dioxus/packages/core/examples/borrowed.rs
2021-03-03 11:13:46 -05:00

191 lines
4.4 KiB
Rust

//! Demonstrate that borrowed data is possible as a property type
//! Borrowing (rather than cloning) is very important for speed and ergonomics.
//!
//! It's slightly more advanced than just cloning, but well worth the investment.
//!
//! If you use the FC macro, we handle the lifetimes automatically, making it easy to write efficient & performant components.
fn main() {}
use dioxus_core::prelude::*;
struct Props {
items: Vec<ListItem>,
}
struct ListItem {
name: String,
age: u32,
}
fn app(ctx: Context, props: &Props) -> DomTree {
let (f, setter) = use_state(&ctx, || 0);
ctx.render(move |b| {
let mut root = builder::ElementBuilder::new(b, "div");
for child in &props.items {
// notice that the child directly borrows from our vec
// this makes lists very fast (simply views reusing lifetimes)
root = root.child(builder::virtual_child(
b.bump,
ChildProps {
item: child,
item_handler: setter,
},
// <ChildItem item=child hanldler=setter />
child_item,
));
}
root.finish()
})
}
type StateSetter<T> = dyn Fn(T);
struct ChildProps<'a> {
// Pass down complex structs
item: &'a ListItem,
// Even pass down handlers!
item_handler: &'a StateSetter<i32>,
}
fn child_item(ctx: Context, props: &ChildProps) -> DomTree {
todo!()
// ctx.render(rsx! {
// div {
// item: child,
// handler: setter,
// abc: 123,
// onclick: props.item_handler,
// h1 { "abcd123" }
// h2 { "abcd123" }
// div {
// "abcd123"
// h2 { }
// p { }
// },
// }
// })
}
/*
rsx! {
ChildItem {
// props
item: child, handler: setter,
// children
div { class:"abcd", abc: 123 },
div { class:"abcd", abc: 123 },
// Auto-text coercion
"eyo matie {abc}",
// Anything that accepts Into<VChild>
{},
}
}
// dreaming of this syntax
#[derive(Properties)]
struct ChildProps<'a> {
username: &'a str,
item_handler: &'a dyn Fn(i32),
}
fn child_item(ctx: Context, props: &ChildProps) -> DomTree {
ctx.render(rsx! {
div {
class: "abc123",
abc: 123,
onclick: props.item_handler,
h1 { "Hello, {props.username}!" },
h2 { "Welcome the RSX syntax" },
div {
h3 { "This is a subheader" }
button {
onclick: props.handler,
"This is a button"
}
"This is child text"
},
}
})
}
// This is also nice
#[dioxus::component]
static CHILD: FC = |ctx, username: &str, handler: &dyn Fn(i32)| {
ctx.render(rsx! {
div {
class: "abc123",
abc: 123,
onclick: handler,
h1 { "Hello, {username}!" },
h2 { "Welcome the RSX syntax" },
div {
h3 { "This is a subheader" }
button {
onclick: props.handler,
"This is a button"
}
"This is child text"
},
}
})
}
Menlo, Monaco, 'Courier New', monospace
struct Item {
name: String,
content: String,
}
#[dioxus::live_component]
static CHILD: FC = |ctx, username: &str, handler: &dyn Fn(i32)| {
// return lazy nodes or
let ssr = ctx.suspend(async {
let data = fetch("https://google.com")
.await?
.json::<Item>()
.await?;
rsx! {
div {
h1 { "Welcome: {data.name}" }
p { "Content: \n {data.content}" }
}
}
});
ctx.render(rsx! {
div {
class: "abc123",
abc: 123,
onclick: handler,
h1 { "Hello, {username}!" },
h2 { "Welcome the RSX syntax" },
div {
h3 { "This is a subheader" }
button {
onclick: props.handler,
"This is a button"
}
{ssr}
},
}
})
}
*/