I'm having trouble trying to use the Vue.Draggable library. I would like to use a component inside my draggable while keeping the transition-group. It's working without the transition group but whenever Im adding the transition-group tag with the animation name its not working anymore. My components elements are not showing up and I'm having this error :
TypeError: Cannot set properties of null (setting '__draggable_context')
Here is my code :
<draggable :list="teams" item-key="idteam" tag="transition-group" :component-data="{name:'fade'}>
<template #item="{ element, index }">
<my-team :id="element.idteam" :name="element.teamName" :index="index">
</my-team
></template>
</draggable>
Any idea how could I make all work together ?
Thanks for your help
You need to add :animation="200"; only adding tag="transition-group" is not enough.
Related
Hi I'm trying to figure out how to use v-if on a iterated element which also uses v-for. I need to check if the current element has any of a series of classes, which are numbers.
so the classes of each article would be:
<article class="post-item post-guide 12 22 19 30 55">...
this is the HTML that renders all:
<article v-if="showIfHasClass" :class="'post-item post-guide ' + guide.categories.toString().replace(/,/g, ' ')"
v-for="(guide, index) in guides" :key="index">
<header>
<h1 class="post-title">
{{ guide.title.rendered}}
</h1>
</header>
</article>
I have tried with methods that check the class of all elements, that works, but i'm trying to use a clean Vue built-in solution with v-if without success, i'm not able to retrieve the class of this in a successful way.
Should showIfHasClass be a computed property? I have tried with that too... but it seems, I'm missing something along the way.
my data I have to check against is an array:
data:{
guides: [...]
selectedCategories: [1, 22, 33, 100, 30];
}
or maybe it is better to directly loop over the guides and check if they have the selectedCategory or not, then remove the element from the guides data array?
What is more effective?
Besides the option to create an additional filtered computed (effectively eliminating the need to use v-for and v-if on the same element), you also have a template level way of dealing with such edge-cases: the <template> tag.
The <template> tag allows you to use arbitrary template logic without actually rendering an extra element. Just remember that, because it doesn't render any element, you have to place the keys from the v-for on the actual elements, like this:
<template v-for="(guide, index) in guides">
<article v-if="isGuideVisible(guide)"
:key="index"
class="post-item post-guide"
:class="[guide.categories.toString().replace(/,/g, ' ')]">
<header>
<h1 v-text="guide.title.rendered" />
</header>
</article>
</template>
isGuideVisible should be a method returning whether the item is rendered, so you don't have to write that logic inside your markup. One advantage of this method is that you can follow your v-if element with a fallback v-else element, should you want to replace the missing items with fallback content. Just remember to also :key="index" the fallback element as well.
Apart from the above use-case, <template> tags come in handy when rendering additional wrapper elements is not an option (would result in invalid HTML markup) (i.e: table > tr > td relations or ol/ul > li relations).
It's mentioned here as "invisible wrapper", but it doesn't have a dedicated section in the docs.
Side note: since you haven't actually shown what's inside guide.categories, I can't advise on it, but there's probably a cleaner way to deal with it than .toString().replace(). If guide.categories is an array of strings, you could simply go: :class="guide.categories".
I think the most Vue way is to create a computed property with filtered items from selected categories, then use that in v-for loop (the idea is to move the business logic away from template).
computed: {
filteredItems(){
return this.guides.filter(e => this.selectedCategories.includes(e.category))
}
}
Also, as a note, it is not recommended to use v-if and v-for on the same element, as it may interfere with the rendering and ordering of loop elements. If you don't want to add another level of nesting, you can loop on a 'template' element.
<template v-for="item in items">
// Note the key is defined on real element, and not on template
<item-element v-if='condition' :key="item.key"></item-element>
</template>
Hello and thank you for reading my question.
I have an array of objects looking like this :
[{
id=1,
products= [a,b,c]
},
{
id=2,
products= [d,e,f]
}]
I want to display data in a v-data-table with two columns (id and products) and products items in a nested v-data-table.
So far I found that i should use template and v-slot but I don't find the right way to do it.
<v-data-table
item-key="id"
items={products}
>
<template v-slot="">
<v-data-table> ... </v-data-table>
</template>
</v-data-table>
Instead of the nested table I get
[object Object],[object Object]
How to use template v-slot in tsx files ?
And more generally, how to 'translate' vuetify js to tsx (documentation) ?
Thanks again
you have made a slot which is correct, but you need to tell vuetify which slot you want to access. To access the default <td> slot of all rows you can simply use v-slot:body="{ items }" and pass it the items, so you can create a view per column. (Available slots are listed here Vuetify doc, if you scroll down. Each component has them)
I have made a codepen that you can check out Codepen. As of translating it to tsx, I can't help you, since I haven't worked with it, but if you grasp the concept of how to do it on the vuetify part, you should be good!
I am using v-for for and then showing the components. is rendering fine but inner element is missing. I am unable to understand. You can see two columns are empty but in the console three are 5 components rendered but showing only 3 components. Tell what may be the problem. any help will be appreciated
<div v-for="(counterDate, index) in fulldate_array" >
<template v-if="shift[officer.oid]">
<shiftlayout v-for="(data,shiftKey) in shift[officer.oid][fulldate_array[index]]" :shift_data="data" :shiftKey="shiftKey" :date="singledate_array[index]" :fulldate="fulldate_array[index]" :width="shiftWidth"/>
</template>
</div>
Im trying to add a ripple effect to a card using angular material. The ripple effect works the way it supposed except that it expands the hight of the card when the effect is active.
How can I stop the card from expanding?
<mat-card mat-ripple>
<mat-card-content>This is content</mat-card-content>
</mat-card>
Stackblitz that demonstrates the behaviour
Add a class (i.e. last-child) to the last child of your mat-card (in your case mat-card-content) and define the following style:
.mat-card .last-child {
margin-bottom: 0;
}
The problem is that matRipple adds an zero-height element to the mat-card while Angular Material only removes the margin-bottom from the last child.
If you add the footer element (with or without content) you won't need additional CSS and this will lock the height when activating the ripple effect.
<mat-card mat-ripple>
<mat-card-content>This is content</mat-card-content>
<mat-card-footer></mat-card-footer>
</mat-card>
should be as easy as adding matRipple to the mat-card
<mat-card class="action-card" matRipple>
<mat-card-title>
{{content}}
</mat-card-title>
<mat-card-content>
desc
</mat-card-content>
</mat-card>
make sure you inject the MatRippleModule into your module.ts though, that threw me off for a while
Use a div -Tag inside of mat-card -Tag. This Fix my issue.
I have a list of components that I render using v-for. Not all the components are shown simultaneously. I page the the array of rendered components by using slice.
These components shouldn't be rerendered, as some of them have user inputted data and some of them do network related tasks.
I tried to use <keep-alive>. However, this renders only the first component.
<keep-alive>
<component :is="component.type" :key="component.id" v-for="component in components">
</keep-alive>
How do I keep a dynamic list of components alive?
<div v-for="comp in compList" :key="'container'+comp.keyId" >
<keep-alive>
<component :is="comp.type" :key="comp.keyId"></component>
</keep-alive>
</div>
this above works for me . Pushing elements to compList correctly creates new instances of their respective components. Moving an element's index within the array , maintaining key, does not call destroy/create and maintains state within each component
Tested the answer above in a fiddle and doesn't work. https://jsfiddle.net/z11fe07p/680/
<div v-for="component in myComponents" :key="component.id" >
<keep-alive>
<component :is="component.type"
:name="component.name">
</component>
</keep-alive>
</div>
Also i would avoid using vue reserved words such as components because there is a components key in the vue instance which tells what components the instance is using.
I read source code of Vue's <keep-alive>, and I created new Component which works very well with list.
package name is vue-keep-alive-global. Here is a link, https://www.npmjs.com/package/vue-keep-alive-global
How to use :
<KeepAliveGlobal>
<YourComponent
:key="uniqueKey"
/>
</KeepAliveGlobal>
With Array,
<template v-for="(item, index) of array">
<KeepAliveGlobal :key="`blah-blah-${index}`">
<YourComponent
:item="item"
:key="`your-component-${index}`"
/>
</KeepAliveGlobal>
</template>
KeepAliveGlobal will cache component by key.
There's note at Vue docs about your use case
Note, <keep-alive> is designed for the case where it has one direct
child component that is being toggled. It does not work if you have
v-for inside it. When there are multiple conditional children, as
above, ` requires that only one child is rendered at a
time.
https://v2.vuejs.org/v2/api/#keep-alive
Try v-once directive instead.
https://v2.vuejs.org/v2/api/#v-once