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Svelte Navigator

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Simple, accessible routing for Svelte.

Svelte Navigator is an accessible and relatively lightweight Single Page App Router inspired by react-router and @reach/router.

This started as a fork of svelte-routing, with added configuration options and access to parts of the Routers context through React-esque hooks.

Features

  • Accessible routing: The Router manages focus in your app automatically and makes announcements to screen reader users
  • Relative routing: Paths and links are relative to the parent Route and Router
  • Nestable Routes for easy, flexible and reusable component composition
  • Automatic route ranking: The Router chooses the best match automatically, so you don't need to worry about the order of your Routes
  • Route parameters user/:id and (namable) wildcards blog/*, blog/*wildcardName
  • React-esque hooks api for accessing parts of the Router context
  • Nestable Routers for seamless merging of many smaller apps
  • HTML5 history mode by default (Memory mode as fallback, or for testing)
  • SSR (Server Side Rendering) support
  • TypeScript ready

Table of Contents

Getting started

Look at the example folder for a few example project setups, or checkout the examples in the Svelte REPL:

Installation

With yarn:

yarn add svelte-navigator

With npm:

npm install --save svelte-navigator

Usage

Basic Setup for a client-side SPA:

<!-- App.svelte -->
<script>
	import { Router, Link, Route } from "svelte-navigator";
	import Home from "./routes/Home.svelte";
	import About from "./routes/About.svelte";
	import Blog from "./routes/Blog.svelte";
	import Search from "./routes/Search.svelte";
</script>

<Router>
	<nav>
		<Link to="/">Home</Link>
		<Link to="about">About</Link>
		<Link to="blog">Blog</Link>
	</nav>
	<div>
		<Route path="/">
			<Home />
		</Route>
		<Route path="about" component={About} />
		<Route path="blog/*">
			<Route path="/">
				<Blog />
			</Route>
			<Route path=":id" component={BlogPost} />
		</Route>
		<Route path="search/:query" let:params>
			<Search query={params.query} />
		</Route>
	</div>
</Router>

Svelte Navigator uses the HTML5 History API by default. For it to work properly, you need to setup your server correctly. If you're using sirv, as is common with a lot of Svelte projects, you need to pass it the --single option.

You can read more about the History API here:

SSR Caveat

In the browser we wait until all child Route components have registered with their ancestor Router component before we let the Router pick the best match. This approach is not possible on the server, because when all Route components have registered and it is time to pick a match the SSR has already completed, and a document with no matching Route will be returned.

We therefore resort to picking the first matching Route that is registered on the server, so it is of utmost importance that you sort your Route components from the most specific to the least specific if you are using SSR.

FAQ

I'm using Vite. Why am I getting errors with svelte-navigator?

Vite tries to optimize the dependencies of your app. Unfortunately, this process can break svelte-navigator, because it creates two versions of a variable, svelte-navigator uses internally. To fix this update your vite.config.js (or vite.config.ts) file:

import { defineConfig } from "vite";
import svelte from "@sveltejs/vite-plugin-svelte";

// https://vitejs.dev/config/
export default defineConfig({
	// ... your config ...
	plugins: [svelte() /* ... your plugins ... */],
	// Add this line:
	optimizeDeps: { exclude: ["svelte-navigator"] },
});

I'm coming from svelte-routing. How can I switch to svelte-navigator?

svelte-navigator started as a fork of svelte-routing. Its API is largely identical. Svelte Navigator mainly adds functionality through hooks. Things that work in Svelte Routing should just work in Svelte Navigator as well. Switching libraries is as easy as updating your imports:

// Change your imports from
import { Router, Route /* , ... */ } from "svelte-routing";
// to
import { Router, Route /* , ... */ } from "svelte-navigator";

Enjoy added functionality, like access to the current location or params through hooks, scoped paths in navigate with useNavigate, nested Routes, improved accessibility and more.

Why am I getting a warning about unused props for my route components?

To be precise, this warning: <Svelte component> was created with unknown prop 'location' & 'navigate'.

This happens, because Svelte Navigator injects the current location and a scoped navigate function to components rendered via the Route's component prop. To avoid the warning, you can instead render your components as Route children:

<!-- No unknown props will be injected -->
<Route path="my/path">
	<MyComponent />
</Route>

<!-- `location` and `navigate` props will be injected -->
<Route path="my/path" component="{MyComponent}" />

Read more in the Route section of the API docs.

Why don't CSS classes work with Link?

<style>
	/*
		Svelte will mark this class as unused and will remove it from
		the CSS output.
	*/
	.my-link { /* ... */ }
</style>

<Link class="my-link" to="my-path">...</Link>

Having a class attribute on Svelte components does not work with Svelte's CSS scoping. Svelte does not treat class props to components as special props and does not recognize them as classnames either. Theoretically Link could use the class prop for something entirely different than styling, so Svelte can't make any assumptions about it. As far as Svelte is concerned the class="my-link" attribute and the .my-link are totally unrelated.

To work around this, you can often make use of the scoping of a wrapping or an inner html element:

<style>
	/*
		`.wrapper` is a standard html element, so Svelte will recognize its
		`class` attribute and scope any styles accordingly.
		Since part of the selector is scoped you don't need to worry about the
		global part leaking styles.
	*/
	.wrapper :global(.my-link) { /* ... */ }

	/*
		Again, scoping works just fine with `.link-content`, so it can be styled
		as expected. This way you don't have direct access to the `<a />` tag of
		the `Link` however.
	*/
	.link-content { /* ... */ }
</style>

<div class="wrapper">
	<Link class="my-link" to="my-path">...</Link>
</div>

<Link to="my-path">
	<span class="link-content">...</span>
</Link>

If that does not work for you, you can use the use:link action instead (which has its limitations though, see link section in the API docs).

<script>
	import { link } from "svelte-navigator";
</script>

<style>
	/* This works as expected */
	.my-link {
		/* ... */
	}
</style>

<a class="my-link" href="my-path" use:link>...</a>

What are the weird rectangles around the headings in my app?

Focus outline around heading

These outlines appear, because Svelte Navigator focuses a heading inside the Route that was rendered after a navigation. This helps people relying on assistive technology, such as screen reader users, orientate on your website. If the router didn't take focus, and you were to click a link, it would remain focused after the navigation. Screenreader users would just not know that something changed on the page. (This is a common problem with spa routers). The idea of focusing a heading is, that it gives the user a starting point from where they can tab to the changed content. Since it is just the starting point, you can disable the focus ring for just the headers, which aren't focusable by default anyway. Or you could style them to better suit your design (see this article about styling focus indicators). But please, don't disable focus rings alltogether!

Testing

When testing your app's components it is sometimes neccessary to have them rendered inside an instance of Router or Route. A component could for example use the useNavigate hook to redirect after some user interaction. This will however fail if the component is not somewhere inside a Router. Similarly useing the useFocus hook will only work when the component is somewhere inside a Route.

If you're testing your app with @testing-library/svelte a custom render function and a WrapRouter component can do the trick:

// renderWithRouter.js
import { render } from "@testing-library/svelte";
import WrapRouter from "./WrapRouter.svelte";

/**
 * Test-render a component, that relies on some of svelte-navigator's
 * features, inside a Router.
 *
 * @param component The component you want to wrap in a Router
 * @param componentProps The props you want to pass to it
 * @param routerOptions Futher configuration (`onNavigate`,
 * `withRoute`, `initialPathname`)
 * @param options Options for testing library's `render` function
 */
const renderWithRouter = (component, componentProps, routerOptions, options) =>
	render(WrapRouter, { component, componentProps, ...routerOptions }, options);

export default renderWithRouter;
<!-- WrapRouter.svelte -->
<script>
	import { onDestroy } from "svelte";
	import {
		Router,
		Route,
		createMemorySource,
		createHistory,
	} from "svelte-navigator";

	/** The component you want to wrap in a Router */
	export let component;
	/** The props you want to pass to it */
	export let componentProps;
	/**
	 * A callback you can use to check if a navigation has occurred.
	 * It will be called with the new location and the action that lead
	 * to the navigation.
	 */
	export let onNavigate = () => {};
	/**
	 * If true, the component will be wrapped in a Route component as well.
	 * Some features of svelte-navigator can only be used inside a Route,
	 * for example `useParams`.
	 */
	export let withRoute = false;
	/** Supply an initial location to the Router */
	export let initialPathname = "/";

	const history = createHistory(createMemorySource(initialPathname));

	const unlisten = history.listen(onNavigate);

	onDestroy(unlisten);
</script>

<Router {history}>
	{#if withRoute}
	<Route path="*">
		<svelte:component this="{component}" {...componentProps} />
	</Route>
	{:else}
	<svelte:component this="{component}" {...componentProps} />
	{/if}
</Router>

Then import it in your test script:

import MyComponent from "./MyComponent.svelte";
import renderWithRouter from "../test/renderWithRouter";

it("works", () => {
	const { getByTestId } = renderWithRouter(MyComponent);
	expect(getByTestId("my-input")).toHaveValue("my-value");
});

API

Components

The main elements to configure and use routing in your Svelte app.

Router

The Router component supplies the Link and Route descendant components with routing information through context, so you need at least one Router at the top of your application. It assigns a score to all its Route descendants and picks the best match to render.

<Router>
	<Link to="profile">Go to /profile</Link>
	<Link to="blog">Go to /blog</Link>
	<Route path="blog" component={Blog} />
	<Route path="profile" component={Profile} />
</Router>

The Router will automatically manage focus in your app. When you change Routes, it will focus the first heading in the matched Route.

If you have multiple Routers, for example one for a navigation bar and one for the main content, make sure to pass primary={false} to all Routers, you don't want to manage focus (in this case the nav Router).

<Router primary={false}>
	<nav>
		<Link to="profile">Go to /profile</Link>
		<Link to="blog">Go to /blog</Link>
	</nav>
</Router>
<!-- ... -->
<Router>
	<main>
		<Route path="blog" component={Blog} />
		<Route path="profile" component={Profile} />
	</main>
</Router>

If you want to focus a different element, like a skip-navigtion-link or an info text, you can use the useFocus hook, to specify a custom focus element.

Svelte navigator also announces navigations to a screen reader. You can customize its message (i.e. for localization) via the a11y.createAnnouncement prop.

If you're interested in accessibility concerns in SPA routers you can check out this article, which provided much of the information, regarding focus management, used for implementing Svelte Navigators focus management.

<!-- App.svelte -->
<script>
	import { Router, Route, Link } from "svelte-navigator";

	// Provide a custom message when navigating using
	// a routes `meta` information
	function createAnnouncement(route, location) {
		const viewName = route.meta.name;
		const { pathname } = location;
		return `Navigated to the ${viewName} view at ${pathname}`;
	}
</script>

<Router a11y="{{ createAnnouncement }}">
	<Link to="profile">Go to /profile</Link>
	<Route
		path="profile"
		component="{Profile}"
		meta="{{ name: 'user profile' }}"
	/>
	<Route path="blog/*" meta="{{ name: 'blog' }}">
		<Blog />
	</Route>
</Router>

<!-- Blog.svelte -->
<script>
	import { Route, Link, useFocus } from "svelte-navigator";

	// Provide a custom element to focus when this Route is navigated to
	const registerFocus = useFocus();

	function skipNavigation() { /* ... */ }
</script>

<button use:registerFocus on:click={skipNavigation}>
	Skip navigation
</button>
<Link to="svelte">Go to /blog/svelte</Link>
<Link to="navigator">Go to /blog/navigator</Link>
<Route path="svelte">Yeah, Svelte!</Route>
<Route path="navigator">Yeah, Routing!</Route>

Router components can also be nested to allow for seamless merging of many smaller apps. Just make sure not to forget the wildcard (*) in the parent Routes path.

It's probably easier to nest Routes though.

<!-- App.svelte -->
<Router>
	<Link to="profile">Go to /profile</Link>
	<Route path="profile" component="{Profile}" />
	<Route path="blog/*">
		<Blog />
	</Route>
</Router>

<!-- Blog.svelte -->
<Router>
	<Link to="svelte">Go to /blog/svelte</Link>
	<Link to="navigator">Go to /blog/navigator</Link>
	<!-- Break out of the scope of the current Router -->
	<Link to="../profile">Go to /profile</Link>
	<Route path="svelte">Yeah, Svelte!</Route>
	<Route path="navigator">Yeah, Routing!</Route>
	<Route path=":id" let:params>
		<BlogPost id={params.id} />
	</Route>
</Router>

When you are serving your app from a subdirectory on your server, you can add a basepath prop to the router. It will be prepended to all routes and to all resolved navigations (i.e. using Link, useNavigate or useResolve). A properly formatted basepath should have a leading, but no trailing slash.

<Router basepath="/base">
	<Link to="profile">Go to /base/profile</Link>
	<Link to="blog">Go to /base/blog</Link>
	<Route path="blog" component={Blog} />
	<Route path="profile" component={Profile} />
</Router>

By default Routers use the HTML5 history API for navigation. You can provide a different history through the history prop. Svelte Navigator ships with a memory based history, which is used, when the application does not seem to run in a browser (i.e. in a test environment) or in an embedded page, like the Svelte REPL. You can explicitly set the memory history or you can provide your own implementation (for example a Hash based history).

<script>
	import { createHistory, createMemorySource } from "svelte-navigator";

	const memoryHistory = createHistory(createMemorySource());
</script>

<Router history="{memoryHistory}">
	<!-- ... -->
</Router>
Properties
Property Type Default Value Description
basepath string '/' The basepath property will be added to all path properties of Route descendants and to every navigation, that has access to the Routers context (from a Link with a to property or via useNavigate). This property can be ignored in most cases, but if you host your application on e.g. https://example.com/my-site, the basepath should be set to /my-site. Note that navigate and the link and links actions don't have access to the context. You may resolve the link manually using the useResolve hook.
url string '' The url property is used in SSR to force the current URL of the application and will be used by all Link and Route descendants. A falsy value will be ignored by the Router, so it's enough to declare export let url = ''; for your topmost component and only give it a value in SSR.
history HistorySource <HTML5 History> The history property can be used to use a navigation method other than the browsers History API (See custom Hash based history).
primary boolean true If set to false, the Router will not manage focus for its children. Analougus to the Routes primary prop.
a11y object Configuration object for Svelte Navigators accessibility features
a11y.createAnnouncement CreateAnnouncement route => 'Navigated to ${route.uri}' Function to create an announcement message, that is read by screen readers on navigation. It takes the matched Route and the current location as arguments and returns a string or a Promise, that resolves to a string.
a11y.announcements boolean true Set it to false, to disable screen reader announcements

Where:

interface Route {
	uri: string;
	path: string;
	meta: object;
	params: object;
}

interface Location {
	pathname: string;
	search: string;
	hash: string;
	state: object;
}

type CreateAnnouncement = (
	route: Route,
	location: Location,
) => string | Promise<string>;

interface HistorySource {
	readonly location: Location;
	addEventListener(event: "popstate", handler: () => void): void;
	removeEventListener(event: "popstate", handler: () => void): void;
	history: {
		readonly state: object;
		pushState(state: object, title: string, uri: string): void;
		replaceState(state: object, title: string, uri: string): void;
		go(to: number): void;
	};
}

Link

A component used to navigate around the application. It will automatically resolve the to path relative to the current Route and to the Routers basepath.

<Router>
	<Route path="blog/*">
		<Link to="svelte">Go to /blog/svelte</Link>
		<Link to="../profile">Go to /profile</Link>
	</Route>
</Router>
<Router basepath="/base">
	<Route path="blog/*">
		<Link to="svelte">Go to /base/blog/svelte</Link>
		<Link to="../profile">Go to /base/profile</Link>
	</Route>
</Router>
Properties
Property Type Default Value Description
to string URL the component should link to. It will be resolved relative to the current Route.
replace boolean false When true, clicking the Link will replace the current entry in the history stack instead of adding a new one.
state object {} An object that will be pushed to the history stack when the Link is clicked. A state is arbitrary data, that you don't want to communicate through the url, much like the body of a HTTP POST request.
getProps GetProps null A function that returns an object that will be spread on the underlying anchor element's attributes. The first argument given to the function is an object with the properties location, href, isPartiallyCurrent, isCurrent. Look at the NavLink component in the example project setup to see how you can build your own link components with this.

Where:

interface Location {
	pathname: string;
	search: string;
	hash: string;
	state: object;
}

type GetProps = ({
	location: Location;
	href: string;
	isPartiallyCurrent: boolean;
	isCurrent: boolean;
}) => object;

All other props will be passed to the underlying <a /> element. If the passed props and the props returned from getProps contain clashing keys, the values returned from getProps will be used.

Route

A component that will render its component property or children when its ancestor Router component decides it is the best match.

All properties other than path, component, meta and primary given to the Route will be passed to the rendered component.

A Route path can match parameters with "path/:parameterName" and wildcards with "path/*" or "path/*wildcardName". All parameters and wildcard values will be provided to the component as props. They can also be accessed inside a Route slot via let:params.

The Route component will also receive the current location, as well as the navigate function, that is scoped to the current Route as props. They can be accessed inside the Route slot, via let:location and let:navigate.

<!-- Both variants will do the same -->
<Route path="blog/:id" component="{BlogPost}" />
<Route path="blog/:id" let:params>
	<BlogPost id="{params.id}" />
</Route>

<!-- Access the current location inside the slot -->
<Route path="search" let:location>
	<BlogPost queryString="{location.search}" />
</Route>

<!--
  Navigate programatically using relative links
  (See also `navigate` and `useNavigate`)
-->
<Route path="search" let:navigate>
	<BlogPost {navigate} />
</Route>

<!--
  Routes without a path are default routes.
  They will match if no other Route could be matched
-->
<Route component="{Home}"></Route>

You can nest Routes, to easily define a routing structure for your app. Just remember to add a splat (*) to the end of the parent Routes path.

<!-- Don't forget the '*' -->
<Route path="blog/*">
	<!-- Render specific post with id "123" at /blog/post/123 -->
	<Route path="post/:id" component="{BlogPost}" />
	<!-- Index Route for /blog -->
	<Route path="/" component="{Favourites}" />
</Route>
<Route component="{Home}"></Route>

You can also provide a meta prop to a Route, that you can use to identify the Route for example, when providing a custom a11y.createAnnouncement function the the parent Router.

<script>
	import { Router, Route, Link } from "svelte-navigator";

	// Provide a custom message when navigating using
	// a routes `meta` information
	function createAnnouncement(route, location) {
		const viewName = route.meta.name;
		const { pathname } = location;
		return `Navigated to the ${viewName} view at ${pathname}`;
	}
</script>

<Router a11y="{{ createAnnouncement }}">
	<Link to="profile">Go to /profile</Link>
	<Route
		path="profile"
		component="{Profile}"
		meta="{{ name: 'user profile' }}"
	/>
	<Route path="blog/*" meta="{{ name: 'blog' }}">
		<Blog />
	</Route>
</Router>
Properties
Property Type Default Value Description
path string '' The path for when this component should be rendered. If no path is given the Route will act as the default that matches if no other Route in the Router matches.
component SvelteComponent null The component constructor that will be used for rendering when the Route matches. If component is not set, the children of Route will be rendered instead.
meta object {} An arbitrary object you can pass the Route, to later access it (for example in a11y.createAnnouncement).
primary boolean true If set to false, the parent Router will not manage focus for this Route or any child Routes.

Hooks

Svelte Navigator exposes a few React-esque hooks to access parts of the Routers context. These hooks must always be called during component initialization, because thats when Sveltes getContext must be called.

All navigator hooks return either a readable store you can subscibe to, or a function, that internally interacts with the Routers context.

useNavigate

A hook, that returns a context-aware version of navigate. It will automatically resolve the given link relative to the current Route.

<!-- App.svelte -->
<script>
	import { Router, Route } from "svelte-navigator";
	import RouteComponent from "./RouteComponent.svelte";
</script>

<Router>
	<Route path="routePath">
		<RouteComponent />
	</Route>
	<!-- ... -->
</Router>

<!-- RouteComponent.svelte -->
<script>
	import { useNavigate } from "svelte-navigator";

	const navigate = useNavigate();
</script>

<button on:click="{() => navigate('relativePath')}">
	go to /routePath/relativePath
</button>
<button on:click="{() => navigate('/absolutePath')}">
	go to /absolutePath
</button>

It will also resolve a link against the basepath of the Router

<!-- App.svelte -->
<Router basepath="/base">
	<Route path="routePath">
		<RouteComponent />
	</Route>
	<!-- ... -->
</Router>

<!-- RouteComponent.svelte -->
<script>
	import { useNavigate } from "svelte-navigator";

	const navigate = useNavigate();
</script>

<button on:click="{() => navigate('relativePath')}">
	go to /base/routePath/relativePath
</button>
<button on:click="{() => navigate('/absolutePath')}">
	go to /base/absolutePath
</button>

The returned navigate function is identical to the navigate prop, that is passed to a Routes component. useNavigates advantage is, that you can use it easily in deeply nested components.

<!-- App.svelte -->
<Router>
	<Route path="routeA" component="{RouteA}" />
	<Route path="routeB" let:navigate>
		<RouteB {navigate} />
	</Route>
	<Route path="routeC">
		<RouteC />
	</Route>
	<!-- ... -->
</Router>

<!-- All three components can use the navigate function in the same way -->
<!-- RouteA.svelte -->
<script>
	export let navigate;
</script>

<!-- RouteB.svelte -->
<script>
	export let navigate;
</script>

<!-- RouteC.svelte -->
<script>
	import { useNavigate } from "svelte-navigator";
	const navigate = useNavigate();
</script>

The returned navigate function accepts the same parameters as the global navigate function.

Parameters
Parameter Type Default Value Description
to string | number The path you want to navigate to. If to is a number, it is used to navigate in through the existing history stack, to the entry with the index currentStackIndex + to (navigate(-1) is equivalent to hitting the back button in your browser)
options object The navigation options
options.state object {} An arbitrary object, that will be pushed to the history state stack
options.replace boolean false If true, the current entry in the history stack will be replaced with the next navigation, instead of pushing the next navigation onto the stack

useLocation

Access the current location via a readable store and react to changes in location.

<!-- RouteComponent.svelte -->
<script>
	import { useLocation } from "svelte-navigator";

	const location = useLocation();

	$: console.log($location);
	/*
	  {
	    pathname: "/blog",
	    search: "?id=123",
	    hash: "#comments",
	    state: {}
	  }
	*/
</script>

useResolve

Resolve a given link relative to the current Route and the Routers basepath. It is used under the hood in Link and useNavigate. You can use it to manually resolve links, when using the link or links actions. (See link)

<script>
	import { link, useResolve } from "svelte-navigator";

	export let path;

	const resolve = useResolve();
	// `resolvedLink` will be resolved relative to its parent Route
	// and the Router `basepath`
	$: resolvedLink = resolve(path);
</script>

<a href="{resolvedLink}" use:link>Relative link</a>

Note, that you might need to re-resolve the link, to avoid stale links on location changes. You can achive this by deriving a store from the $location store, or by forcing Svelte to recompute the reactive resolvedLink variable, by passing $location as a second argument to resolve:

<script>
	import { link, useResolve, useLocation } from "svelte-navigator";

	export let path;

	const resolve = useResolve();
	const location = useLocation();
	// Force Svelte to re-run this assignement, when location changes
	$: resolvedLink = resolve(path, $location);
</script>

<a href="{resolvedLink}" use:link>Relative link</a>

useResolvable

Resolve a given link relative to the current Route and the Routers basepath. It works very similar to useResolve, but returns a store of the resolved path, that updates, when location changes. You will prabably want to use useResolvable, when the path you want to resolve does not change, and useResolve, when you're path is changing, for example, when you get it from a prop.

You can use useResolvable to manually resolve links, when using the link or links actions. (See link)

<script>
	import { link, useResolvable } from "svelte-navigator";

	// `resolvedLink` will be resolved relative to its parent Route
	// and the Router `basepath`
	const resolvedLink = useResolvable("relativePath");
</script>

<a href="{$resolvedLink}" use:link>Relative link</a>

useMatch

Use Svelte Navigators matching without needing to use a Route. Returns a readable store with the potential match, that changes, when the location changes.

<script>
	import { useMatch } from "svelte-navigator";

	const relativeMatch = useMatch("relative/path/:to/*somewhere");
	const absoluteMatch = useMatch("/absolute/path/:to/*somewhere");

	$: console.log($relativeMatch.params.to);
	$: console.log($absoluteMatch.params.somewhere);
</script>

useParams

Access the parent Routes matched params and wildcards via a readable store.

<!--
	Somewhere inside <Route path="user/:id/*splat" />
	with a current url of "/myApp/user/123/pauls-profile"
-->
<script>
	import { useParams } from "svelte-navigator";

	const params = useParams();

	$: console.log($params); // -> { id: "123", splat: "pauls-profile" }
</script>

<h3>Welcome user {$params.id}! bleep bloop...</h3>

useFocus

Provide a custom element to focus, when the parent route is visited. It returns the registerFocus action you can apply to an element via the use directive:

<!-- Somewhere inside a Route -->
<script>
	import { useFocus } from "svelte-navigator";

	const registerFocus = useFocus();
</script>

<h1>Don't worry about me...</h1>
<p use:registerFocus>Here, look at me!</p>

You can also use registerFocus asynchronously:

<!-- Somewhere inside a Route -->
<script>
	import { onMount } from "svelte";
	import { useFocus } from "svelte-navigator";

	const registerFocus = useFocus();

	const lazyImport = import("./MyComponent.svelte").then(
		module => module.default,
	);
</script>

{#await lazyImport then MyComponent}
<MyComponent {registerFocus} />
{/await}

<!-- MyComponent.svelte -->
<script>
	export let registerFocus;
</script>

<h1 use:registerFocus>Hi there!</h1>

You should however only use it asynchronously, if you know, that the focus element will register soon. Otherwise, focus will remain at the clicked link, and randomly change a few seconds later without explanation, which is a very bad experience for screen reader users.

When you need to wait for data, before you can render a component, you should consider providing a hidden heading, that informs a screen reader user about the current loading process.

<!-- Somewhere inside a Route -->
<script>
	import { onMount } from "svelte";
	import { useFocus } from "svelte-navigator";
	import BlogPost from "./BlogPost.svelte";

	const registerFocus = useFocus();

	const blogPostRequest = fetch("some/blog/post");
</script>

<style>
	.visuallyHidden {
		position: absolute;
		width: 1px;
		height: 1px;
		padding: 0;
		overflow: hidden;
		clip: rect(0, 0, 0, 0);
		white-space: nowrap;
		border: 0;
	}
</style>

{#await blogPostRequest}
<h1 class="visuallyHidden" use:registerFocus>
	The blog post is being loaded...
</h1>
{:then data}
<BlogPost {data} />
{/await}

Programmatic Navigation

Svelte Navigator exports a global navigate function, you can use to programmatically navigate around your application.

It will however not be able to perform relative navigation. Use the useNavigate hook instead.

If your using a custom history (for example with createMemorySource), the created history will have its own navigate function. Calling the globally exported function, will not work as intended.

If you're serving your app from a subdirectory or if you're using a custom history, it is not advised to use navigate. Use useNavigate instead.

navigate

A function that allows you to imperatively navigate around the application for those use cases where a Link component is not suitable, e.g. after submitting a form.

The first argument is a string denoting where to navigate to, and the second argument is an object with a replace and state property equivalent to those in the Link component.

Note that navigate does not have access to the Routers context, so it cannot automatically resolve relative links. You might prefer useNavigate instead.

<script>
	import { navigate } from "svelte-navigator";

	function onSubmit() {
		login().then(() => {
			navigate("/success", { replace: true });
		});
	}
</script>

If the first parameter to navigate is a number, it is used to navigate the history stack (for example for a browser like "go back/go forward" functionality).

<script>
	import { navigate } from "svelte-navigator";
</script>

<button on:click="{() => navigate(-1)}">Back</button>
<button on:click="{() => navigate(1)}">Forward</button>
Parameters
Parameter Type Default Value Description
to string | number The path you want to navigate to. If to is a number, it is used to navigate in through the existing history stack, to the entry with the index currentStackIndex + to (navigate(-1) is equivalent to hitting the back button in your browser)
options object The navigation options
options.state object {} An arbitrary object, that will be pushed to the history state stack
options.replace boolean false If true, the current entry in the history stack will be replaced with the next navigation, instead of pushing the next navigation onto the stack

Actions

You can use the link and links actions, to use standard <a href="..." /> elements for navigation.

link

An action used on anchor tags to navigate around the application. You can add an attribute replace to replace the current entry in the history stack instead of adding a new one.

<!-- App.svelte -->
<script>
	import { link, Route, Router } from "svelte-navigator";
	import RouteComponent from "./RouteComponent.svelte";
</script>

<Router>
	<a href="/" use:link>Home</a>
	<a href="/replace" use:link replace>Replace this URL</a>
	<!-- ... -->
</Router>

You should note that an action has no access to sveltes context, so links will not automatically be resolved on navigation. This will be a problem when you want to take advantage of Svelte Navigators relative navigation or when your app is served from a subdirectory. You can use the useResolve hook to resolve the link manually.

<script>
	import { link, useResolve } from "svelte-navigator";

	const resolve = useResolve();
	// `resolvedLink` will be "/route1/relativePath"
	const resolvedLink = resolve("relativePath");
</script>

<a href="{resolvedLink}" use:link>Relative link</a>

link uses the global navigate function by default, so if you're not using the default history mode (for example, memory mode or a custom history), navigating with it will not work as intended. To fix this, you could either use a Link component, or you can pass a custom navigate function to the action.

<!-- App.svelte -->
<script>
	import {
		link,
		Route,
		Router,
		createHistory,
		createMemorySource,
	} from "svelte-navigator";

	const memoryHistory = createHistory(createMemorySource());
	const { navigate } = memoryHistory;
</script>

<Router history="{memoryHistory}">
	<a href="/" use:link="{navigate}">Home</a>
	<!-- ... -->
</Router>

Because of the issues with link resolution and the dependency on the global navigation function, it is generally advised, not to use the link and links actions if you're not using a standard app, with all the default configuration.

links

An action used on a root element to make all relative anchor elements navigate around the application. You can add an attribute replace on any anchor to replace the current entry in the history stack instead of adding a new one. You can add an attribute noroute for this action to skip over the anchor and allow it to use the native browser action.

<!-- App.svelte -->
<script>
	import { links, Router } from "svelte-navigator";
</script>

<div use:links>
	<Router>
		<a href="/">Home</a>
		<a href="/replace" replace>Replace this URL</a>
		<a href="/native" noroute>Use the native action</a>
		<!-- ... -->
	</Router>
</div>

As with the link action, the href attribute of the used <a /> elements will not be resolved automatically.

If you're using a custom history, you need to pass its navigate function to the links function, just like you have to do with link.

Custom History

If you don't want to use the HTML5 History API for Navigation, you can use a custom history.

Svelte Navigator comes with a memory based history, you can use. It is practical for testing.

To create a custom history, pass a history source to the createHistory function.

You could use multiple Routers, that don't interfere with each other, by using a different history for each one.

<script>
	import { Router, createHistory, createMemorySource } from "svelte-navigator";

	const html5History = createHistory(window);
	const memoryHistory = createHistory(createMemorySource());
</script>

<Router history="{html5History}">
	<!-- I will function like the standard Router -->
</Router>

<Router history="{memoryHistory}">
	<!-- I store the history stack in memory -->
</Router>

For a more advanced example, checkout the Custom Hash History example.

License

MIT


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