Yii2 set hidden input as current user id - yii2

Question

I'm trying to set a form field as the id of the current logged in user using Yii2.
This is my form:
<?php $form = ActiveForm::begin();?>
<?= Html::activeHiddenInput($model, 'id', array('value'=> $model->getId()));?>
<?= $form->field($model, 'offer_type_id') ?>
<?= $form->field($model, 'offer_description')->textArea(['rows' => 6]) ?>
<?= $form->field($model, 'start_date') ?>
<?= $form->field($model, 'end_date') ?>
<?= $form->field($model, 'store_id') ?>
<div class="form-group">
<?= Html::submitButton('Submit', ['class' => 'btn btn-primary']) ?>
</div>
<?php ActiveForm::end(); ?>
and this is my model:
use Yii;
use yii\web\IdentityInterface;
/**
* This is the model class for table "tbl_offers".
*
* #property integer $offer_id
* #property integer $id
* #property integer $offer_type_id
* #property string $offer_description
* #property string $start_date
* #property string $end_date
* #property integer $store_id
*/
class TblOffers extends \yii\db\ActiveRecord implements IdentityInterface
{
public static function findIdentity($id)
{
return static::findOne($id);
}
public static function findIdentityByAccessToken($token, $type = null)
{
return static::findOne(['access_token' => $token]);
}
public function getId()
{
return $this->id;
}
public function getAuthKey()
{
return $this->authKey;
}
public function validateAuthKey($authKey)
{
return $this->authKey === $authKey;
}
/**
* #inheritdoc
*/
public static function tableName()
{
return 'tbl_offers';
}
/**
* #inheritdoc
*/
public function rules()
{
return [
[[ 'id', 'offer_type_id', 'offer_description', 'start_date', 'end_date', 'store_id'], 'required'],
[[ 'id', 'offer_type_id', 'store_id'], 'integer'],
[['start_date', 'end_date'], 'safe'],
[['offer_description'], 'string', 'max' => 8000]
];
}
/**
* #inheritdoc
*/
public function attributeLabels()
{
return [
'id' => 'ID',
'offer_type_id' => 'Offer Type ID',
'offer_description' => 'Offer Description',
'start_date' => 'Start Date',
'end_date' => 'End Date',
'store_id' => 'Store ID',
];
}
public function getofferId()
{
return $this->getPrimaryKey();
}
}
Any ideas as to where I'm going wrong? When I try to save the form once I've filled in the rest, the form doesn't submit (and I'm guessing this is because the ID field hasn't been filled in) Any help would be appreciated!!

Answer 1

id is null since you are setting it to $this->id which has not been set anywhere.
You can get the currently logged in user using Yii::$app->user->id. As such there is no need for the hidden field or the rules for id. You can just set the id manually using ActiveRecord::beforeSave():
public function beforeSave($insert = true) {
if ($insert)
$this->id = Yii::$app->user->id;
return parent::beforeSave($insert);
}