macgyer\yii2materializecss\widgets\Modal::initDefaults PHP Method

    protected function initDefaults()
    {
        switch ($this->modalType) {
            case self::TYPE_FIXED_FOOTER:
                Html::addCssClass($this->options, ['modalType' => 'modal-fixed-footer']);
                break;
            case self::TYPE_BOTTOM_SHEET:
                Html::addCssClass($this->options, ['modalType' => 'bottom-sheet']);
                break;
            default:
                break;
        }
        Html::addCssClass($this->options, ['widget' => 'modal']);
        if ($this->closeButton !== false) {
            $this->closeButton = ArrayHelper::merge(['class' => 'modal-close'], $this->closeButton);
        }
        if ($this->toggleButton !== false) {
            $this->toggleButton = ArrayHelper::merge(['class' => 'modal-trigger btn'], $this->toggleButton);
        }
        if ($this->clientOptions !== false) {
            $this->clientOptions = ArrayHelper::merge(['show' => false], $this->clientOptions);
        }
    }