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Vue Router 4 is in beta and it’s subject to change.
To build a single page app easily, we got to add routing so that URLs will be mapped to components that are rendered.
In this article, we’ll look at how to use Vue Router 4 with Vue 3.
Async Scrolling Behavior
We can change the scrolling behavior to be async.
To do that, we can write:
<!DOCTYPE html>
<html lang="en">
<head>
<script src="https://unpkg.com/vue@next"></script>
<script src="https://unpkg.com/vue-router@4.0.0-beta.7/dist/vue-router.global.js"></script>
<title>App</title>
</head>
<body>
<div id="app">
<p>
<router-link to="/foo">foo</router-link>
<router-link to="/bar">bar</router-link>
</p>
<router-view></router-view>
</div>
<script>
const Foo = {
template: `<div>
<p v-for='n in 100'>{{n}}</p>
</div>`
};
const Bar = {
template: `<div>
<p v-for='n in 100'>{{n}}</p>
</div>`
};
const routes = [
{
path: "/foo",
component: Foo
},
{
path: "/bar",
component: Bar
}
];
const router = VueRouter.createRouter({
history: VueRouter.createWebHistory(),
routes,
scrollBehavior(to, from, savedPosition) {
return new Promise((resolve, reject) => {
setTimeout(() => {
resolve({ left: 0, top: 500 });
}, 500);
});
}
});
const app = Vue.createApp({});
app.use(router);
app.mount("#app");
</script>
</body>
</html>
We have the scrollBehavior method that returns a promise that resolves to an object with the scroll position.
The left and top properties are the new properties for the x and y coordinates.
They replace the x and y properties in Vue Router 3.
Lazy Loading Routes
We can lazy load routes in our app.
For example, we can write:
<!DOCTYPE html>
<html lang="en">
<head>
<script src="[https://unpkg.com/vue@next](https://unpkg.com/vue@next)"></script>
<script src="[https://unpkg.com/vue-router@4.0.0-beta.7/dist/vue-router.global.js](https://unpkg.com/vue-router@4.0.0-beta.7/dist/vue-router.global.js)"></script>
<title>App</title>
</head>
<body>
<div id="app">
<p>
<router-link to="/foo">foo</router-link>
<router-link to="/bar">bar</router-link>
</p>
<router-view></router-view>
</div>
<script>
const Foo = () =>
Promise.resolve({
template: `<div>foo</div>`
});
const Bar = () =>
Promise.resolve({
template: `<div>bar</div>`
});
const routes = [
{
path: "/foo",
component: Foo
},
{
path: "/bar",
component: Bar
}
];
const router = VueRouter.createRouter({
history: VueRouter.createWebHistory(),
routes
});
const app = Vue.createApp({});
app.use(router);
app.mount("#app");
</script>
</body>
</html>
We have the Foo and Bar components.
They are defined by creating a promise that resolves to the component definition.
With Webpack, we can also use the import function to import our component.
For example, we can write:
import('./Foo.vue')
import returns a promise that resolves to the component, and it works the same way as the promise definition above.
Grouping Components in the Same Chunk
We can group components in the same chunk bu creating components with functions:
const Foo = () => import(/* webpackChunkName: "group-foo" */ './Foo.vue')
const Bar = () => import(/* webpackChunkName: "group-foo" */ './Bar.vue')
const Baz = () => import(/* webpackChunkName: "group-foo" */ './Baz.vue')
We have comments with webpackChunkName with the chunk name.
Navigation Failures
We can handle navigation errors with programmatic navigation.
For example, we can write:
<!DOCTYPE html>
<html lang="en">
<head>
<script src="https://unpkg.com/vue@next"></script>
<script src="https://unpkg.com/vue-router@4.0.0-beta.7/dist/vue-router.global.js"></script>
<title>App</title>
</head>
<body>
<div id="app">
<p>
<router-link to="/foo">foo</router-link>
<a href="#" [@click](http://twitter.com/click "Twitter profile for @click").stop="go">bar</a>
</p>
<router-view></router-view>
</div>
<script>
const Foo = {
template: `<div>foo</div>`
};
const Bar = {
template: `<div>bar</div>`,
beforeRouteEnter(to, from, next) {
next(new Error());
}
};
const routes = [
{
path: "/foo",
component: Foo
},
{
path: "/bar",
component: Bar
}
];
const router = VueRouter.createRouter({
history: VueRouter.createWebHistory(),
routes
});
const app = Vue.createApp({
methods: {
go() {
this.$router.push("/bar").catch((failure) => {
console.log(failure);
});
}
}
});
app.use(router);
app.mount("#app");
</script>
</body>
</html>
to handle navigation errors.
We a beforeRouterEnter method in the Bar component.
It calls next with an Error instance within the method.
This will cause the Error instance to be shown in the console.
In the root Vue instance, we have the go method that tries to go to the /bar route with the push method.
The catch method’s callback has the failure parameter that has the Error instance that’s thrown.
Conclusion
We can change scrolling behavior to be async.
Also, components can be grouped into chunks and lazy-loaded.
Finally, we can handle errors that are raised from programmatic navigation.
