live-component

LiveComponent

TwigComponents that re-render dynamically via AJAX. Build reactive UIs in PHP + Twig with zero JavaScript. Every user interaction triggers a server round-trip that re-renders the component and morphs the DOM.

When to Use LiveComponent

Use LiveComponent when a component's output depends on user interaction -- search results that update as you type, forms with real-time validation, filters that refine a list, anything where the UI needs to change based on user input and that change requires server-side data or logic.

If the component never re-renders after initial load, use TwigComponent instead (less overhead, no AJAX). If the interaction is purely client-side (toggle, animation), use Stimulus instead.

Installation

composer require symfony/ux-live-component

Quick Reference

#[AsLiveComponent]           Make component live (re-renderable via AJAX)
#[LiveProp]                  State that persists across re-renders
#[LiveProp(writable: true)]  State that the frontend can modify
#[LiveAction]                Server method callable from frontend
data-model="prop"            Two-way bind input to LiveProp
data-action="live#action"    Call LiveAction on event
data-loading="..."           Show/hide/style elements during AJAX
{{ attributes }}             REQUIRED on root element (wires the Stimulus controller)

Basic Example

// src/Twig/Components/Counter.php
namespace App\Twig\Components;

use Symfony\UX\LiveComponent\Attribute\AsLiveComponent;
use Symfony\UX\LiveComponent\Attribute\LiveProp;
use Symfony\UX\LiveComponent\Attribute\LiveAction;
use Symfony\UX\LiveComponent\DefaultActionTrait;

#[AsLiveComponent]
final class Counter
{
    use DefaultActionTrait;

    #[LiveProp]
    public int $count = 0;

    #[LiveAction]
    public function increment(): void
    {
        $this->count++;
    }

    #[LiveAction]
    public function decrement(): void
    {
        $this->count--;
    }
}

{# templates/components/Counter.html.twig #}
<div {{ attributes }}>
    <button data-action="live#action" data-live-action-param="decrement">-</button>
    <span>{{ count }}</span>
    <button data-action="live#action" data-live-action-param="increment">+</button>
</div>