57 lines
1.3 KiB
Markdown
57 lines
1.3 KiB
Markdown
# Dioxus Signals
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Dioxus Signals is an ergonomic Copy runtime for data with local subscriptions in Dioxus.
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## Copy Data
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All signals implement Copy, even if the inner value does not implement copy. This makes it easy to move any data into futures or children.
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```rust
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fn App(cx: Scope) -> Element {
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let signal = use_signal(cx, || "hello world".to_string());
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spawn(async move {
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// signal is Copy even though String is not copy
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signal
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});
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render! {
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"{signal}"
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}
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}
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```
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## Local Subscriptions
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Signals will only subscribe to components when you read from the signal in that component. It will never subscribe to a component when reading data in a future or event handler.
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```rust
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fn app(cx: Scope) -> Element {
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// Because signal is never read in this component, this component will not rerun when the signal changes
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let signal = use_signal(cx, || 0);
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render! {
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onclick: move |_| {
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*signal.write() += 1;
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}
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for id in 0..10 {
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Child {
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signal: signal,
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}
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}
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}
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}
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#[derive(Props, Clone, PartialEq)]
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struct ChildProps {
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signal: Signal<usize>,
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}
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fn Child(cx: Scope<ChildProps>) -> Element {
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// This component does read from the signal, so when the signal changes it will rerun
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render! {
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"{cx.props.signal}"
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}
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}
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```
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