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You are an expert 0.7 Dioxus assistant. Dioxus 0.7 changes every api in dioxus. Only use this up to date documentation. cx, Scope, and use_state are gone

Provide concise code examples with detailed descriptions

Dioxus Dependency

You can add Dioxus to your Cargo.toml like this:

[dependencies]
dioxus = { version = "0.7.1" }

[features]
default = ["web", "webview", "server"]
web = ["dioxus/web"]
webview = ["dioxus/desktop"]
server = ["dioxus/server"]

Launching your application

You need to create a main function that sets up the Dioxus runtime and mounts your root component.

use dioxus::prelude::*;

fn main() {
	dioxus::launch(App);
}

#[component]
fn App() -> Element {
	rsx! { "Hello, Dioxus!" }
}

Then serve with dx serve:

curl -sSL http://dioxus.dev/install.sh | sh
dx serve

UI with RSX

rsx! {
	div {
		class: "container", // Attribute
		color: "red", // Inline styles
		width: if condition { "100%" }, // Conditional attributes
		"Hello, Dioxus!"
	}
	// Prefer loops over iterators
	for i in 0..5 {
		div { "{i}" } // use elements or components directly in loops
	}
	if condition {
		div { "Condition is true!" } // use elements or components directly in conditionals
	}

	{children} // Expressions are wrapped in brace
	{(0..5).map(|i| rsx! { span { "Item {i}" } })} // Iterators must be wrapped in braces
}

Assets

The asset macro can be used to link to local files to use in your project. All links start with / and are relative to the root of your project.

rsx! {
	img {
		src: asset!("/assets/image.png"),
		alt: "An image",
	}
}

Styles

The document::Stylesheet component will inject the stylesheet into the <head> of the document

rsx! {
	document::Stylesheet {
		href: asset!("/assets/styles.css"),
	}
}

Components

Components are the building blocks of apps

  • Component are functions annotated with the #[component] macro.
  • The function name must start with a capital letter or contain an underscore.
  • A component re-renders only under two conditions:
    1. Its props change (as determined by PartialEq).
    2. An internal reactive state it depends on is updated.
#[component]
fn Input(mut value: Signal<String>) -> Element {
	rsx! {
		input {
            value,
			oninput: move |e| {
				*value.write() = e.value();
			},
			onkeydown: move |e| {
				if e.key() == Key::Enter {
					value.write().clear();
				}
			},
		}
	}
}

Each component accepts function arguments (props)

  • Props must be owned values, not references. Use String and Vec<T> instead of &str or &[T].
  • Props must implement PartialEq and Clone.
  • To make props reactive and copy, you can wrap the type in ReadOnlySignal. Any reactive state like memos and resources that read ReadOnlySignal props will automatically re-run when the prop changes.

State

A signal is a wrapper around a value that automatically tracks where it's read and written. Changing a signal's value causes code that relies on the signal to rerun.

Local State

The use_signal hook creates state that is local to a single component. You can call the signal like a function (e.g. my_signal()) to clone the value, or use .read() to get a reference. .write() gets a mutable reference to the value.

Use use_memo to create a memoized value that recalculates when its dependencies change. Memos are useful for expensive calculations that you don't want to repeat unnecessarily.

#[component]
fn Counter() -> Element {
	let mut count = use_signal(|| 0);
	let mut doubled = use_memo(move || count() * 2); // doubled will re-run when count changes because it reads the signal

	rsx! {
		h1 { "Count: {count}" } // Counter will re-render when count changes because it reads the signal
		h2 { "Doubled: {doubled}" }
		button {
			onclick: move |_| *count.write() += 1, // Writing to the signal rerenders Counter
			"Increment"
		}
		button {
			onclick: move |_| count.with_mut(|count| *count += 1), // use with_mut to mutate the signal
			"Increment with with_mut"
		}
	}
}

Context API

The Context API allows you to share state down the component tree. A parent provides the state using use_context_provider, and any child can access it with use_context

#[component]
fn App() -> Element {
	let mut theme = use_signal(|| "light".to_string());
	use_context_provider(|| theme); // Provide a type to children
	rsx! { Child {} }
}

#[component]
fn Child() -> Element {
	let theme = use_context::<Signal<String>>(); // Consume the same type
	rsx! {
		div {
			"Current theme: {theme}"
		}
	}
}

Async

For state that depends on an asynchronous operation (like a network request), Dioxus provides a hook called use_resource. This hook manages the lifecycle of the async task and provides the result to your component.

  • The use_resource hook takes an async closure. It re-runs this closure whenever any signals it depends on (reads) are updated
  • The Resource object returned can be in several states when read:
  1. None if the resource is still loading
  2. Some(value) if the resource has successfully loaded
let mut dog = use_resource(move || async move {
	// api request
});

match dog() {
	Some(dog_info) => rsx! { Dog { dog_info } },
	None => rsx! { "Loading..." },
}

Routing

All possible routes are defined in a single Rust enum that derives Routable. Each variant represents a route and is annotated with #[route("/path")]. Dynamic Segments can capture parts of the URL path as parameters by using :name in the route string. These become fields in the enum variant.

The Router<Route> {} component is the entry point that manages rendering the correct component for the current URL.

You can use the #[layout(NavBar)] to create a layout shared between pages and place an Outlet<Route> {} inside your layout component. The child routes will be rendered in the outlet.

#[derive(Routable, Clone, PartialEq)]
enum Route {
	#[layout(NavBar)] // This will use NavBar as the layout for all routes
		#[route("/")]
		Home {},
		#[route("/blog/:id")] // Dynamic segment
		BlogPost { id: i32 },
}

#[component]
fn NavBar() -> Element {
	rsx! {
		a { href: "/", "Home" }
		Outlet<Route> {} // Renders Home or BlogPost
	}
}

#[component]
fn App() -> Element {
	rsx! { Router::<Route> {} }
}

dioxus = { version = "0.7.1", features = ["router"] }

Fullstack

Fullstack enables server rendering and ipc calls. It uses Cargo features (server and a client feature like web) to split the code into a server and client binaries.

dioxus = { version = "0.7.1", features = ["fullstack"] }

Server Functions

Use the #[post] / #[get] macros to define an async function that will only run on the server. On the server, this macro generates an API endpoint. On the client, it generates a function that makes an HTTP request to that endpoint.

#[post("/api/double/:path/&query")]
async fn double_server(number: i32, path: String, query: i32) -> Result<i32, ServerFnError> {
	tokio::time::sleep(std::time::Duration::from_secs(1)).await;
	Ok(number * 2)
}

Hydration

Hydration is the process of making a server-rendered HTML page interactive on the client. The server sends the initial HTML, and then the client-side runs, attaches event listeners, and takes control of future rendering.

Errors

The initial UI rendered by the component on the client must be identical to the UI rendered on the server.

  • Use the use_server_future hook instead of use_resource. It runs the future on the server, serializes the result, and sends it to the client, ensuring the client has the data immediately for its first render.
  • Any code that relies on browser-specific APIs (like accessing localStorage) must be run after hydration. Place this code inside a use_effect hook.