How to use vue3/vue router correctly? - vue.js

I had some problems trying out the vue3.
router is my custom.
import router from './router'
when i write
createApp(App).use(Antd,VueAxios,axios,qs,router).mount('#app')
The page does not load the correct page.Vue Router Looks like not working
but when i write
createApp(App).use(router,Antd,VueAxios,axios,qs).mount('#app')
it's working!
So why?
code:https://github.com/fangminghui/app_h5

app.use or createApp(App).use doesn't accept multiple plugin as parameters, it accepts only the plugin and its options if there's options :
createApp(App).use(thePlugin,options)
if you want to use multiple ones you should chain multiple .use like :
createApp(App).use(qs).use(router).use(VueAxios).use(Antd).mount('#app')

Related

How to extend a component in Vue 3?

The import is working just fine in case I try to use the component from element-plus directly.
What I'm trying to do though, is to extend a component from element-plus library (it uses the composition api from Vue 3) and add some additional properties to my component and methods.
In Vue 2 it would look something like this:
export default {
extends: SomeComponent
}
In Vue 3 this seems to not be working anymore.
I've read about defineComponent but so far, without success implementing it.
Can someone shed me some lights? Thanks.
In order to extend a component that uses Composition API whereas another still uses Options API, we need to also do the setup, such as:
export default { extends: SomeComponent, setup: SomeComponent.setup }

Gridsome: How to add Vue.use(MyPlugin) for a single page only?

I have added ReCaptcha plugin using Vue.use(ReCaptcha, {some options}) in Gridsome main.js which is displaying on all pages.
How to add plugin for a particular page only in gridsome?
I've never used ReCaptcha or Gridsome before, but generally, if you install a plugin using npm, then the simplest way to use it on a single page would be to import the plugin to the specific component rendered on the route you want to use it on. i.e
/* === MyComponent.vue === */
<script>
import plugin from 'packageName';
// or
import { pluginExport } from 'packageName';
export Default{
// You can then use the plugin/pluginExport here
}
From there you should be able to use the package in that specific component as you normally would if you implemented it app-wide with Vue.use. In some cases, depending on how the plugin is meant to be used, you may need to register the imported plugin Module as a child component in the components object. Like this vuejs QR Code generator for example.

How to use vue-router in Vuex module Actions?

I want to do this.$router.push(path) inside module file of vuex.
As this is not defined there, how could I perform this.
Just import the router and you'll be able to use it, like this:
import router from 'path/to/router'
router.push(path)
Why does it work like this:
In a Vue file, this is binded to the Vue object which is why you can use certain methods that are available there like $router or $store.
However in a normal JS file this is just binded to the global object that does not contain any of Vue's special functionality, which is why you have to import the router manually.

load routes via component from external api and add them to the router

I would like to load my routes from an external API. Some users might not have the permissions to access a module.
So my navbar makes an API call and gets all the modules returned. These module objects contain the path to the view file.
I tried to create a small sandbox to reproduce the problem
https://codesandbox.io/s/vue-routing-example-i5z1h
If you open this url in your browser
https://i5z1h.codesandbox.io/#/First
you will first get the following error
Url /First not found
but after clicking on the First module link in the navbar, the First view should get rendered.
I think the problem is related to the fact that the page has not yet started the navigation created event after loading and the module page is therefore not found. After changing a router URL the navigation component had enough time to add all the required routes to the router.
How can I load these URLs before the router leads to the first route and responds a 404 error?
The key idea here is to load the routes asynchronously which means you must defer loading of your SPA till that time. In your index.js or main.js, your code would be something like this:
// Some functions are assumed and not defined in the below code.
import Vue from 'vue';
import VueRouter from 'vue-router';
// Application root component
import App from './App.vue';
import { getRoutes } from './api';
// Register Vue plugins
Vue.use(VueRouter);
// Make API call here
// Some animation before the app is fully rendered.
showLoader();
getRoutes(/* Optional User data */)
.then((routesData) => {
// Stop the animation
stopLoader();
return routesData;
})
.then((routesData) => {
// processRoutes returns an array of `RouteConfig`
const routes = processRoutes(routesData);
const router = new Router({
routes: [
...routes,
{
path: '*',
component: NotFound
}
]
});
})
.then((router) => {
const app = new Vue({
el: '#app',
router,
template: '<App/>',
components: { App }
});
});
Additionally, there are a few things you need to do:
Routing is generally the higher-level concern. So if you consider DIP - Dependency Inversion and the stateful + singleton nature of the router, then it makes sense to bootstrap it at the very beginning. Thus, anything that router needs should be available. This means that the navbar component should not be responsible for making the API call. You must take it out.
Another possible solution is to use $router.addRoutes() method. But it is inadequate for your needs. It will not work considering authorization in mind. It will not prevent navigation.
On a philosophical level, when you are using SPA with client-side routing, then client-side routing is its own source of truth. It is reasonable to know all the routes upfront and hence most routers are designed with this idea in mind. Thus, a requirement like this is a poor fit for this paradigm. If you need something like this, then a server should possess the knowledge of client-side routes and during page refresh, the server should decide what to do - Load the SPA or reject with 404/403 page. And if the access is allowed, the server should inject routing data in the HTML page which will then be picked by Vue.js on the browser side. Many sophisticated SSR - Server-Side Rendering techniques exist to achieve this.
Alternative strategy: Use guards
Define all the routes upfront in your router for all the possible views of all the users.
Define guards for each authorized routes. All these guards would be resolved asynchronously.
Instead of loading routing data from API, use the API to return an Authorization Matrix. Use this API response in your route guards to determine the access.
To prevent calls to the same API multiple times, you can use some sort of caching like Proxy, Memoization, store etc. Generally, for a user, the Auth Matrix will not vary between the calls.
As an advantage of this, you can still load the application partially if required leading to meaningful user experience by reducing the user's time to interact with the application.

How to access a constant in main.js in another js file in vue.js framework?

I have a vue.js application and in the main.js file I have configured the Vuei18n as per the documentation. This is working perfectly and in order to access this in other components, I have added this to new Vue() instance and this is now accessible (with this.$i18n).
Now I have created a validator.js file for validation rules and I need to use the this.$i18n there, but its not working. I have also tried Vue.prototype.$i18n but that too not working. Can someone help me to find out where I went wrong ?
 exporting the i18n variable
I'll assume your app is a vue-cli app, or at least that you use webpack to build it
and therefore can use ES modules.
Working with vue-i18n you would do something like the following:
// step 1: define the i18n object via new Vue18n
const i18n = new VueI18n({
locale: DEFAULT_LANGUAGE,
messages,
});
// step 2: setup the Vue object to use this object:
new Vue({
i18n,
... store, router.... whatever
})
Where messages contain all the JSON's with the translations keys and values.
I guess you already are doing something like this.
And now, in your validator module you need the very same i18n object you plugged to Vue.
Instead of trying to get to Vue in your validator, you can just plain export the i18n varible from main.js:
export {i18n}
So, in your validator.js file, you can just import it:
import {i18n} from '#/main.js' // or whatever is the path
This is pretty much how I'm solving the validator internationalization problem in my own application.
Important note: circular dependencies
If you're already importing the validator.js in your main.js, you won't be able to import i18n from main in your validator module. To avoid such a problem, you would move the i18n initialization and exportation to another module, such as i18n.js, so the validator and the main file can import it independently. 
 Without es6 modules
In case you're not using webpack or another bundler to bundle your code, you can still just export the i18n object to the window object:
window.i18n = i18n
and then use it from whatever file. You just need to be careful to store the i18n object in window before any file will try to access it.
I think what you're looking for is Custom Events. According to this documentation, you should be able to emit your variable with something like below
this.$emit('send-i18n', this.$i18n)
Still according to the documentation, try to use v-on:send-i18n to retreive your value.
Hope it works.