VueJS render once into an element - vue.js

Is it possible to just render once into an element?
Suppose I have a contenteditable div, and only want to render the first value, then stop rerendering as the model changes. Here only the initial value of variable will be rendered.
<div contenteditable="true"> {{variable}} </div>

Use v-once
<div contenteditable="true" v-once> {{variable}} </div>
You can also wrap it with a <span>:
<div contenteditable="true">
<span v-once> {{variable}} </span>
</div>
refs:
https://v2.vuejs.org/v2/guide/components.html#Cheap-Static-Components-with-v-once
https://v2.vuejs.org/v2/api/#v-once
Or another solution is simply clone the variable and just don't modify it, for example if you call it readOnlyVariable:
<div contenteditable="true"> {{readOnlyVariable}} </div>

Related

v-on:click not working - dynamically added html element

I am trying to get all images for a category using Vue
<div class="col-md-12 col-sm-2 p-2">
<a v-on:click="onCategoryManageImageClick($event)" data-target="#location-
category-images">
</span>
</a>
</div>
So the event onCategoryManageImageClick ($event) does not work, if I am adding a html block and then click on get image button.
this is index.js
methods:{
onImagesTabClick(){
this.$root.$emit('activated-tab:location-images');
},
onCategoriesTabClick(){
window.j1App.eventBus.$emit("j1-location-image-list:shown");
},
onCategoryManageImageClick: function(event) {console.log('working event..');
event.preventDefault();
window.j1App.eventBus.$emit("j1-location-category-image-
list:shown",event.currentTarget.id);
}
}
So basically it need to to work like we do in jQuery
$(document).on('click',function{
})
So it works either page load or if adding any new html element on DOM. same I want in Vue.
You cannot alter the Vue template outside of Vue. That won't work. Vue compiles the template once when starting up and adds the event listeners to the rendered elements. If you add elements afterwards, Vue will not know about them.
The correct way of doing this would be to add those new elements in Vue.
<div
class="col-md-12 col-sm-2 p-2"
v-for="item in items"
:key="item.id"
>
<a
v-on:click="onCategoryManageImageClick($event, item)"
data-target="#location-category-images"
>
</a>
</div>
See https://v2.vuejs.org/v2/guide/list.html for documentation. In this case you need the items array variable in data and add more array elements to it, if you need more links.
Try raplacing your a tag with p
<div class="col-md-12 col-sm-2 p-2">
<p v-on:click="onCategoryManageImageClick" data-target="#location-
category-images">
</p>
</div>

VueJS transition on computed values

I want to animate a block with posts that can be filtered.
Some filters trigger a computed method filteredPosts and they are assigned to a component liek that <block-article :posts="filteredPosts" />
In my <block-article> component I have something like that :
<template>
<div class="posts">
<div v-for="post in posts" :key="post.id"></div>
</div>
</template>
I want div .posts animate like a translation bottom/fade out on disappear and translation top/ fade in on appear.
I tried that :
<template>
<transition name="slide-fade">
<div class="posts">
<div v-for="post in posts" :key="post.id"></div>
</div>
</transition>
</template>
with corresponding css classes but it doesn't work.
I tried that :
<template>
<div class="posts">
<transition-group name="slide-fade">
<div v-for="post in posts" :key="post.id"></div>
</transition-group>
</div>
</template>
but my class .posts is a grid and here I lost the grid behavior.
THE AIM is to animate the entire div .posts rather than each elements of the v-for.
Any idea ?
Thanks all,
I finally achieve this with :
<transition name="slide-fade">
<div :key="posts.length" class="posts"></div>
</transition>
Nothe the :key="posts.length"
The problem is when posts.length doesn't change but it works in a lots of case. I will search how to fix this exception.
If you animate entire div, you should use transition, but in this case all inner elements not animated. If you want to animate all inner elements. You should use transition-group
In your case I think, need use all this method with build-in tag attribute.
Becouse in dock you can read
https://v2.vuejs.org/v2/guide/transitions.html
Unlike transition, it renders an actual element: a span by default. You can change the element that’s rendered with the tag attribute.
So you can write like this(its not full code, you must add name, key and other attrs)
<transition>
<transition-group tag="div" class="posts">
<div v-for="post in posts"></div>
</transition-group>
</transition>

preventing Vue from aggresively reusing dom-elements

Condider the following snippet:
<template v-if="tryIsMobile" >
<div class='device device-mobile-portrait' :class="deviceClass">
<div class="device-scroller-container">
<div class='device-scroller'>
<img id='tryit-img-mobile' :src="srcUrlMobile" v-on:load="onImgLoad" v-on:error="onImgError"/>
</div>
</div>
</div>
</template>
<template v-else>
<div class='device device-tablet-landscape' :class="deviceClass" >
<div class="device-scroller-container">
<div class='device-scroller'>
<img id='tryit-img-tablet' :src="srcUrlTablet" v-on:load="onImgLoad" v-on:error="onImgError"/>
</div>
</div>
</div>
</template>
This code conditionally renders one of the two images. Some user action results in the actual shown image to be toggled.
What I'm seeing is the following: When toggling from say, tryit-img-mobile to tryit-img-tablet, the image loaded as part of tryit-img-mobile will get displayed with different dimensions instantly. However, during the time the image loads it's new source :src="srcUrlTablet", the image with src :src="srcUrlMobile" still displays.
This is probably due to Vue using the same img-tag for both the templates. How can I prevent Vue from doing this, and instead use seperate img-tags?
In cases such as this, Vue uses a special key attribute that tells it not to reuse the same element. Give each element this attribute with a unique value, and Vue will no longer reuse the same element:
<div v-if="tryIsMobile"
class="device device-mobile-portrait"
:class="deviceClass"
key="mobile"
>
...
</div>
<div v-else
class="device device-tablet-landscape"
:class="deviceClass"
key="tablet"
>
...
</div>

In Aurelia, can a slot be used in a repeat.for binding?

I'd like to create a custom element that loops through an array and applies the to each item in the array. For example, the view template of the custom element would contain something like:
<div repeat.for="i of items">
<div with.bind="i">
<slot></slot>
</div>
</div>
When I remove the repeat.for and with.bind attributes, the slot displays a single time. Is there a way to make it repeat for each item in the list?
No, you cannot use slots with repeat.for or bind today. To do this you have to use replaceable parts. For example:
<div repeat.for="i of items">
<div with.bind="i">
<template replaceable part="content"></template>
</div>
</div>
Usage:
<my-component>
<template replace-part="content">Some Content - ${somePropertyOfI}</template>
</my-component>
Runnable example: https://gist.run/?id=29aa1c1199f080c9ba0e72845044799b

Vue named slots do not work when wrapped

I have a responsive-menu component which I want to use named slots inside of this up my template markup:
<template>
<div class="responsive-menu">
<div class="menu-header">
<slot name="header"></slot>
</div>
</div>
</template>
Whenever I try my named slot like this it work perfectly fine:
<responsive-menu>
<h3 slot="header">Responsive menu header</h3>
</responsive-menu>
However as soon as I wrap it with a class nothing shows up anymore.
<responsive-menu>
<div class="container">
<h3 slot="header">Responsive menu header</h3>
</div>
</responsive-menu>
What is going on here? Shouldn't I just be able to wrap the named component? Which does it appear that my named slots need to be direct children of my Vue component?
It does not work because your "wrapped slot" isn't direct child of responsive-menu tag.
try something like that:
<responsive-menu>
<div class="container" slot="header">
<h3>Responsive menu header</h3>
</div>
</responsive-menu>
jsfiddle
It works with Vue >= 2.6. Just upgrade vue and vue-template-compiler.