dioxuslab/examples/rsx_usage.rs

236 lines
7.3 KiB
Rust

//! A tour of the rsx! macro
//! ------------------------
//!
//! This example serves as an informal quick reference of all the things that the rsx! macro can do.
//!
//! A full in-depth reference guide is available at: https://www.notion.so/rsx-macro-basics-ef6e367dec124f4784e736d91b0d0b19
//!
//! ### Elements
//! - Create any element from its tag
//! - Accept compile-safe attributes for each tag
//! - Display documentation for elements
//! - Arguments instead of String
//! - Text
//! - Inline Styles
//!
//! ## General Concepts
//! - Iterators
//! - Keys
//! - Match statements
//! - Conditional Rendering
//!
//! ### Events
//! - Handle events with the "onXYZ" syntax
//! - Closures can capture their environment with the 'a lifetime
//!
//!
//! ### Components
//! - Components can be made by specifying the name
//! - Components can be referenced by path
//! - Components may have optional parameters
//! - Components may have their properties specified by spread syntax
//! - Components may accept child nodes
//! - Components that accept "onXYZ" get those closures bump allocated
//!
//! ### Fragments
//! - Allow fragments using the built-in `Fragment` component
//! - Accept a list of vnodes as children for a Fragment component
//! - Allow keyed fragments in iterators
//! - Allow top-level fragments
//!
fn main() {
dioxus::desktop::launch(app);
}
/// When trying to return "nothing" to Dioxus, you'll need to specify the type parameter or Rust will be sad.
/// This type alias specifies the type for you so you don't need to write "None as Option<()>"
const NONE_ELEMENT: Option<()> = None;
use baller::Baller;
use dioxus::prelude::*;
fn app(cx: Scope) -> Element {
let formatting = "formatting!";
let formatting_tuple = ("a", "b");
let lazy_fmt = format_args!("lazily formatted text");
cx.render(rsx! {
div {
// Elements
div {}
h1 {"Some text"}
h1 {"Some text with {formatting}"}
h1 {"Formatting basic expressions {formatting_tuple.0} and {formatting_tuple.1}"}
h1 {"Formatting without interpolation " [formatting_tuple.0] "and" [formatting_tuple.1] }
h2 {
"Multiple"
"Text"
"Blocks"
"Use comments as separators in html"
}
div {
h1 {"multiple"}
h2 {"nested"}
h3 {"elements"}
}
div {
class: "my special div",
h1 {"Headers and attributes!"}
}
div {
// pass simple rust expressions in
class: lazy_fmt,
id: format_args!("attributes can be passed lazily with std::fmt::Arguments"),
div {
class: {
const WORD: &str = "expressions";
format_args!("Arguments can be passed in through curly braces for complex {}", WORD)
}
}
}
// Expressions can be used in element position too:
rsx!(p { "More templating!" }),
// Iterators
(0..10).map(|i| rsx!(li { "{i}" })),
// Iterators within expressions
{
let data = std::collections::HashMap::<&'static str, &'static str>::new();
// Iterators *should* have keys when you can provide them.
// Keys make your app run faster. Make sure your keys are stable, unique, and predictable.
// Using an "ID" associated with your data is a good idea.
data.into_iter().map(|(k, v)| rsx!(li { key: "{k}", "{v}" }))
}
// Matching
match true {
true => rsx!( h1 {"Top text"}),
false => rsx!( h1 {"Bottom text"})
}
// Conditional rendering
// Dioxus conditional rendering is based around None/Some. We have no special syntax for conditionals.
// You can convert a bool condition to rsx! with .then and .or
true.then(|| rsx!(div {})),
// Alternatively, you can use the "if" syntax - but both branches must be resolve to Element
if false {
rsx!(h1 {"Top text"})
} else {
rsx!(h1 {"Bottom text"})
}
// Using optionals for diverging branches
if true {
Some(rsx!(h1 {"Top text"}))
} else {
None
}
// returning "None" without a diverging branch is a bit noisy... but rare in practice
None as Option<()>,
// Use the Dioxus type-alias for less noise
NONE_ELEMENT,
// can also just use empty fragments
Fragment {}
// Fragments let you insert groups of nodes without a parent.
// This lets you make components that insert elements as siblings without a container.
div {"A"}
Fragment {
div {"B"}
div {"C"}
Fragment {
"D"
Fragment {
"E"
"F"
}
}
}
// Components
// Can accept any paths
// Notice how you still get syntax highlighting and IDE support :)
Baller {}
baller::Baller { }
crate::baller::Baller {}
// Can take properties
Taller { a: "asd" }
// Can take optional properties
Taller { a: "asd" }
// Can pass in props directly as an expression
{
let props = TallerProps {a: "hello", children: Default::default()};
rsx!(Taller { ..props })
}
// Spreading can also be overridden manually
Taller {
..TallerProps { a: "ballin!", children: Default::default() },
a: "not ballin!"
}
// Can take children too!
Taller { a: "asd", div {"hello world!"} }
// Components can be used with the `call` syntax
// This component's props are defined *inline* with the `inline_props` macro
with_inline(
text: "using functionc all syntax"
)
// helper functions
// Single values must be wrapped in braces or `Some` to satisfy `IntoIterator`
[helper(&cx, "hello world!")]
}
})
}
fn helper<'a>(cx: &'a ScopeState, text: &str) -> Element<'a> {
cx.render(rsx! {
p { "{text}" }
})
}
mod baller {
use super::*;
#[derive(Props, PartialEq)]
pub struct BallerProps {}
#[allow(non_snake_case)]
/// This component totally balls
pub fn Baller(_: Scope<BallerProps>) -> Element {
todo!()
}
}
#[derive(Props)]
pub struct TallerProps<'a> {
/// Fields are documented and accessible in rsx!
a: &'static str,
children: Element<'a>,
}
/// Documention for this component is visible within the rsx macro
#[allow(non_snake_case)]
pub fn Taller<'a>(cx: Scope<'a, TallerProps<'a>>) -> Element {
cx.render(rsx! {
&cx.props.children
})
}
#[inline_props]
fn with_inline<'a>(cx: Scope<'a>, text: &'a str) -> Element {
cx.render(rsx! {
p { "{text}" }
})
}