Vue Router: does this.$router.push navigate to a new URL? - vue.js

I read the documentation of vue-router (https://router.vuejs.org/guide/essentials/navigation.html)
This is the method called internally when you click a ,
so clicking is the equivalent of calling
router.push(...)
As far as I know clicking router-link element navigates to the URL placed in "to" attribute. However, according to History API
(https://developer.mozilla.org/en-US/docs/Web/API/History_API#Examples), history.pushState(...) only changes the history and does not navigate to a new URL.
So... how can we explain this contradiction?

I think you need to define exactly what you mean by "navigate to a new URL"; to me it can mean either reloading the page at a new URL, or simply changing the URL in the address bar without reloading the page.
history.pushState() does change the URL, but it doesn't cause the browser to perform a full page reload as is typical when you click a link. This is how "single page apps" work – they intercept <a> clicks and use history.pushState() to prevent the page from reloading.
history.pushState(...) only changes the history and does not navigate to a new URL.
Here I think "and does not navigate to a new URL" is wrong – it does, except the page doesn't reload.

There is no contradiction here. There is no reason why the Vue Router could not do a change to the url with the history api and change the component as rendered in various router-view components.
When you include a router-link in your code, this is a component like any other. Vue will render this component. The interesting part is this:
const router = this.$router
// And later
const handler = e => {
if (guardEvent(e)) {
if (this.replace) {
router.replace(location)
} else {
router.push(location)
}
}
}
const on = { click: guardEvent }
if (Array.isArray(this.event)) {
this.event.forEach(e => { on[e] = handler })
} else {
on[this.event] = handler
}
For the history api, you can see in the source that for a this.$router.push(..) we transition, and we push the state with this pushState function. The transition itself can be found in history/base.js.

Related

Is there anyway to ignore the *failure: Avoided redundant navigation to current location* error using Vue Router and just refresh the page?

I see this question has been asked a few times on here, but none of the answers have really helped me in this current situation.
I have an app I'm working on with a sidebar with tabs that link to different dashboards. Each of the SidebarLinks are a router-link with the to key being fed the route prop from the main component.
Inside one of these dashboards, the Analysis dashboard, there is another router that routes you to child routes for specific Analyses with their own ids (EX: /analysis/1).
The user clicks on a button for a specific analysis and they are routed to a page containing that information, on the same page.
The Error
When I click the Analysis SidebarLink the route in the url changes back to /analysis, but the page doesn't update/refresh.
I don't get an error in the console, but I do get the failure in the devtools.
I understand that Vue Router doesn't route back to a route you are already on, but I need it to. If you refresh the page when the url is just /analysis it routes back to it's inital state.
Is there anyway to refresh when it rereoutes to /analysis? Or a way to handle this error to work as intended?
What I've tried
I've tried changing the router-link to an <a> tag and programatically use router.push and then catch the error, but that doesn't do anything.
I've tried checking if the route.fullPath.contains("/analysis") and then just do router.back() but that doesn't seem to work either.
SidebarLink router function
function goToRoute() {
console.log(`route.fullPath → `, route.fullPath)
if (route.fullPath.match('/analysis*') as any) {
console.log('route includes /analysis')
router.back()
} else {
console.log('route doesnt inclue /analysis')
router
.push({
path: props.route,
})
.catch(() => {})
}
}
Inital /analysis Page
This is what the page looks like normally
/analysis/1 Page
This is what the route to analysis/1 looks like (url changes)
/analysis/1 Page When Issue Analysis SidebarLink Clicked
This is what the route to analysis looks like when the sidebarlink is clicked (url changes, but the page stays the same)
I suspect you are fetching your data from a backend service or data files
If yes you can refetch the data everytime the route param changed by watching it.
watch: {
'$route.params.id': function (id) {
if(id)
this.$store.dispatch('fetchOneAnalys', id)
else
this.$store.dispatch('fetchAllAnalyses')
}

Why does the browser display cached Vue.js view on route/url change?

I have a homepage with <router-link> tags to views. It is a simple master/detail relationship where the Homepage is a catalogue of products and the Product detail page/view shows information on each item.
When I first launch the website and click on an item on the Homepage view (e.g. URL: http://localhost:8080/100-sql-server-2019-licence), the Product view gets loaded and the product detail loads fine.
If I then press the back button in the browser to return to the Homepage and then click on a different Product (e.g. URL: http://localhost:8080/101-oracle-12c-licence), the URL in the browser address bar changes but I get the previous product's information. Its lightning quick and no new network calls are done which means its just showing a cached page of the previous product. If I then hit the refresh button while on that page, the network call is made and the correct product information is displayed.
I did a search online but couldn't find this problem described on the search results. Could anyone point me in the right direction of how to cause a refresh/re-render of a route when the route changes?
What is happening
vue-router will cache your components by default.
So when you navigate to the second product (that probably renders the same component as the first product), the component will not be instantiated again for performance reasons.
From the vue-router documentation:
For example, for a route with dynamic params /foo/:id, when we
navigate between /foo/1 and /foo/2, the same Foo component instance
will be reused.
The easy (but dirty) fix
The easy -but hacky and not recommended - way to solve this is to give your <router-view /> a key property, e.g.:
<router-view :key="$route.fullPath" />
This will force vue-router to re-instantiate the view component every time the url changes.
However you will loose all performance benefits you would normally get from the caching.
Clean fix: properly handling route changes
The clean way to solve this problem is to react to the route-change in your component (mostly this boils down to moving ajax calls from mounted into a $route watcher), e.g.:
<script>
export default {
data() {
return {
productDetails: null,
loading: false
};
},
watch: {
'$route': {
// with immediate handler gets called on first mount aswell
immediate: true,
// handler will be called every time the route changes.
// reset your local component state and fetch the new data you need here.
async handler(route) {
this.loading = true;
this.productDetails = null;
try {
// example for fetching your product data
const res = await fetch("http://give.me.product.data/" + encodeURIComponent(route.params.id));
this.productDetails = await res.json();
} finally {
this.loading = false;
}
}
}
}
};
</script>
Alternative: Navigation Guards
Alternatively you could also use vue-routers In-Component Navigation Guards to react to route changes:
<script>
export default {
async beforeRouteUpdate (to, from, next) {
// TODO: The route has changed.
// The old route is in `from`, the new route in `to`.
this.productData = await getProductDataFromSomewhere();
// route will not change before you haven't called `next()`
next();
}
};
</script>
The downside of the navigation guards is that you can only use them directly in the component that the route renders.
So you can't use navigation guards in components deeper within the hierarchy.
The upside is that the browser will not view your site before you call next(), which gives you time to load the data necessary before your route is displayed.
Some helpful ressources
Vue Router Navigation Guards Documentation
vue-router github issue
Similar Question about vue-router component reuse on stackoverflow

how do I bring up "Are you sure you want to leave page?" popup in vue.js router?

I'm building a vue.js application. We'd like to have a popup come up when the user attempts to leave a specific page. The popup should say "Are you sure you want to leave the page?" I know I can implement something in the beforeRouteLeave hook of the component, but I'm wondering if there's a way to implement this in the beforeEach event of the router (i.e. not the component). The reason I'd like to use the router is because beforeEach in the router seems to respond to the user entering a different path in the browser url bar, whereas the beforeRouteLeave hook on the component does not. However, I don't have access to the popup in the router whereas I do in the component (the popup would just be part of the template).
So the question is: how can I bring up a popup in the router before the user actually leaves the page?
Thanks.
First you can assign a name for each of your routes objects in routes array inside your router or another field like requiredConfirmation or something like that, imagine that we have a routes like this :
routes : [
{
path : '/needconfirm',
component : NeedConfirmToLeaveCom,
name : 'needconfirm-route1'
},
{
path : '/neednotconfirm',
component : NeedNotConfirmToLeaveCom,
name : 'normal-route1'
},
]
then you can use router.beforeEach to set some conditions or some confirmations based on your Origin route and Destination route.
something like this :
router.beforeEach((to,from,next) => {
if(from.name.startsWith("needconfirm-")) {
if(window.confirm("Are you sure you want to leave the page?")) {
next();
}
}else next();
});
UPDATE * :
if you want to use some custom components for your popup, you can use vuex to store your component's logic and toggler and import that component in your App.Vue or other root/child components you wish. because you have access to your store management using $store right?
UPDATE ** :
and one other thing i want to mention, if you want to save some progress or state and because of that you want to get confirmation from user (progress will lost if they switch route), you should consider using Vuex to store your progress or state of your application and if you want more persisted solution you can use VuexPersisted store management which uses LocalStorage.
Vue router navigation guards document
Vuex Doc
You should use beforeunload event listener on the main component in that view.
MDN Reference
Depending on the browser, it will show the popup with default values populated.
This is how I use it in the created hook of the main component
window.addEventListener("beforeunload", (e) => {
e.preventDefault()
// chrome requires returnValue to be set
const message = "You have unsaved changes. Are you sure you wish to leave?"
e.returnValue = message
return message
})

Is it possible for Nuxt middleware to wait for asyncData requests to resolve?

I have a some middleware in my Nuxt app that closes a fullscreen mobile menu when a new route is clicked. What I am experiencing is the following:
user clicks nuxt-link
menu closes
asyncData delay (still shows current page)
new page is loaded upon resolved asyncData
What I would like is the following:
user clicks nuxt-link
asyncData delay (if exists)
menu closes upon new page load
Is it possible to have an asyncData watcher in Nuxt middleware?
I know I can hack this by creating a store value that tracks asyncData load, but I'd rather not have to wire up such a messy solution to each and every page that uses asyncData.
Note - not every page uses asyncData.
I think that the best option would be to leave the menu open, and then when the new page finishes loading (probably on the mounted hook) send an event or action to close the menu.
I figured this out in a more elegant solution than having to implement a store.dispatch function on each individual asyncData function.
So what I did was use a custom loading component: https://nuxtjs.org/api/configuration-loading/#using-a-custom-loading-component
However, instead of showing a progress bar or any sort of loading animation, I just used this component to set a loading state in my vuex store. Note - it forces you to have a template, but I just permanently disabled it.
<template>
<div v-if="false"></div>
</template>
<script>
export default {
methods: {
start() {
this.$store.dispatch('updateLoadingStatus', true);
},
finish() {
this.$store.dispatch('updateLoadingStatus', false);
}
}
};
</script>
Then in my middleware, I set up an interval watcher to check when loading has stopped. When stopped, I stop the interval and close the mobile menu.
export default function({ store }) {
if (store.state.page.mobileNav) {
if (store.state.page.loading) {
var watcher = setInterval(() => {
if (!store.state.page.loading) {
store.dispatch('updateMobileNav', false);
clearInterval(watcher);
}
}, 100);
} else {
store.dispatch('updateMobileNav', false);
}
}
}
This doesn't specifically have to be for a mobile menu open/close. It can be used for anything in middleware that needs to wait for asyncData to resolve. Hope this can help anyone in the future!

Vue router reloading the current route

Without reloading the whole page I need to reload the current route again (Only a component reload) in a vue app.
I am having a path in vue router like below,
{
path: "/dashboard",
name: "dashboard",
component: loadView("Dashboard"),
},
When user clicks on the Dashboard navigation item user will be redirected to the Dashboard page with vue router programmatic navigation
this.$router.push({ name: "dashboard" });
But when user already in the dashboard route and user clicks the Dashboard nav item again nothing happens. I think this is vue router's default behaviour. But I need to force reload the Dashboard component (Not to refresh the whole page).
I can't use beforeRouteUpdate since the router is not updated. Also I have tried the global before guards like beforeEach. But it is also not working.
How can I force reload the dashboard component without reloading the whole page?
It can be done in two ways.
1) Try doing vm.$forceUpdate(); as suggested here.
2) You can take the strategy of assigning keys to children, but whenever you want to re-render a component, you just update the key.
<template>
<component-to-re-render :key="componentKey" />
</template>
<script>
export default {
data() {
return {
componentKey: 0,
};
},
methods: {
forceRerender() {
this.componentKey += 1;
}
}
}
</script>
Every time that forceRerender is called, the prop componentKey will change. When this happens, Vue will know that it has to destroy the component and create a new one.
What you get is a child component that will re-initialize itself and “reset” its state.
Not mentioned here, but as the offered solutions require a lot of additional work just to get the app to render correctly, which imo is a brittle solution.. we have just implemented another solution which works quite well..
Although it is a total hack.
if (this.$route.name === redirect.name) {
// this is a filthy hack - the vue router will not reload the current page and then have vue update the view.
// This hack routes to a generic page, then after this has happened the real redirect can happen
// It happens on most devices too fast to be noticed by the human eye, and in addition does not do a window
// redirect which breaks the mobile apps.
await this.$router.push({
name: RouteNames.ROUTE_REDIRECT_PLACEHOLDER
});
}
... now continue to do your normal redirect.
Essentially, redirect to a placeholder, await the response but then immediately continue to another page you actually wanted to move toward