Yii2 dropdown multiple selected

MultiSelect Widget for Yii2

It supports searching, remote data sets, and infinite scrolling of results.

https://github.com/kartik-v/yii2-widget-select2

Kartik Multiselect widget

in _form.php

use kartik\select2\Select2;



<?php
    echo Select2::widget([
        'model' => $model,
        'name' => 'certificates',
        'attribute' => 'certificates',
        'data' => ArrayHelper::map(Mulcertificates::find()->orderBy('description')->all(),'id','description'),  //['1'=>'1','2'=>2],
        'options' => [
            'placeholder' => 'Select certificates ...',
            'multiple' => true
    ],
    ]);
    ?>


Controller.php

public function actionCreate()
    {
        $model = new Mulselect();

        if ($model->load(Yii::$app->request->post())) {
         
            $model->certificates = implode(",",$model->certificates);
            
            $model->save();
            return $this->redirect(['view', 'id' => $model->id]);
         
        } else {
            return $this->render('create', [
                'model' => $model,
            ]);
        }
    }


 public function actionUpdate($id)
    {
        $model = $this->findModel($id);

        if ($model->load(Yii::$app->request->post()) && $model->save()) {
            return $this->redirect(['view', 'id' => $model->id]);
        } else {
            $model->certificates= explode(',', $model->certificates);
            return $this->render('update', [
                'model' => $model,
            ]);
        }
    }


Links

Select2 Widget 

2amigos/yii2-multi-select-widget