Yii2-使用activerecord在gridview中显示关系数据的数量

Question

I have two tables Agencies and Agents, I want to show the number of agents each agency has using a count query ("agents" table has a column called 'agency_id'). there is an old post here on stackoverflow but it's not completely answered.

Here's what I tried so far:

In Agencies Model (to get the agent count in agencies gridview):

 */
public function getAgents()
{
    return $this->hasMany(Professionnels::className(), ['agency_id' => 'id']);

}

In Agents Model (to get the agency name in agents gridview):

public function getAgencies()
{
    return $this->hasOne(Agencies::className(), ['id' => 'agency_id']);
}

In Agencies view that shows the gridview:

'columns' => [
        ....,
         ['label' => 'Agents Number','attribute' => 'count(agents.id'),]

And in the AgenciesSearch:

$query = Agencies::find()->with('agents');

Answer 1

You can call the count() function on your relationship in the value attribute of your column:

'columns' => [
....,
  [
    'label' => 'Agents Number',
    'attribute' => 'agents',
    'value' => function ($model) { return $model->getAgents()->count();}
  ]

Another option would be to create a new method to get the Agents count in your Agency model:

public function getAgentsCount()
{
    return $this->getAgents()->count();
}

And call refer to it in your column:

'columns' => [
    ....,
      [
        'label' => 'Agents Number',
        'attribute' => 'agentsCount',
      ]