dependent dropdown yii2. How to do? - yii2

Question

can I create a dependent dropdown in yii2?
I have two tables:
'id','name_country"
'id','name_city','country_id'
and have two methods in my model:
public function getCountryList()
{
$models = NetCountry::find()->asArray()->all();
return ArrayHelper::map($models, 'id', 'country_name');
}
and
public function getCityList($parent_id) {
$models = \common\models\City::find()->where(['parent_id' => $country_id])->asArray()->all();
return ArrayHelper::map($models, 'id', 'name_city','country_id');
}
I have the first field:
<?= $form->field($model, 'country')->dropDownList($model->countryList),['id'=>'parent_id'];
and the second
<?= $form->field($model, 'city')->dropDownList($model->cityList);
I need to 'transmit' parent_id to controller and return city_list by AJAX (with JSON).
How can I do this? I saw an example in Yii1, but what about Yii2?

Answer 1

use the krajee extension for dependent drop down
Details is here Krejee dependent dropdown for yii2
or follow following instructions:
Install the extension via composer:
$ php composer.phar require kartik-v/dependent-dropdown "dev-master"
In your view :
use kartik\widgets\DepDrop;
// Normal parent select
echo $form->field($model, 'cat')->dropDownList($catList, ['id' => 'cat-id']);
// Dependent Dropdown
echo $form->field($model, 'subcat')->widget(DepDrop::classname(), [
'options' => ['id' => 'subcat-id'],
'pluginOptions' => [
'depends' => ['cat-id'],
'placeholder' => 'Select...',
'url' => Url::to(['/site/subcat'])
]
]);
// THE CONTROLLER
public function actionSubcat() {
$out = [];
if (isset($_POST['depdrop_parents'])) {
$parents = $_POST['depdrop_parents'];
if ($parents != null) {
$cat_id = $parents[0];
$out = self::getSubCatList($cat_id);
// the getSubCatList function will query the database based on the
// cat_id and return an array like below:
// [
// ['id'=>'<sub-cat-id-1>', 'name'=>'<sub-cat-name1>'],
// ['id'=>'<sub-cat_id_2>', 'name'=>'<sub-cat-name2>']
// ]
echo Json::encode(['output'=>$out, 'selected'=>'']);
return;
}
}
echo Json::encode(['output'=>'', 'selected'=>'']);
}

Answer 2

creating dependent dropdown in yii2 without using any third party libraries is
quite as simple as yii1. you have to try following code written below as per your requirements.
use gii to create models,views, controller for respective tables.
suppose there r two table like country, city as u written.
then write the following code into views file for one controller(like country):
<?php
use yii\helpers\ArrayHelper;
use yii\widgets\ActiveForm;
?>
<div>
<?php
$dataCountry=ArrayHelper::map(\app\models\Country::find()->
asArray()->all(),'id', 'name');
$form = ActiveForm::begin();
echo $form->field($model, 'id')->dropDownList($dataCountry,
['prompt'=>'-Choose a Name-',
'class'=>'adjust',
'onchange'=>'
$.post("'.Yii::$app->urlManager->createUrl('city/lists?id=').
'"+$(this).val(),function( data )
{
$( "select#city" ).html( data );
});
']);
$dataPost=ArrayHelper::map(\app\models\City::find()->
asArray()->all(), 'id', 'city');
echo $form->field($model, 'id')
->dropDownList(
$dataPost,
['id'=>'city',
'class'=>'adjust'
]
);
ActiveForm::end();
?>
</div>
and after this in another controller for city write following code as:
<?php
namespace app\controllers;
class CityController extends \yii\web\Controller
{
public function actionLists($id)
{
//echo "<pre>";print_r($id);die;
$countPosts = \app\models\City::find()
->where(['country_id' => $id])
->count();
$posts = \app\models\City::find()
->where(['country_id' => $id])
->orderBy('id DESC')
->all();
if($countPosts>0){
foreach($posts as $post){
echo "<option value='".$post->id."'>".$post->city."</option>";
}
}
else{
echo "<option>-</option>";
}
}
}
then run into url it works!
edit: fixed url construction. http requests will now work.

Answer 3

You can do it without any widget manually:
make your activeform as follows:
<?= $form->field($model, 'nameofyourmodel')->dropDownList(
ArrayHelper::map(\app\models\nameofyourmodel::find()->all(), 'id', 'name'),
[
'prompt'=>'smth',
'onchange' => '
$.post(
"' . Url::toRoute('getoperations') . '",
{id: $(this).val()},
function(res){
$("#requester").html(res);
}
);
',
]
); ?>
and here the second form which receives the id from the first model:
<?= $form->field($model,'nameofyourmodel')->dropDownList(
[],
[
'prompt' => 'smth',
'id' => 'requester'
]
); ?>
and the last action is to make a functionality in controller to match 2 ids and send them to your model:
public function actionGetoperations()
{
if ($id = Yii::$app->request->post('id')) {
$operationPosts = \app\models\firstmodel::find()
->where(['id' => $id])
->count();
if ($operationPosts > 0) {
$operations = \app\models\secondmodel::find()
->where(['firstmodelid' => $id])
->all();
foreach ($operations as $operation)
echo "<option value='" . $operation->firstmodelid. "'>" . $operation->name . "</option>";
} else
echo "<option>-</option>";
}
}

Answer 4

The above code is not working properly. There is an error in the line
$.post("'.Yii::$app->urlManager->createUrl('city/lists&id=').'"+$(this).val(),function( data )
console shows the error :
Not Found (#404): Unable to resolve the request: subcategory/lists&id=54
is there any solution for this
my controller looks like below
public function actionLists($id)
{
$posts = SubCategory::find()
->where(['category_id' => $id])
->orderBy('id DESC')
->all();
if($posts){
foreach($posts as $post){
echo "<option value='".$post->id."'>".$post->name."</option>";
}
}
else{
echo "<option>-</option>";
}
}
when i remove the id from the url and hard coded it in to controller it works properly.
I have find a solution for this
please change your view as follows
<?= $form->field($model, 'category_id')->dropDownList($data,['prompt'=>'-Choose a Category-',
'onchange'=>'
$.get( "'.Url::toRoute('product/catlists').'", { id: $(this).val() } )
.done(function( data )
{
$( "select#product-sub_categoryid" ).html( data );
});
']); ?>
and controller like this
public function actionCatlists($id)
{
$mymodel = new Product ();
$size = $mymodel->modelGetCategory ( 'product_sub_category',$id );
if($size){
echo '<option value="">Choose Sub category</option>';
foreach($size as $post){
echo "<option value='".$post['id']."'>".$post['name']."</option>";
}
}
else{
echo '<option value="0">Not Specified</option>';
}
}
don't forget to include this on your view
use yii\helpers\Url;