Livewire子组件值为Null：表单提交后父组件值非空子组件为空

提交表单后，父组件输入值正常，但调用<livewire:include-service>子组件时，父组件的include_service_title属性输出为Null，这是因为Livewire父子组件默认不会自动共享属性，父组件无法直接访问子组件的内部属性，需通过以下正确方式实现数据传递：

解决方案1：通过双向绑定（wire:model）传递数据 #

步骤1：配置子组件 #

子组件（IncludeService.php）中声明公开属性，并在视图中绑定该属性：
子组件类代码：

// Livewire 3
namespace App\Livewire;

use Livewire\Component;

class IncludeService extends Component
{
    #[Livewire\Attributes\PublicProperty]
    public $include_service_title = '';

    public function render()
    {
        return view('livewire.include-service');
    }
}

// Livewire 2
namespace App\Http\Livewire;

use Livewire\Component;

class IncludeService extends Component
{
    public $include_service_title = '';

    public function render()
    {
        return view('livewire.include-service');
    }
}

子组件视图代码（resources/views/livewire/include-service.blade.php）：

<label class="label_title">{{ __('Include Service Title') }}</label>
<input class="form--control" type="text" wire:model.defer="include_service_title">

步骤2：父组件绑定子组件属性 #

父组件视图中引用子组件时，通过wire:model.defer绑定到父组件的同名属性：

<!-- child component -->
<div class="row g-4">
    <div class="col-lg-4 col-sm-6">
        <div class="single-info-input">
            <livewire:include-service wire:model.defer="include_service_title">
        </div>
    </div>
</div>

父组件类中声明对应的属性：

// 父组件类
public $title = '';
public $include_service_title = '';

public function serviceStore()
{      
    dd($this->include_service_title);
}

解决方案2：通过事件传递数据 #

若不需要双向绑定，可通过Livewire事件机制传递数据：

步骤1：子组件触发事件 #

在子组件中添加方法触发事件，传递属性值：

// 子组件类
public function emitTitle()
{
    $this->dispatch('includeServiceTitleUpdated', title: $this->include_service_title);
}

可在子组件视图的输入框添加wire:change="emitTitle"实时触发，或在父组件提交前触发。

步骤2：父组件监听事件并更新属性 #

父组件中监听事件，接收子组件传递的数据：

// 父组件类
public $title = '';
public $include_service_title = '';

protected $listeners = ['includeServiceTitleUpdated' => 'updateIncludeServiceTitle'];

public function updateIncludeServiceTitle($title)
{
    $this->include_service_title = $title;
}

public function serviceStore()
{      
    dd($this->include_service_title);
}

内容的提问来源于stack exchange，提问作者Hasibur Rahman