Vue.js 2.0 transition on dynamic route not firing

Question

I found that transition is not firing on dynamic route with parameters. For exemple with the code below, when I am in /chapter/1 and I go to /chapter/2 there is no transition. But when I am in /chapter/1 and I go to /profile/1 there is one !

main.js file

require('normalize.css')

import Vue from 'vue'
import VueRouter from 'vue-router'
import App from './App'
import Panel from './components/Panel'
import Profile from './components/Profile'

window.bus = new Vue()

Vue.use(VueRouter)

const router = new VueRouter({
  routes: [
     { path: '/', redirect: '/chapter/1' },
     { name:'chapter', path: '/chapter/:id', component: Panel},
     { name:'profile', path: '/profile/:id', component: Profile}
  ]
})

new Vue({
  router,
  el: '#app',
  render: h => h(App)
})

App.vue template

<template>
  <div id="app">

    <transition name="fade" mode="out-in">
      <router-view></router-view>
    </transition>

    <div class="controls">
      <router-link :to="{ name: 'chapter', params: { id: Math.max(1, parseInt($route.params.id) - 1) }}">
        Prev
      </router-link>
      <router-link :to="{ name: 'chapter', params: { id: parseInt($route.params.id) + 1 }}">
        Next
      </router-link>
    </div>
  </div>
</template>

Maybe is due to the fact that vue-router doesn't destroy the parent component ? I didn't found a way to run the transition from the code. I tried this configuration on vue-router example pack and the behavior is the same.

---

quote from the doc

One thing to note when using routes with params is that when the user navigates from /user/foo to /user/bar, the same component instance will be reused. Since both routes render the same component, this is more efficient than destroying the old instance and then creating a new one. However, this also means that the lifecycle hooks of the component will not be called.

To react to params changes in the same component, you can simply watch the $route object

---

Should I post an issue ?

Thanks for your help !

Answer 1

Can you check this working example: https://jsfiddle.net/mani04/dLnz4rbL/

I attempted to use the method described under Transitioning Between Elements in the docs.

In my fiddle example, which mostly uses the code from your question description, I used a transition wrapper within component, as shown below:

<transition name="fade" mode="out-in">
    <div class="page-contents" :key="$route.params.id">
        This is my chapter component. Page: {{parseInt($route.params.id)}}
    </div>
</transition>

The document specifies that we need to provide a key to make them distinct elements for Vue.js. So I added your chapter ID as key.

I don't know if this is a hack or a proper solution, I moved from Angular2 to Vue only 2 weeks ago. But till someone gives you a better solution, you may use this method to get your transitions for dynamic routes.

Regarding posting this as an issue in github page of vue-router, I am not sure if this qualifies to be addressed / fixed, but you may definitely bring it to their notice. Fix may involve not reusing components, which is also not ideal. So it is a tough call for them. But the discussion should definitely be interesting! Please post back the issue link here if you decide to create one :-)