How to select checkbox when changing data Yii2?

Question

PHP

There is a form

<?=$f->field($flora_user, 'user_id')->checkBoxList(ArrayHelper::map($user,'id','fio'))->label('Автор(ы):')?>

$floraUser = new floraUser();
$user = User::find()->all();

floraUser is an intermediate table
When opening a form for changing data, it is necessary to mark the necessary checkboxes that were marked when adding.
If you do this, then you get an array and the error Call to a member function isAttributeRequired() on array
$floraUser = $this->findModel($id)->users;

findModel($id)
    {
        if (($model = Flora::findOne($id)) !== null) {
            return $model;
}

connections

public function getFloraUsers()
    {
        return $this->hasMany(FloraUser::className(), ['flora_id' => 'id']);
    }

    /**
     * @return \yii\db\ActiveQuery
     */
    public function getUsers()
    {
        return $this->hasMany(User::className(), ['id' => 'user_id'])->viaTable('flora_user', ['flora_id' => 'id']);
    }

Answer 1

exec will just execute the query, use getAll/getRow/getCol/getCell/getAssoc to get the results.

Answer 2

<?= $f->field($flora, 'users')
->checkBoxList(User::find()->select(['name', 'id'])->indexBy('id')->column())
->label('Автор(ы):') ?>