Hoist slot content up one level - vue.js

I hope someone can help me out with this problem! I'm using a Table component from PrimeVue, and I'm looking to create a wrapper component with a slot for content. The problem is, the component will only recognize content directly within its default slot. Nothing else is recognized.
Code:
<template>
<DataTable :value="data">
<!-- These components are recognized -->
<Column v-for="col in cols" :key="col.field" :field="col.field" :header="col.header" />
<slot name="override" :cols="cols">
<!-- These components are not -->
<Column v-for="col in cols" :key="col.field" :field="col.field" :header="col.header" />
</slot>
</DataTable>
</template>
<script>
export default {
data() {
return {
data: // Array of data here,
cols: // Array of cols here
}
}
}
</script>
I checked their implementation, DataTable only looks in $slots.default().children for content. Since the content in <slot name="override"> will show up as something along the lines of $slots.default().children.children, they are not recognized. Is there a way for me to hoist or inject any content (including the default content if possible) from the slot into its parent so the content appears in $slots.default().children?

This template:
<template>
<slot name="heading">
<h1>Default heading</h1>
<h2>Default subheading</h2>
</slot>
</template>
...is effectively the same as conditionally rendering the <slot> with v-if="$slots.heading" (which is only truthy when the heading slot is actually passed in) and moving its inner contents to a v-else block:
<template>
<slot v-if="$slots.heading" name="heading">
</slot>
<template v-else>
<h1>Default Heading</h1>
<h2>Default subheading</h2>
</template>
</template>
So, you can use v-if="$slots.override" to conditionally render the <slot>, and move its contents (i.e., the <Column>s) into a v-else block:
<DataTable :value="data">
<slot v-if="$slots.override" name="override" :cols="cols" />
<Column v-else v-for="col in cols" :key="col.field" :field="col.field" :header="col.header" />
</DataTable>
demo

Related

Nuxt2/Vue2, checking a $slots sometime fails on rerender

I have a strange issue on a Nuxt2/Vue2 project.
I have a component with a slot named "image" conditionally displayed. The condition only checks "$slots.image". It works properly on the first render of the component, but if it have to rerender, sometimes the condition fail.
I fixed this issue by modifying the condition to checks also "$scopedSlots.image". But I don't understand what is happening.
Does someone can explain to me what is happening here ?
Here is the parent where my component is imported:
<template>
<div>
<nav-pane>
<template #subheader>
<nav-pane-sub-header>
<template #image>
<avatar />
</template>
</nav-pane-sub-header>
</template>
</nav-pane>
</div>
</template>
Here is my component 'NavPaneSubHeader' with the buggy condition:
<template>
<div>
<div>
<i v-if="icon" />
<slot v-else-if="$slots.image"/>
</div>
<slot />
</div>
</template>
Works fine with :
<slot v-else-if="$scopedSlots.image || $slots.image" />

Slot on Vuetify.js custom component

I have a component which renders a standard .
I would like to use slots from my component, I would like to write something like:
<MyComponent>
<header>
Titolo
</header>
<body>
my component body
</body>
</MyComponent>
then final component should be:
<v-dialog>
<h1>
// header slot content
</h1>
// body slot content
</v-dialog>
how can I do this? This only works with <slot> but not with named slot.
To use multiple slots you can use the following syntax:
<MyComponent>
<template v-slot:header>
Titolo
</template>
<template v-slot:body>
<p>my component body</p>
</template>
</MyComponent>
So you can pass some HTML in the template blocks and it will render in the component.
MyComponent.vue has the next content:
<template>
<v-dialog>
<h1>
<slot name="header"></slot>
</h1>
<slot name="body"></slot>
</v-dialog>
</template>
You can define names for your slots in your custom component by using the name attribute available for the <slot> element, e.g. <slot name="header">. If you don't define a name for the slot, its name will just be default. See the Vue.js slots documentation here: https://v2.vuejs.org/v2/guide/components-slots.html
Also, I made a simple usage example that you can check out here: https://codesandbox.io/s/unruffled-mopsa-f47hm?file=/src/App.vue
So in your case, your custom component could look something like this:
<v-dialog>
<slot name="header" />
<slot name="body" />
</v-dialog>
And to use it in the parent component, you could have:
<MyComponent>
<template v-slot:header>
Titolo
</template>
<template v-slot:body>
<p>my component body</p>
</template>
</MyComponent>

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>

Passing value from parent to child using slot probably

I probably don't understand how it should be done. I spent a few hours to achieve this functionality but with no luck. Here is what I have:
Child
<template>
<div>
Data from dialog: {{aaa}}
</div>
</template>
<script>
export default {
name: 'frm',
props: [
'aaa'
]
}
</script>
Parent:
<template>
<div>
<slot :aaa="some"></slot>
</div>
</template>
<script>
export default {
name: 'dlg',
data: () => ({
some: 'data from dialog'
})
}
</script>
View:
<template>
<div>
<dlg>
<frm></frm>
</dlg>
</div>
</template>
<script>
import Dialog from '#/components/dialog.vue'
import Frm from '#/components/frm.vue'
export default {
name: "View",
components: {
'dlg': Dialog,
'frm': Frm
}
};
</script>
Edit: Real code
dialog-template:
<template>
<v-dialog
v-model="internal.dialogOpened"
>
<!-- ... -->
<slot :aaa="'dsada'"></slot>
</v-dialog>
</template>
details-task-dialog:
<template>
<dlg-template large position='right' :onclose="close" :load="loadRetry">
<task-details-form /> <!-- just regular component in which I want to get value passed through slot in dialog-template -->
</dlg-template>
</template>
<script>
import DlgTemplate from '#/components/site/dialogs/dialog-template.vue'
export default {
// ...
components: {
'dlg-template': DlgTemplate,
'task-details-form': DetailsForm,
},
I want to avoid passing prop in View but I don't know how :/ I've read about 'slot-scope' unfortunately with no success. How to achieve such functionality?
Edit: real code
Based on your real world code, you were only missing the attachment of the scope, see below.
dialog-template:
<template>
<v-dialog v-model="internal.dialogOpened">
<!-- ... -->
<slot :aaa="'dsada'"></slot>
</v-dialog>
</template>
details-task-dialog:
<template>
<dlg-template large position='right' :onclose="close" :load="loadRetry">
<task-details-form v-slot="{ aaa }">
<!-- you can use the var `aaa` here -->
</task-details-form>
</dlg-template>
</template>
I'd still wager if you want to use aaa inside task-details-form component you have to pass it down as a prop. But it looks wierd to me, because I'm unsure of the execution order right now (v-slot vs v-bind), but try it like this:
<template>
<dlg-template large position='right' :onclose="close" :load="loadRetry">
<task-details-form v-slot="{ aaa }" :your-a-prop-name="aaa" />
</dlg-template>
</template>
Edit 2: after testing
v-bind shorthand is not working on <slot>:
dialog-template:
<template>
<v-dialog v-model="internal.dialogOpened">
<!-- ... -->
<slot v-bind:aaa="'dsada'"></slot>
</v-dialog>
</template>
details-task-dialog:
<template>
<dlg-template large position='right' :onclose="close" :load="loadRetry">
<template v-slot="{ aaa }"> <!-- has to preceed v-bind -->
<task-details-form :propertyOnComponent="aaa" /> <!-- now you cand bind it -->
</template>
</dlg-template>
</template>
Original:
I think you misunderstood slots. Check the docs:
That slot has access to the same instance properties (i.e. the same “scope”) as the rest of the template. The slot does not have access to child’s scope.
Slots
So you could do that, but then your code becomes:
<template>
<div>
<dlg>
<frm>
<child :aaa=“dialogData” />
</frm>
</dlg>
</div>
</template>
Frm:
<template>
<div>
From component
<slot></slot>
</div>
</template>
If you would define a slot on frm as you are suggesting, you would be able to fill that slot with a specific template and you can receive(!) the scope for that slot.
The deprecated slot-scope which you mentioned would provide you with a bound context from the child to be exposed in your overriding slot in the parent, that’s the opposite of what you want.
Just out of curiosity, why not send down the dialog data to the form as a property? That’s exactly what it’s for.

Vuejs nested slots: how to pass slot to grandchild

I use different vuetify components, for example v-menu. It has a template like this:
<v-menu>
<a slot="activator">menu</a>
<v-list>
<v-list-tile>Menu Entry 1</v-list-tile>
<v-list-tile>Menu Entry 2</v-list-tile>
</v-list>
</v-menu>
Suppose I want to add another wrapper around it. That is my special menu component that has some predefined menu options. And I want it to has an activator slot as well. And the last should be somehow assigned to the original v-menu activator slot. Is it possible?
Example:
// index.vue:
<template>
<my-special-menu>
<button>My special menu trigger</button>
</my-special-menu>
</template>
// MySpecialMenu.vue
<template>
<v-menu>
<slot slot="activator"/> <-- I don't know how to write this line
<v-list>...</v-list>
</v-menu>
</template>
<slot slot="activator"> is an incorrect equation. The goal is to pull the content from the parent (that is <button>..</button> in the example), and use it as slot="activator" in v-menu.
I can write it like this:
<v-menu>
<a slot="activator"><slot/></a>
...
</v-menu>
But this case the result template will be:
<div class="v-menu__activator">
<a>
<button>My special menu trigger</button>
</a>
</div>
That's not exactly what I want. Is it possible to get rid off <a> wrapper here?
Update:
We can use a construction like <template slot="activator"><slot name="activator"/></template> to throw some slot to a grand child. But what if we have multiple slots and we want to proxy them all? That's like inheritAttrs and v-bind="$attrs" for slots. Is it currently possible?
For example, there's <v-autocomplete> component in vuetify that has append, prepend, label, no-data, progress, item, selection etc slots. I write some wrapper component around this, it currently looks like:
<template>
<v-autocomplete ..>
<template slot="append"><slot name="append"/></template>
<template slot="prepend"><slot name="prepend"/></template>
<template slot="label"><slot name="label"/></template>
...
<template slot="item" slot-scope="props"><slot name="item" v-bind="props"/></template>
</v-autocomplete>
</template>
Is it possible to avoid all slots enumeration here?
If you put the slot attribute on a html element, that html element is passed to the child component to fill the slot with that name. If you don't want to pass along a html element, you can use slot on a template tag within your component. A template tag groups elements, but does not render to a html element, which is perfect here. You can use template tags also for other things, such as to group elements in a v-if for example, or to repeat multiple elements with a v-for.
// App.vue
<template>
<div id="app">
<test>
<template slot="activator">
Click <b>me</b>!
</template>
</test>
</div>
</template>
// Test.vue
<template>
<div class="wrapper">
<grand-child>
<template slot="activator">
<slot name="activator"></slot>
</template>
</grand-child>
This is some text
</div>
</template>
// GrandChild.vue
<template>
<div>
<a href="#" #click="toggle = !toggle">
<slot name="activator">Default</slot>
</a>
<div v-if="toggle">This appears and disappears</div>
</div>
</template>
Edit: If you want to do this for arbitrary slots, this is also possible. this.$slots contains the slots and their content, so with something like the following, you can pass the slot content to a slot with the same name:
<grand-child>
<template v-for="(_, slot) in $slots">
<template :slot="slot">
<slot :name="slot"></slot>
</template>
</template>
</grand-child>
For completeness sake, scoped slots can be accessed through $scopedSlots and be propagated like so:
<grand-child>
<template v-for="(_, slot) in $scopedSlots" v-slot:[slot]="props">
<slot :name="slot" v-bind="props" />
</template>
</grand-child>
source and comment
I had EsLint errors because of the depreciated :slot and $scopedSlots attributes.
So I combined both of #Sumurai8 answers like this and it works great:
<template v-for="(_, slot) in $slots" v-slot:[slot]>
<slot :name="slot"></slot>
</template>
If you have both named and unnamed slots with props:
Vue 3
<template v-for="(_, name) in $slots" #[name]="slotData">
<slot :name="name" v-bind="slotData || {}" />
</template>
Typescript version
<template v-for="(_, name) in ($slots as {})" #[name]="slotData">
<slot :name="name" v-bind="slotData || {}" />
</template>