单击添加按钮时，Yii2动态表单不会添加新字段

use yii\helpers\Html;
use yii\widgets\ActiveForm;
use yii\bootstrap\Button;
use yii\web\JsExpression;

/* @var $this yii\web\View */
/* @var $model app\models\YourModel */
/* @var $form yii\widgets\ActiveForm */

$this->registerJsFile('@web/js/jquery.js', ['depends' => [\yii\web\JqueryAsset::class]]);
$this->registerJsFile('@web/js/yii.js', ['depends' => [\yii\web\JqueryAsset::class]]);
$this->registerJsFile('@web/js/yii.activeForm.js', ['depends' => [\yii\web\JqueryAsset::class]]);

<?php $form = ActiveForm::begin(['id' => 'dynamic-form']); ?>

<!-- 表单字段 -->

<div class="form-group">
    <?= Html::button('添加字段', ['class' => 'btn btn-success', 'id' => 'add-field-button']) ?>
</div>

<?php ActiveForm::end(); ?>

<?php
$js = <<<JS
    var index = 0;
    $('#add-field-button').on('click', function() {
        var template = '<div class="form-group">' +
            '<label class="control-label">新字段</label>' +
            '<input type="text" class="form-control" name="YourModel[newFields][' + index + ']" />' +
            '</div>';
        $('#dynamic-form').append(template);
        index++;
    });
JS;

$this->registerJs($js);
?>

public function actionCreate()
{
    $model = new YourModel();

    if ($model->load(Yii::$app->request->post()) && $model->save()) {
        // 保存成功后的操作
        return $this->redirect(['view', 'id' => $model->id]);
    }

    return $this->render('create', [
        'model' => $model,
    ]);
}