Vue Navigation

This guide covers how routing works in an app built with Ionic and Vue.

The IonRouterOutlet component uses the popular Vue Router library under the hood. With Ionic and Vue Router, you can create multi-page apps with rich page transitions.

Everything you know about routing using Vue Router carries over into Ionic Vue. Let's take a look at the basics of an Ionic Vue app and how routing works with it.

A Brief Note

While reading this guide, you may notice that most of these concepts are very similar to the concepts found in Vue Router without Ionic Framework. You observation would be correct! Ionic Vue leverages the best parts of Vue Router to make the transition to building apps with Ionic Framework as seamless as possible. As a result, we recommend relying on Vue Router features as much as possible rather than trying to build your own routing solutions.

A Simple Route

Here is a sample routing configuration that defines a single route to the "/home" URL. When you visit "/home", the route renders the HomePage component.

router/index.ts

import { createRouter, createWebHistory } from '@ionic/vue-router';
import { RouteRecordRaw } from 'vue-router';
import HomePage from '@/views/Home.vue';

const routes: Array<RouteRecordRaw> = [
  {
    path: '/',
    name: 'Home',
    component: HomePage
  },
]

const router = createRouter({
  history: createWebHistory(process.env.BASE_URL),
  routes
});

export default router;

On the app's initial load, the app will render the HomePage component as that is what is configured here.

Handling Redirects

What if we wanted to land a different path on our initial load? For this, we can use router redirects. Redirects work the same way that a typical route object does, but just includes some different keys:

const routes: Array<RouteRecordRaw> = [
  {
    path: '/',
    redirect: '/home'
  },
  {
    path: '/home',
    name: 'Home',
    component: HomePage
  },
]

In our redirect, we look for the index path of our app. Then if we load that, we redirect to the home route.

Navigating to Different Routes

This is all great, but how does one actually navigate to a route? For this, we can use the router-link property. Let's create a new routing setup:

const routes: Array<RouteRecordRaw> = [
  {
    path: '/',
    redirect: '/home'
  },
  {
    path: '/home',
    name: 'Home',
    component: HomePage
  },
  {
    path: '/detail',
    name: 'Detail',
    component: DetailPage
  }
]

Say we start on the home route, and we want to add a button that takes us to the detail route. We can do this using the following HTML to navigate to the detail route:

<ion-button router-link="/detail">Go to detail</ion-button>

We can also programatically navigate in our app by using the router API:

<template>
  <ion-page>
    <ion-content>
      <ion-button @click="() => router.push('/detail')">Go to detail</ion-button>
    </ion-content>
  </ion-page>
</template>

<script lang="ts">
  import { IonButton, IonContent, IonPage } from '@ionic/vue';
  import { defineComponent } from 'vue';
  import { useRouter } from 'vue-router';

  export default defineComponent({
    name: 'HomePage',
    components: {
      IonButton, 
      IonContent, 
      IonPage
    },
    setup() {
      const router = useRouter();
      return { router };
    }
  })
</script>

Both options provide the same navigation mechanism, just fitting different use cases.

Lazy Loading Routes

The current way our routes are setup makes it so they are included in the same initial chunk when loading the app, which is not always ideal. Instead, we can set up our routes so that components are loaded as they are needed:

const routes: Array<RouteRecordRaw> = [
  {
    path: '/',
    redirect: '/home'
  },
  {
    path: '/home',
    name: 'Home',
    component: HomePage
  },
  {
    path: '/detail',
    name: 'Detail',
    component: () => import('@/views/DetailPage.vue')
  }
]

Here, we have the same setup as before only this time DetailPage has been replaced with an import call. This will result in the DetailPage component no longer being part of the chunk that is requested on application load.

Shared URLs versus Nested Routes

A common point of confusion when setting up routing is deciding between shared URLs or nested routes. This part of the guide will explain both and help you decide which one to use.

Shared URLs

Shared URLs is a route configuration where routes have pieces of the URL in common. The following is an example of a shared URL configuration:

const routes: Array<RouteRecordRaw> = [
  {
    path: '/dashboard', 
    component: DashboardMainPage,
  },
  {
    path: '/dashboard/stats',
    component: DashboardStatsPage
  }
];

The above routes are considered "shared" because they reuse the dashboard piece of the URL.

Nested Routes

Nested Routes is a route configuration where routes are listed as children of other routes. The following is an example of a nested route configuration:

const routes: Array<RouteRecordRaw> = [
  {
    path: '/dashboard/:id', 
    component: DashboardRouterOutlet,
    children: [
      {
        path: '',
        component: DashboardMainPage
      },
      { 
        path: 'stats', 
        component: DashboardStatsPage
      },
    ]
  }
];

The above routes are nested because they are in the children array of the parent route. Notice that the parent route renders the DashboardRouterOutlet component. When you nest routes, you need to render another instance of ion-router-outlet.

Which one should I choose?

Shared URLs are great when you want to transition from page A to page B while preserving the relationship between the two pages in the URL. In our previous example, a button on the /dashboard page could transition to the /dashboard/stats page. The relationship between the two pages is preserved because of a) the page transition and b) the url.

Nested routes are mostly useful when you need to render content in outlet A while also rendering sub-content inside of a nested outlet B. The most common use case you will run into is tabs. When you load up a tabs Ionic starter application, you will see ion-tab-bar and ion-tabs components rendered in the first ion-router-outlet. The ion-tabs component renders another ion-router-outlet which is responsible for rendering the contents of each tab.

There are very few use cases in which nested routes make sense in mobile applications. When in doubt, use the shared URL route configuration. We strongly caution against using nested routing in contexts other than tabs as it can quickly make navigating your app confusing.

Working with Tabs

When working with tabs, Ionic Vue needs a way to know which view belongs to which tab. The IonTabs component comes in handy here, but let's look at what the routing setup for this looks like:

const routes: Array<RouteRecordRaw> = [
  {
    path: '/',
    redirect: '/tabs/tab1'
  },
  {
    path: '/tabs/',
    component: Tabs,
    children: [
      {
        path: '',
        redirect: 'tab1'
      },
      {
        path: 'tab1',
        component: () => import('@/views/Tab1.vue')
      },
      {
        path: 'tab2',
        component: () => import('@/views/Tab2.vue')
      },
      {
        path: 'tab3',
        component: () => import('@/views/Tab3.vue')
      }
    ]
  }
]

Here, our tabs path loads a Tabs component. We provide each tab as a route object inside of the children array. In this example, we call the path tabs, but this can be customized.

Let's start by taking a look at our Tabs component:

<template>
  <ion-page>
    <ion-content>
      <ion-tabs>
        <ion-tab-bar slot="bottom">
          <ion-tab-button tab="tab1" href="/tabs/tab1">
            <ion-icon :icon="triangle" />
            <ion-label>Tab 1</ion-label>
          </ion-tab-button>

          <ion-tab-button tab="tab2" href="/tabs/tab2">
            <ion-icon :icon="ellipse" />
            <ion-label>Tab 2</ion-label>
          </ion-tab-button>

          <ion-tab-button tab="tab3" href="/tabs/tab3">
            <ion-icon :icon="square" />
            <ion-label>Tab 3</ion-label>
          </ion-tab-button>
        </ion-tab-bar>
      </ion-tabs>
    </ion-content>
  </ion-page>
</template>

<script lang="ts">
import { IonTabBar, IonTabButton, IonTabs, IonContent, IonLabel, IonIcon, IonPage } from '@ionic/vue';
import { ellipse, square, triangle } from 'ionicons/icons';

export default {
  name: 'Tabs',
  components: { IonContent, IonLabel, IonTabs, IonTabBar, IonTabButton, IonIcon, IonPage },
  setup() {
    return {
      ellipse, 
      square, 
      triangle,
    }
  }
}
</script>

If you have worked with Ionic Framework before, this should feel familiar. We create an ion-tabs component, and provide an ion-tab-bar. The ion-tab-bar provides and ion-tab-button components, each with a tab property that is associated with its corresponding tab in the router config.

IonRouterOutlet

The IonRouterOutlet component provides a container to render your views in. It is similar to the RouterView component found in other Vue applications except that IonRouterOutlet can render multiple pages in the DOM in the same outlet. When a component is rendered in IonRouterOutlet we consider this to be an Ionic Framework "page". The router outlet container controls the transition animation between the pages as well as controls when a page is created and destroyed. This helps maintain the state between the views when switching back and forth between them.

Nothing should be provided inside of IonRouterOutlet when setting it up in your template. While IonRouterOutlet can be nested in child components, we caution against it as it typically makes navigation in apps confusing. See Shared URLs versus Nested Routes for more information.

URL Parameters

Let's expand upon our original routing example to show how we can use URL parameters:

const routes: Array<RouteRecordRaw> = [
  {
    path: '/',
    redirect: '/home'
  },
  {
    path: '/home',
    name: 'Home',
    component: HomePage
  },
  {
    path: '/detail/:id',
    name: 'Detail',
    component: DetailPage
  }
]

Notice that we have now added :id to the end of our detail path string. URL parameters are dynamic portions of our route paths. When the user navigates to a URL such as /details/1 the "1" is saved to a parameter named "id" which can be accessed in the component when the route renders.

Let's look at how to use it in our component:

<template>
  <ion-page>
    <ion-header>
      <ion-toolbar>
        <ion-title>Details</ion-title>
      </ion-toolbar>
    </ion-header>

    <ion-content>
      Detail ID: {{ id }}
    </ion-content>
  </ion-page>
</template>

<script lang="ts">
import { IonContent, IonHeader, IonPage, IonTitle, IonToolbar } from '@ionic/vue';
import { defineComponent } from 'vue';
import { useRoute } from 'vue-router';

export default defineComponent({
  name: 'Detail',
  components: {
    IonContent, 
    IonHeader, 
    IonPage, 
    IonTitle, 
    IonToolbar
  },
  setup() {
    const route = useRoute();
    const { id } = route.params;
    return { id };
  }
})
</script>

Our route variable contains an instance of the current route. It also contains any parameters we have passed in. We can obtain the id parameter from here and display it on the screen.

More Information

For more info on routing in Vue using Vue Router, check out their docs at http://router.vuejs.org/.