How do I define a custom directive using composition API in Vue3? - vue.js

The documentation is quite clear on how to create a custom directive using app.directive() the "old way", but that does not take into account the composition API way of doing things.
What I expect is something like:
import MyDirective from "#/directives/MyDirective.vue" inside a component.
Use the directive in the component's template like <div my-directive></div>.
Preferably without having to add boilerplate like registering the directive in main.ts or anything of the sort.
However, I can't find any clear example or docs page describing this. Is this at all possible? How should I do it? Please include an example of the directive's definition itself.

Related

Is it possible to use NuxtLink to a Vue "component" in the components directory vs. a "page" route

I'm trying to create a form that I want to use modularly by linking to it from multiple page templates. Using just the straight vue-cli I would simply create a route to the file that has the form defined that I store in the "components" directory and then wrap a button linking to the form in a <router-link to="componentFormName"><btn></btn></router-link>. I'm having some difficulty determining how to do the equivalent in Nuxt. Any insights would be greatly appreciated. It seems the <NuxtLink></NuxtLink> only works with Vue files in the "Pages" directory.
You probably want to use dynamic components here: https://v2.vuejs.org/v2/guide/components-dynamic-async.html#keep-alive-with-Dynamic-Components
With something like this
<component :is="currentTabComponent"></component>
With currentTabComponent being one of the component to mount. You can mount a component depending of the current route with a relation between the URL and the component name too.
Also, Vue does not have any knowledge of "route", and everything is a component. Nothing really changes with a page because it is also a component at the end of the day. Or you could write one inside of it.
Maybe an example of your use-case would be helpful here.

How more correctly make Helper in VueJs?

I have some method to generate random hexademical color. It will be used in very few (3 or 5) parts of the project. So I want to separate it from main code into some kind of Helper or smth else, and include it when needed (not globally).
I have 2 working ways to do this:
Using mixins. What I don't like is that when you read the code, you can't separate your own methods from methods of mixin.
Using plugins. What I don't like with that is that you have to write import Vue from 'vue' + Vue.use(MyPlugin) every time in all files where you want to use it. After that, you can call it like this.$ColorHelper.getRandomHEX().
So, the question is about aesthetics visualization.
What is the best practices to do such things?
PS: project was created from template with webpack.
Our team decide use function import from files-helpers
For example:
import { getRandomColor, getBackgroundColor } from 'Global/helpers/colorHelper';
// .....
let color = getRandomColor();
What good:
Don't need use excess import + use as in plugins
Method visually stands out, what it not from this
What bad:
Cant see visually what the helper have method. But possible can fixed with aliases. We dont think yet
Vue plugins are global, you only have to call the Vue.use method once. Then they should work wherever you use that particular Vue instance.
In a default project setup you normally don't have multiple Vue instance so it should work globally.
From the docs:
Plugins usually add global-level functionality to Vue.
And:
Use plugins by calling the Vue.use() global method:
Vue.use(MyPlugin)
https://v2.vuejs.org/v2/guide/plugins.html

How to do two way binding in custom directives in Vue.js 2?

Hi I am looking for a solution for two way binding in Vue.js 2. I found a answer here about two way binding but it is in Vue.js 1. I tried to work it in Vue.js 1. But it didn't work. Can anyone help me here.
Why I want that?
A - I have a contenteditable div and a span tag inside which is shows a variable with v-html. But I want some functions to call when some edit happens. #change and #keyup don't work with span in vuejs 1. So I moved to custom directives.
To support something like this in vue2.0: as suggested by Evan You in forum here is to put these kind of functionality in a component and to reuse the same functionality on multiple components you can extract it into a shared mixin.
My suggestion is that the logic should be handled inside the component. In 2.0 v-model can work on components, e.g. https://github.com/vuejs/vue/blob/next/examples/select2/index.html
If you want to reuse the same logic on multiple components you can extract it into a shared mixin.

What is the difference between <compose> and <require> in Aurelia?

In learning the awesome Aurelia framework, I have learnt that you can use the following composition techniques however I am not sure what would be the difference.
<compose view="./nav-bar.html"></compose>
or
<require from="./nav-bar.html"></require>
Any clarification is appreciated.
<require> imports resources that you want to use in the view. It's conceptually similar to a require() JavaScript call in AMD or CommonJS module code (or an import statement in ES6 code). You would use <require> to import a custom element or custom attribute that you wanted to use in your view. You'll still need to explicitly render it like <nav-bar></nav-bar>.
<compose> renders the specified view.
We will use already created templates in our app and we need to use in the current app via require.
you can use css and javscript files also in require.
But from compose you can render your views by giving your view modal name.
You can see this link to have a better idea about compose.
http://patrickwalters.net/best-parts-of-aurelia-1-composing-custom-elements-templates/

Aurelia top level component without routing

Is it possible to add an Aurelia top level component without the router?
The goal is to create a component without the router since my application doesn't need any url based navigation.
From what I can tell Aurelia seems to take you down a path where components are instantiated via routing based on how the component is registered with the router.
Instead I would like to just add markup for the top level component on the main index.html page:
<my-component bind.current="'123456'"></my-component>
I would like define components without a router and only use the templating and data binding capabilities of Aurelia.
Is that possible?
Tried this in index.html (inside the body tag of the default project)
<require from='./dist/my-component'></require>
<my-component></my-component>
But it does not seem to pick it up. Ideally I would like to just define it in markup on a page served from the server since it would enable me to sett attributes dynamically on the elements
<my-component current.bind={{someServerGeneratedId}}></my-component>
In the above I would use a templating framework like mustache to dynamically render the Aurelia when the page is served from the server.
I could wrap the component in another "landing" component, but that makes it hard to benefit from setting things up with server generated bindings.
UPDATE:
Per Rob's response: https://github.com/aurelia/framework/issues/175#issuecomment-126965417
- He is expecting to add the ability to add a root component to the landing page in a future release. I understand there are ways to not use the router, but it still depends on pulling in a partial view during bootstrapping of the application. This does not use the router directly, but conceptually this is really just an implied/convention based client side nav. In the end there is a client side request to pull in the view, which means I can't generate the html dynamically from the initial server response.
Yes you can do this very easily without the router. Just remove the router configuration from your app.js and in app.html remove the router code there as well.
I think the issue you are running in to is that you are specifying the dist folder again in your index.html. You should just reference it like this -
<require from="my-component"></require>
<my-component current.bind="someServerGeneratedId"></my-component>
This will bind up correctly.
I guess you're missunderstanding the route concept here.
At the time of writing, Aurelia's index.html page is your initial page where you put your "loading" stuff and where Aurelia bootstraps the entire app.
So, you can't put a custom component directly on it, but that should not be a problem.
If you don't change any configuration on Aurelia, it will look for your app.html to bootstrap your app, and there you can have anything you want (routes or not, doesn't matter). So, you should put your component there, beside the other tags/components/etc you need.
I've made a plunker without any routing and with a custom component in the app.html, and something simulating what you need.
<template>
<require from='./my-component'></require>
<my-component current.bind="serverGeneratedID"></my-component>
</template>
http://plnkr.co/edit/mLb8Ym638b4V2e9LDp0A?p=preview
If you need anything else, comment here and I'll try to go further.