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HTML

              
                <div class="min-h-screen p-16 bg-gray-100">
<!-- Check out a version without all the code -->
<!-- https://codepen.io/KevinBatdorf/pen/PoZOZPe -->
<!-- https://github.com/KevinBatdorf/alpine-observe-other-components -->
	
<h1 class="text-2xl font-bold mb-2">Find the total</h1>

<!-- This is it. No custom events -->
<div id="alpine-watcher" x-data="counterObserver()" x-init="start()" class="mb-6">
	<p>Total: <span x-text="total"></span></p>
</div>


<p class="mb-6 max-w-lg">
	Each box below is a separate Alpine component. There are no events being fired but you can observe the updates and react to them using a mutation observer.
	<!-- One event just to reset the demo 🚀 -->
	<button x-data="{}" @click="$dispatch('reset', {})" class="underline">Reset</button>
</p>
	
<!-- This is a generic component that just generates 9 child components  -->
<div x-data="{ buttons: 9 }" class="grid md:grid-cols-2 lg:grid-cols-3 gap-10 max-w-lg">
	<template x-for="buttons in Array.from({ length: buttons })">
		<!-- These are all independant components -->
		<button
			x-data="counter()" @click="count++" @reset.window="count = 0" x-text="count"
			class="bg-indigo-500 h-20 shadow-lg text-white font-extrabold text-4xl flex flex-col items-center justify-center uppercase">
		</button>
	</template>
</div>

	
</div>

              
            
!

CSS

              
                [x-cloak] { display: none; }
              
            
!

JS

              
                
function counter() {
	return {
		count: 0
	}
}

function counterObserver() {
	return {
		total: 0,
		alpines: [],
		observer: null,
		start() {
			// Use an ID or another selector to focus on the components you want to ignore
			// Parent components can't be ignored though, so you might want additional logic
			// to ensure you have the correct components
			this.alpines = document.querySelectorAll('[x-data]:not(#alpine-watcher)')
			this.observer = new MutationObserver(mutations => {
				// Everytime a mutation occurs we can run a function
				this.updateTotalCount()
			})
			// Each Alpine needs to be observed separately
			this.alpines && this.wrapAlpines()
		},
		wrapAlpines() {
			this.alpines.forEach(alpine => {
				this.observer.observe(alpine, {
					attributes: true,
					childList: true,
					subtree: true,
				})
			})
		},
		updateTotalCount() {
			// Refresh the Alpine components and grab the data
			this.alpines = document.querySelectorAll('[x-data]:not(#alpine-watcher)')
			this.total = Array.from(this.alpines).map(alpine => {
				// This is an internal method where we can get the data.
				// Just be warned that this functionality could change
				// inside Alpine without notice
				return alpine.__x.getUnobservedData().count
				// We're filtering out 'undefined' values, specifically
				// the components that don't have 'count'
			}).filter(Boolean).reduce((a, b) => a + b, 0)
		},
	}
}
              
            
!
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