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34 lines
1.0 KiB
34 lines
1.0 KiB
6 years ago
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---
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title: Event forwarding
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---
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Unlike DOM events, component events don't *bubble*. If you want to listen to an event on some deeply nested component, the intermediate components must *forward* the event.
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In this case, we have the same `App.svelte` and `Inner.svelte` as in the [previous chapter](tutorial/component-events), but there's now an `Outer.svelte` component that contains `<Inner/>`.
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One way we could solve the problem is adding `createEventDispatcher` to `Outer.svelte`, listening for the `message` event, and creating a handler for it:
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```html
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<script>
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import Inner from './Inner.svelte';
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import { createEventDispatcher } from 'svelte';
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const dispatch = createEventDispatcher();
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function forward(event) {
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dispatch('message', event.detail);
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}
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</script>
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<Inner on:message={forward}/>
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```
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But that's a lot of code to write, so Svelte gives us an equivalent shorthand — an `on:message` event directive without a value means 'forward all `message` events'.
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```html
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<script>
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import Inner from './Inner.svelte';
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</script>
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<Inner on:message/>
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```
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