create an expandable grid view in Yii2 - yii2

Question

I am trying to create an expandable grid view in Yii2 but I have some problems.
I get this warning:
PHP Warning – yii\base\ErrorException
reset() expects parameter 1 to be array, null given
in C:\xampp\htdocs\advanced\vendor\yiisoft\yii2\grid\DataColumn.php at line 129
$provider = $this->grid->dataProvider;
if ($this->label === null) {
if ($provider instanceof ActiveDataProvider && $provider->query instanceof ActiveQueryInterface) {
/* #var $model Model */
$model = new $provider->query->modelClass;
$label = $model->getAttributeLabel($this->attribute);
} else {
$models = $provider->getModels();
129 if (($model = reset($models)) instanceof Model) {
/* #var $model Model */
$label = $model->getAttributeLabel($this->attribute);
} else {
$label = Inflector::camel2words($this->attribute);
}
}
} else {
$label = $this->label;
}
This is my search model code:
<?php
namespace app\models;
use Yii;
use yii\data\ActiveDataProvider;
use yii\base\Model;
use app\models\Articles;
/**
*
*/
class ArticlesSearch extends Model
{
/* your calculated attribute */
public $article_num;
public $title;
public $jour_id;
/* setup rules */
public function rules() {
return [
/* your other rules */
[['title'], 'safe']
];
}
public function search($params) {
$query = Articles::find()->select('*')
->where(['`journal_id`'=>$this->jour_id]);
$dataProvider = new ActiveDataProvider([
'query' => $query,
]);
if (!($this->load($params) && $this->validate())) {
return $dataProvider;
}
$query->orderBy('`articles`.`publication_date` ASC ');
$query->andWhere(['LIKE','title',$this->title]);
// $query->orFilterWhere(['like', '`publishers`.`name`', $this->name]);
return $dataProvider;
}
public function getCount()
{
}
public function getModels()
{
}
}
I added two last methods to my class to bypass the following error:
Calling unknown method: app\models\ArticlesSearch::getCount()
Calling unknown method: app\models\ArticlesSearch::getModels()
I don't know why I need this two methods in my class. I have written two other search models and I didn't put these methods there and they work fine!!!
Controller code:
$dataProvider=new ArticlesSearch();
$dataProvider->jour_id=$param['journalID'];
$searchModel= $dataProvider->search(Yii::$app->request->queryParams);
return $this->render('index', [ 'searchModel' => $searchModel,
'dataProvider' => $dataProvider]);
View code:
<?= GridView::widget([
'dataProvider' => $dataProvider,
'filterModel' =>$searchModel,
'columns' => [
[
'class'=>'kartik\grid\SerialColumn',
'contentOptions'=>['class'=>'kartik-sheet-style'],
//'width'=>'36px',
'header'=>'',
'headerOptions'=>['class'=>'kartik-sheet-style']
],
[
'class'=>'kartik\grid\CheckboxColumn',
'headerOptions'=>['class'=>'kartik-sheet-style'],
],
[
'class'=>'kartik\grid\ExpandRowColumn',
//'width'=>'50px',
'value'=>function ($model, $key, $index, $column) {
return GridView::ROW_COLLAPSED;
},
'detail'=>function ($model, $key, $index, $column) {
// return Yii::$app->controller->renderPartial('_expand-row-details', ['model'=>$articles]);
},
'headerOptions'=>['class'=>'kartik-sheet-style']
//'disabled'=>true,
//'detailUrl'=>Url::to(['/site/test-expand'])
],
[
'attribute'=>'Title',
//'value' => $model->title,
// 'width'=>'410px',
],
],
]);
?>
Any help would be much appreciated.

Answer 1

Try this amended code and see if it works. I've added some comments to explain what is going on.
<?php
namespace app\models;
use Yii;
use yii\data\ActiveDataProvider;
use app\models\Articles;
/**
** firstly, your search model needs to extend your original class, that was you have access to all the original attributes of your model, without having to declare them again.
**/
class ArticlesSearch extends Articles
{
//If your original model already has these properties, you don't need to declare them again.
public $article_num;
public $title;
public $jour_id;
/* Here you should declare rules for ALL the attributes that you want to use in search */
public function rules() {
return [
/* your other rules */
[['title', 'jour_id', 'article_num'], 'safe']
];
}
public function search($params) {
//Start by defining your basic search function
$query = Articles::find();
//Add in the dataProvider
$dataProvider = new ActiveDataProvider([
'query' => $query,
]);
//Start building the query that will be used to retrieve results
$query->where(['jour_id' => $this->jour_id]);
//Try to load the $params and validate them. If this fails, just return the dataProvider and do nothing else
if (!($this->load($params) && $this->validate())) {
return $dataProvider;
}
//If we're still in the method, carry on building the query
$query->orderBy('`articles`.`publication_date` ASC ');
//andFilterWhere() is better because it ignores empty values
$query->andFilterWhere(['LIKE','title',$this->title]);
return $dataProvider;
}
//Finally, remove the two extras functions you put in. If everything is working, you shouldn't need them.
}
Next, in your controller, use this code;
//Here you are telling Yii what model you want to use for searching, and for generating the form for the grid search.
$searchModel = new ArticlesSearch();
//I'm not sure where this $param is coming from.
$dataProvider->jour_id=$param['journalID'];
//Now you are actually setting up the dataProvider for the grid view. Notice that your $searchModel->search() method always returns a dataProvider, so this is the correct way to do it. Yii::$app->request->queryParams is loading the parameters that the search method will use for it's parameters.
$dataProvider = $searchModel->search(Yii::$app->request->queryParams);
return $this->render('index', ['searchModel' => $searchModel, 'dataProvider' => $dataProvider]);
Now you should be able to use the grid widget as normal, use the dataProvider and searchModel for your dataProvider and filterModel respectively, but don't mix them up!