pass items that are of a certain criteria you can filter them out using computed properties. In your script add computed object like so
computed:{
filteredItems(){
return this.items.filter(item=>item.typename === 'NewOne')
}
},
And after in your template you can pass computed property instead of the whole list
<MyGrid
:items="filteredItems"
columnGap="12"
rowGap="14"
>

Executing js on slot

I'm a beginner in web development and I'm trying to help out friends restarting an old game. I'm in charge of the tooltip component but I hit a wall...
There are many Vue components and in a lot of them I want to call a child component named Tooltip, I'm using vue-tippy for easy configuration. This is the component:
<template>
<tippy class="tippy-tooltip">
<slot name='tooltip-trigger'></slot>
<template #content>
<slot name='tooltip-content'>
</slot>
</template>
</tippy>
</template>
<script>
import { formatText } from "#/utils/formatText";
export default {
name: "Tooltip",
methods:{
formatContent(value) {
if (! value) return '';
return formatText(value.toString());
}
},
}
</script>
In one of the other components I try to use the tooltip:
<template>
<a class="action-button" href="#">
<Tooltip>
<template #tooltip-trigger>
<span v-if="action.movementPointCost > 0">{{ action.movementPointCost }}<img src="#/assets/images/pm.png" alt="mp"></span>
<span v-else-if="action.actionPointCost > 0">{{ action.actionPointCost }}<img src="#/assets/images/pa.png" alt="ap"></span>
<span v-if="action.canExecute">{{ action.name }}</span>
<span v-else><s>{{ action.name }}</s></span>
<span v-if="action.successRate < 100" class="success-rate"> ({{ action.successRate }}%)</span>
</template>
<template #tooltip-content>
<h1>{{action.name}}</h1>
<p>{{action.description}}</p>
</template>
</Tooltip>
</a>
</template>
<script>
import Tooltip from "#/components/Utils/ToolTip";
export default {
props: {
action: Object
},
components: {Tooltip}
};
</script>
From here everything is fine, the tooltip is correctly displayed with the proper content.
The thing is, the text in the {{ named.description }} needs to be formatted with the formatContent content. I know I can use the props, the components would look like that:
Tooltip.vue:
<template>
<tippy class="tippy-tooltip">
<slot name='tooltip-trigger'></slot>
<template #content>
<h1 v-html="formatContent(title)" />
<p v-html="formatContent(content)"/>
</template>
</tippy>
</template>
<script>
import { formatText } from "#/utils/formatText";
export default {
name: "Tooltip",
methods:{
formatContent(value) {
if (! value) return '';
return formatText(value.toString());
}
},
props: {
title: {
type: String,
required: true
},
content: {
type: Array,
required: true
}
}
}
</script>
Parent.vue:
<template>
<a class="action-button" href="#">
<Tooltip :title="action.name" :content="action.description">
<template v-slot:tooltip-trigger>
<span v-if="action.movementPointCost > 0">{{ action.movementPointCost }}<img src="#/assets/images/pm.png" alt="mp"></span>
<span v-else-if="action.actionPointCost > 0">{{ action.actionPointCost }}<img src="#/assets/images/pa.png" alt="ap"></span>
<span v-if="action.canExecute">{{ action.name }}</span>
<span v-else><s>{{ action.name }}</s></span>
<span v-if="action.successRate < 100" class="success-rate"> ({{ action.successRate }}%)</span>
</template>
</Tooltip>
</a>
</template>
<script>
import Tooltip from "#/components/Utils/ToolTip";
export default {
props: {
action: Object
},
components: {Tooltip}
};
</script>
But I need to use a slot in the tooltip component because we'll have some "extensive" lists with v-for.
Is there a way to pass the data from a slot into a JS function?
If I understand you correctly, you're looking for scoped slots here.
These will allow you to pass information (including methods) from child components (the components with <slot> elements) back to the parents (the component(s) filling those slots), allowing parents to use chosen information directly in the slotted-in content.
In this case, we can give parents access to formatContent(), which will allow them to pass in content that uses it directly. This allows us to keep the flexibility of slots, with the data passing of props.
To add this to your example, we add some "scope" to your content slot in Tooltip.vue. This just means we one or more attributes to your <slot> element, in this case, formatContent:
<!-- Tooltip.vue -->
<template>
<tippy class="tippy-tooltip">
<slot name='tooltip-trigger'></slot>
<template #content>
<!-- Attributes we add or bind to this slot (eg. formatContent) -->
<!-- become available to components using the slot -->
<slot name='tooltip-content' :formatContent="formatContent"></slot>
</template>
</tippy>
</template>
<script>
import { formatText } from "#/utils/formatText";
export default {
name: "Tooltip",
methods: {
formatContent(value) {
// Rewrote as a ternary, but keep what you're comfortable with
return !value ? '' : formatText(value.toString());
}
},
}
</script>
Now that we've added some scope to the slot, parents filling the slot with content can use it by invoking a slot's "scope":
<!-- Parent.vue -->
<template>
<a class="action-button" href="#">
<Tooltip>
. . .
<template #tooltip-content="{ formatContent }">
<!-- Elements in this slot now have access to 'formatContent' -->
<h1>{{ formatContent(action.name) }}</h1>
<p>{{ formatContent(action.description) }}</p>
</template>
</Tooltip>
</a>
</template>
. . .
Sidenote: I prefer to use the destructured syntax for slot scope, because I feel it's clearer, and you only have to expose what you're actually using:
<template #tooltip-content="{ formatContent }">
But you can also use a variable name here if your prefer, which will become an object which has all your slot content as properties. Eg.:
<template #tooltip-content="slotProps">
<!-- 'formatContent' is now a property of 'slotProps' -->
<h1>{{ slotProps.formatContent(action.name) }}</h1>
<p>{{ slotProps.formatContent(action.description) }}</p>
</template>
If you still need the v-html rendering, you can still do that in the slot:
<template #tooltip-content="{ formatContent }">
<h1 v-html="formatContent(title)" />
<p v-html="formatContent(content)"/>
</template>

My dynamic component (layout) doesn't work with named slots in vuejs

I have problems to combine dynamic generated layouts with named slots.
To define my layouts I'm using "component :is"
//app.vue
<template>
<component :is="layout">
<router-view />
</component>
</template>
<script>
computed: {
layout() {
const layout = this.$route.meta.layout || 'default'
return () => import(`#/app/layouts/${layout}.vue`)
}
},
</script>
//layouts/default.vue
<template>
<div>
<div>
<slot name="header" />
</div>
<div>
<div>
<slot name="sidebar" />
</div>
<div>
<slot name="default"/>
</div>
</div>
</div>
</template>
// views/page.vue
<template>
<div>
<template #header>
<h1>Primitives</h1>
</template>
<template #sidebar>
<ul>
<li v-for="primitive in sections.sections" :key="primitive">
<router-link :to="`/primitives/${primitive}`">{{primitive}}</router-link>
</li>
</ul>
</template>
<template #default>
<router-view :key="$router.path" />
</template>
</div>
</template>
But now I get this error inside my code
'v-slot' directive must be owned by a custom element, but 'div' is not.
and console displays this error
<\template v-slot> can only appear at the root level inside the receiving component
If I remove the main div I get the error
The template root requires exactly one element.
What I'm doing wrong?
This is not easy to explain so please cope with me...
I really understand what you are trying to do but unfortunately it is not possible in Vue.
Reason for that is slots are more template compiler feature than runtime feature of Vue. What I mean by that ? When Vue template compiler sees something like <template #header>, it will take the inner content and compile it into a function returning virtual DOM elements. This function must be passed to some component which can call it and include the result in it's own virtual DOM it is generating. To do that template compiler needs to know to what component it should pass the function (that is the real meaning of 'v-slot' directive must be owned by a custom element, but 'div' is not. error message...ie compiler is "looking" for a component to pass the slot content to...)
But you are trying to use the slots as if they were "discoverable" at runtime. For your code to work the dynamic layout component must at runtime somehow discover that it's child (also dynamic thanks to <router-view />) has some slot content it can use. And this is not how slots work in Vue. You can pass the slot content your component receives from parent to a child components but do not expect that parent component (layout in this case) can "discover" slot content defined in it's child components...
Unfortunately only solution for your problem is to import the layout component in every "page" and use it as a root element in the template. You can use mixins to reduce code duplication (to define layout computed)
#/mixins/withLayout.js
export default = {
computed: {
layout() {
const layout = this.$route.meta.layout || 'default'
return () => import(`#/app/layouts/${layout}.vue`)
}
}
}
views/page.vue
<template>
<component :is="layout">
<template #header>
<h1>Primitives</h1>
</template>
<template #sidebar>
<ul>
<li v-for="primitive in sections.sections" :key="primitive">
<router-link :to="`/primitives/${primitive}`">{{primitive}}</router-link>
</li>
</ul>
</template>
<template #default>
<router-view :key="$router.path" />
</template>
</component>
</template>
<script>
import withLayout from '#/mixins/withLayout'
export default {
mixins: [withLayout]
}
</script>

Vue listen and handle from Emits from elements inside slots

Basically I have Parent, child, child-of-child component while child component have 2 named slots and child-of-child component have 1 slot so template ends up like this:
Structure of the components
<parent>
<child>
<child-of-child></child-of-child>
</child>
</parent>
Parent tempalte:
<template>
<div>
<labeled-menu>
<label slot="label">
Open Menu
</label>
<ul slot="menu">
<li v-for="i in [1,2,3,4,5,6,7]" #click="$emit('test', `${i} li is clicked`)">List {{i}}</li>
</ul>
</labeled-menu>
</div>
</template>
Child Template with 2 named slots while the 'menu' slot is passed as slot of the child-of-child component:
<template>
<div>
<div #click="show">
<slot name="label">
</slot>
</div>
<v-dialog :class="getMenuSize" :is-active="isActive" #hide="hide" :position="position">
<slot name="menu">
</slot>
</v-dialog>
</div>
</template>
child-of-child component
<template>
<div>
<div class="dialog-container">
<div class="dialog-header">
</div>
<div class="dialog-body">
<slot>
//here the ul and lis are basically displayed
</slot>
</div>
</div>
</div>
</template>
I didn't get your problem but if you want a global emitter handler a common pattern is to create a singleton of a vue instance and import it when you need it.
src/bus/index.js
import Vue from 'vue'
const bus = new Vue()
export default bus
src/components/Whatever.vue
import bus from 'src/bus'
// And then in your functions
bus.$on(...)
bus.$emit(...)
bus.$off(...)
If you're looking for a more structured event system, you should take a look at the store pattern with vuex.