Introduction
In a JavaScript web application, a router is responsible for synchronizing the view displayed with the content in the browser’s address bar. It manages URL changes when a user interacts with the page and ensures the correct view is shown for a specific URL.
Traditionally, the web is built around URLs, where hitting a specific URL displays a corresponding page. However, with the advent of applications running within the browser, many applications broke this URL-page interaction, requiring manual URL updates using the browser’s History API.
To solve this problem, a router is needed to sync URLs to views in your app. The Vue Router library is the recommended solution for Vue.js applications. Although Vue does not enforce its use, Vue Router is maintained by the same people who maintain Vue, ensuring a consistent integration within the framework.
Installation
Vue Router can be installed through npm using the package named vue-router. If you’re using Vue via a script tag, you can include Vue Router using the following link:
<script src="https://unpkg.com/vue-router"></script>
Vue CLI users can install Vue Router using the npm command:
npm install vue-router
After installation, import Vue Router in your app by calling Vue.use(VueRouter) after importing vue:
import Vue from 'vue'
import VueRouter from 'vue-router'
Vue.use(VueRouter)
The Router Object
Once Vue Router is installed, the router object can be accessed using this.$router in any component of the app. The router object offers several useful features for navigating to new routes, such as push(), replace(), and go() methods, which resemble the History API’s pushState, replaceState, and go methods.
Defining the Routes
To define routes in your Vue app, you can use the Vue Single File Component. The template should include a <router-link> component for navigation and a <router-view> component to display the content matching the current URL.
A <router-link> component renders an a tag by default. When the route changes, a router-link-active class is added to the active link element, allowing for easy styling.
In the JavaScript part, import the necessary components and define the route components. Pass the routes to the router object and provide it to the Vue root instance.
Using Named Routes to Pass Parameters
To pass parameters to the router’s push and replace methods, you can use named routes. With named routes, you can pass parameters to the new route by specifying the route’s name and the corresponding params. This can be done using this.$router.push({ name: 'routeName', params: { paramName: value } }) and this.$router.replace({ name: 'routeName', params: { paramName: value } }).
What Happens When a User Clicks a Router Link
When a user clicks a <router-link>, the application renders the route component that matches the URL provided in the link. The new route component’s guards are called, and the old route component is destroyed.
Route Guards
Route guards, similar to life cycle hooks or middleware, are functions called at specific times during the execution of the application. Vue Router provides global guards through the beforeEach(), beforeResolve(), and afterEach() methods. Additionally, route components offer individual guards such as beforeRouteEnter(), beforeRouteUpdate(), and beforeRouteLeave().
Dynamic Routing
Dynamic routes allow for handling URLs with varying segments. You can use dynamic segments by specifying a placeholder in the route path, such as /post/:post_slug. Within the component, you can access the parameters using $route.params.*.
Using Props
Instead of tightly coupling a component with the router using $route.params.*, you can pass route data as props by setting the props option to true in the route object.
Nested Routes
Nested routes allow for handling multiple dynamic segments within the same URL. By using the <router-view> component, you can nest routes and display components based on the URL structure.
Conclusion
The Vue Router is a powerful tool for managing routing in Vue.js applications. By following the steps outlined in this guide, you can seamlessly integrate routing into your Vue app and enable dynamic navigation between different views.
Tags: Vue Router, Routing, JavaScript, Vue.js