Calculate average from kartik gridview(YII2) - yii2

Question

I am making a cost accounting application. And then in a case, I have success to sum data, but when I want get a average, I get an error. I have to try too much code in here, but nothing result.
How can I do to get average from my data here?
This is my view:
<?php
use yii\helpers\Html;
use yii\widgets\DetailView;
use kartik\grid\GridView;
use yii\data\ActiveDataProvider;
use backend\models\Penerimaan;
use yii\web\App;
/* #var $this yii\web\View */
/* #var $model backend\models\Triwulan */
$this->title = $model->rm_code;
$this->params['breadcrumbs'][] = ['label' => 'Triwulan', 'url' => ['index']];
$this->params['breadcrumbs'][] = $this->title;
?>
<div class="triwulan-view">
<h1><?= Html::encode($this->title) ?></h1>
<p>
<?= Html::a('Update', ['update', 'id' => $model->rm_code], ['class' => 'btn btn-primary']) ?>
<?= Html::a('Delete', ['delete', 'id' => $model->rm_code], [
'class' => 'btn btn-danger',
'data' => [
'confirm' => 'Are you sure you want to delete this item?',
'method' => 'post',
],
]) ?>
</p>
<?= DetailView::widget([
'model' => $model,
'attributes' => [
'rm_code',
'deskripsi_barang',
],
]) ?>
<?= GridView::widget([
'dataProvider'=>new yii\data\ActiveDataProvider([
'pagination'=>false,
'query'=>$model->getPenerimaans(),
]),
'columns'=>[
['class' => 'kartik\grid\SerialColumn'],
[
'attribute'=>'bulan',
'pageSummary' => 'Jumlah',
], [
'attribute' => 'price' ,
// 'pageSummary' => 20 - 20 - $model->idDhs->idMatakuliah->sks,
'pageSummary' =>(true),
'value' => function ($model) {
if($model)
return $model->price;
}
],
// ['class' => 'kartik\grid\ActionColumn'],
// 'product',
// 'qty'
],
'showPageSummary' => true,
])
?> Harga rata-rata barang adalah:
<?php
//$db= Yii::$app->db;
// $command=$db->createCommand('Select * from penerimaan where id=408');
// $penerimaan = $command->queryAll();
// foreach ($penerimaan as $penerimaans) {
// echo $penerimaans['price'];
// } echo "<br>";
// $users = Yii::$app->db->createCommand('SELECT * FROM penerimaan where rm_code=id')->queryAll();
//$connection= Yii::$app->db;
// $users= $connection->createCommand('SELECT * FROM penerimaan where rm_code=id')->execute();
// var_dump($users);
// $participantProvider = new ActiveDataProvider([
// 'query' => Penerimaan::find()->where('price',$model),
//]);
// $hasil = 14 /$participantProvider->getTotalCount();
// echo $hasil;echo "</br>";
?>
</div>
</div>

Answer 1

This was the already answered question and was correct answer, but I think you are not able to figure-out the solution.
Now add this code on your view page and try
<?php
use yii\helpers\Html;
use yii\widgets\DetailView;
use kartik\grid\GridView;
use yii\data\ActiveDataProvider;
use backend\models\Penerimaan;
use yii\web\App;
/* #var $this yii\web\View */
/* #var $model backend\models\Triwulan */
$this->title = $model->rm_code;
$this->params['breadcrumbs'][] = ['label' => 'Triwulan', 'url' => ['index']];
$this->params['breadcrumbs'][] = $this->title;
?>
<div class="triwulan-view">
<h1><?= Html::encode($this->title) ?></h1>
<p>
<?= Html::a('Update', ['update', 'id' => $model->rm_code], ['class' => 'btn btn-primary']) ?>
<?= Html::a('Delete', ['delete', 'id' => $model->rm_code], [
'class' => 'btn btn-danger',
'data' => [
'confirm' => 'Are you sure you want to delete this item?',
'method' => 'post',
],
]) ?>
</p>
<?= DetailView::widget([
'model' => $model,
'attributes' => [
'rm_code',
'deskripsi_barang',
],
]) ?>
<?php
$myAverage = 0;
$myTot =0;
$myCnt = 0;
$data = $dataProvider->getModels();
foreach ($data as $key => $value) {
$myTot += $value['price'];
$myCnt++;
}
if ($myCnt>0){
$myAverage = $myTot/$myCnt;
}
echo $myAverage; // your average displayed herre, you can place it wherever you want.
?>
<?= GridView::widget([
'dataProvider'=>new yii\data\ActiveDataProvider([
'pagination'=>false,
'query'=>$model->getPenerimaans(),
]),
'columns'=>[
['class' => 'kartik\grid\SerialColumn'],
[
'attribute'=>'bulan',
'pageSummary' => 'Jumlah',
],
[
'attribute' => 'price' ,
'pageSummary' =>(true),
'value' => function ($model) {
if($model)
return $model->price;
}
],
],
'showPageSummary' => true,
])
?>
</div>
</div>