How to generate yii2 form with data coming from two models, but need to save changes to one of them

Question

Logged in users in my system can chose favorite CPV ID's. CPV's are main product of application, and they are stored in table cpv . Some columns in cpv table are : id , title , url .

Now I need to allow users to check which CPV's they like, and store/use that. I have formed user_cpv table that should store user and cpv id relation. Fields are id , user_id , cpv_id .

So first I would display all CPV's for the logged in user, but also, I would give him check boxes next to each of them so he can chose 3 favorite ones. Like this:

Before I continue I need to ask one subquestion: how can I display checkboxes without this label pulled from my model ( Cpv ID ) ?

To continue: so in my index action of my controller, I am pulling cpv data from Cpv model. But also I guess that I need to pull stored values from user_cpv table, because for each user there, there can be up to 3 cpv_id stored as his favorites. I guess that I need that information if I want to mark some of the Cpv ID as checked. So if user has cpv_id in user_cpv table, those ids are marked as checked in the whole list displayed in the table that I showed you.

The image above displays the index action result ( I do not use any widgets ). I want to allow user to check some of these checkboxes and save that into user_cpv table. This is some of the code in my index view:

<table class="table table-striped table-bordered my-favourites">
<?php $form = ActiveForm::begin(['action' => ['user-cpv/create']]); ?>
    <?php foreach ($values as $data): ?>
        <tr>
            <td><?= $data['cpvId'] ?></td>
            <td><?= $form->field($model, 'cpv_id')->checkbox() ?></td>
        </tr>
    <?php endforeach ?>
<?php ActiveForm::end(); ?>
</table>

Here, I am stuck. When I am displaying CPV's ( lets take just their ids like in picture ), how to mark as checked those that are stored in user_cpv relation table ? Here is some rough dirty pseudo code that I have in my mind :

actionIndex() {

    // pull data from cpv table
    $model = CPV::find();

    // pull data from user_cpv
    $relation = UserCpv::find();

    // somehow find those that match and maybe pass that info to view ?
}

Then in my view, how to set cpv_ids found in user_cpv as checked, if this is the checkbox render method ? :

<?= $form->field($model, 'cpv_id')->checkbox() ?>

And at last, if user check some other boxes, need to validate that he has chosen maximum of 3 boxes, and finally save that.

Can someone help me with this? Any help is appreciated, guidelines, example codes... Maybe my idea with user_cpv relation table is wrong ? Thank you

Answer 1

• For this first you need to define a relation in cpv model relationship with cpv-user model. In cpv model you will define relation (sample for relation model).

  public function getUsercpv(){ return $this->hasMany(UserCpv::className(), ['id' => 'cpv_id']); }

• now in controller you pull data from CPV model with relation

  // pull data from cpv table $model = CPV::find()->joinWith('usercpv');

• In view you can get user-cpv data using $data->usercpv, and can loop throug