src/widgets/LocationFormWidget.php
protected function country()
    {
        $this->parts['{country}'] = $this->form->field($this->model, $this->model->getCountryPropertyName(), ['options' => ['class' => 'form-group']])->dropDownList(
                ArrayHelper::map(Country::find()->orderBy(['name' => SORT_ASC])->all(), 'id', 'name'), [
            'id' => $this->fieldIds['country']
            , 'prompt' => Yii::t('jlorente/location', 'Select country')
            , 'name' => $this->getSubmitModelName($this->model->getCountryPropertyName())
        ]);
    }
protected function country()
    {
        $this->parts['{country}'] = $this->form->field($this->model, $this->model->getCountryPropertyName(), ['options' => ['class' => 'form-group']])->dropDownList(
                ArrayHelper::map(Country::find()->orderBy(['name' => SORT_ASC])->all(), 'id', 'name'), [
            'id' => $this->fieldIds['country']
            , 'prompt' => Yii::t('jlorente/location', 'Select country')
            , 'name' => $this->getSubmitModelName($this->model->getCountryPropertyName())
        ]);
    }
Renders the country part.