offline docs

offline-docs/alpinejs/magics/dispatch.md

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+# Alpine.js Documentation - Magics
+
+Magics are special properties that are available inside Alpine expressions. They provide convenient access to common functionality.
+
+## [$dispatch](/magics/dispatch)
+
+`$dispatch` is a helpful shortcut for dispatching browser events.
+
+```
+<div @notify="alert('Hello World!')">
+
+
+n<button @click="$dispatch('notify')">
+
+
+nNotify
+
+
+n</button>
+
+
+n</div>
+```
+
+You can also pass data along with the dispatched event if you wish. This data will be accessible as the `.detail` property of the event:
+
+```
+<div @notify="alert($event.detail.message)">
+
+
+n<button @click="$dispatch('notify', { message: 'Hello World!' })">
+
+
+nNotify
+
+
+n</button>
+
+
+n</div>
+```
+
+Under the hood, `$dispatch` is a wrapper for the more verbose API: `element.dispatchEvent(new CustomEvent(...))`
+
+**Note on event propagation**
+
+Notice that, because of [event bubbling](https://en.wikipedia.org/wiki/Event_bubbling), when you need to capture events dispatched from nodes that are under the same nesting hierarchy, you'll need to use the [`.window`](https://github.com/alpinejs/alpine#x-on) modifier:
+
+**Example:**
+
+```
+<!-- 🚫 Won't work -->
+
+
+n<div x-data>
+
+
+n<span @notify="..."></span>
+
+
+n<button @click="$dispatch('notify')">Notify</button>
+
+
+n</div>
+
+
+n<!-- ✅ Will work (because of .window) -->
+
+
+n<div x-data>
+
+
+n<span @notify.window="..."></span>
+
+
+n<button @click="$dispatch('notify')">Notify</button>
+
+
+n</div>
+```
+
+> The first example won't work because when `notify` is dispatched, it'll propagate to its common ancestor, the `div`, not its sibling, the `<span>`. The second example will work because the sibling is listening for `notify` at the `window` level, which the custom event will eventually bubble up to.
+
+### [Dispatching to other components](#dispatching-to-components)
+
+You can also take advantage of the previous technique to make your components talk to each other:
+
+**Example:**
+
+```
+<div
+
+
+nx-data="{ title: 'Hello' }"
+
+
+n@set-title.window="title = $event.detail"
+
+
+n>
+
+
+nh1 x-text="title"></h1>
+
+
+n</div>
+
+
+n<div x-data>
+
+
+n<button @click="$dispatch('set-title', 'Hello World!')">Click me</button>
+
+
+n</div>
+
+
+n<!-- When clicked, the content of the h1 will set to "Hello World!. -->
+```
+
+### [Dispatching to x-model](#dispatching-to-x-model)
+
+You can also use `$dispatch()` to trigger data updates for `x-model` data bindings. For example:
+
+```
+<div x-data="{ title: 'Hello' }">
+
+
+n<span x-model="title">
+
+
+n<button @click="$dispatch('input', 'Hello World!')">Click me</button>
+
+
+n<!-- After the button is pressed, `x-model` will catch the bubbling "input" event, and update title. -->
+
+
+n</span>
+
+
+n</div>
+```
+
+This opens up the door for making custom input components whose value can be set via `x-model`.
+
+Code highlighting provided by [Torchlight](https://torchlight.dev/)