48 lines
1.3 KiB
Markdown
48 lines
1.3 KiB
Markdown
# Signals
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Signals provide a way of forcing updates directly through Dioxus without having to go through the diffing phase.
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When diffing is too slow for your use-case, signals can be faster. Signals run at a higher priority than regular diffing, acting as a hint to Dioxus that a signal update needs to take precedence over a subtree update. This can be useful in real-time systems where getting data from a websocket to the screen ASAP is extremely important.
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- High
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- Medium
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- Low
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## Signals:
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Producer -> Receiver
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- The Dioxus VirtualDOM provides built-in receivers for signals.
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- Elements themselves act as receivers.
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- Any use of a signal schedules the current element and its children for updates.
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- Attributes are valid receivers
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- Text nodes are valid receivers
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- Receivers may not be passed into child components (must be de-referenced)
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- When receivers are derefed in a component's properties, the props will be updated in place and the component will re-render with the new value.
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```rust
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let sig = use_signal(|| 0);
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// any updates to the signal will cause the child to re-render completely
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Comp {
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prop: *sig
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}
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```
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Using 3 separate signals
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```rust
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let width = use_signal(|| 0);
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cx.request_next_frame(move |frame| async {
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sig1 += 1;
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frame.again();
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})
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div {
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h2 { "{sig1}" }
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h3 { "{sig2}" }
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h4 { "{sig3}" }
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}
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```
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