When we need to to call another controller function,we can simply use the below code

Yii::$app->runAction('publish/commit',[
                    'r' => 'ws'
]);

write it in Controller A index method and you can get the value of $r  in Controller Publish commit method.

Answer

In a layout you can access the current controller via $this->context, and so the current action id by $this->context->action->id

For reference http://stackoverflow.com/questions/28769719/yii2-get-current-action-id-in-main-php

Pagination represents information relevant to pagination of data items.

When data needs to be rendered in multiple pages, Pagination can be used to represent information such as total item count, page size, current page, etc. These information can be passed to pagers to render pagination buttons or links.

The following example shows how to create a pagination object and feed it to a pager.

Controller action:

public function actionSearch($q = '') {
        $this->layout = 'site_main';

        $q = trim($q);

        $sql = "SELECT * FROM
(select p.product_id as 'sid',p.name_en,p.name_ar,p.description_en,description_ar,p.image, 'product' as 'type', 'none' as 'category_type'
from tbl_products p
union
select sl.service_location_id as 'sid' ,sl.name_en,sl.name_ar,sl.description_en,sl.description_ar,sl.image,'servicelocation' as 'type' ,'none' as 'category_type'
from tbl_service_locations sl
)
as search
WHERE search.name_en LIKE '$q%' or search.name_ar LIKE '$q%' or search.description_en LIKE '$q%' or search.description_ar LIKE '$q%'  
";
        $query = Yii::$app->db->createCommand($sql)->queryAll();

        $count = sizeof($query);

        //echo $count;

        $dataProvider = new SqlDataProvider([
            'sql' => $sql,
            'totalCount' => $count,
            'pagination' => [
                'pageSize' => 10,
            ],
        ]);

        //$models = $dataProvider->query;

        return $this->render('search', [
                    'q' => $q,
                    'result' => $dataProvider->getModels(),
                    'dataProvider' => $dataProvider,
                    'count' => $count,
        ]);
    }

View :

foreach ($result as $row) {

 // display $model here

}

// display pagination

echo yiiwidgetsLinkPager::widget([
    'pagination' => $dataProvider->pagination,
 ]);

For reference please visit

http://www.yiiframework.com/doc-2.0/yii-data-pagination.html

leftJoin()

$query = new Query;
$query    ->select(['tbl_user.username AS name', 'tbl_category.type as Category'])  
        ->from('tbl_user')
        ->leftJoin('tbl_category', 'tbl_category.createdby = tbl_user.userid')
        ->limit(2);
       
$command = $query->createCommand();
$data = $command->queryAll();

innerJoinWith()

$model = User::find()
    ->innerJoinWith('comments', false)
    ->all();
// equivalent to the above
$model = User::find()
    ->joinWith('comments', false, 'INNER JOIN')
    ->all();

SYNTAX:

$query = new Query;
$query    ->select(['SELECT COLUMNS'])  
        ->from('TABLE_NAME_1')
        ->join(    'JOIN_TYPE',
                'TABLE_NAME_2',
                'TABLE_NAME_2.COLUMN =TABLE_NAME_1.COLUMN'
            );
$command = $query->createCommand();
$data = $command->queryAll();               

Sample 1:

$query = new Query;
$query    ->select([
        'tbl_user.username AS name',
        'tbl_category.categoryname as  Category',
        'tbl_document.documentname']
        ) 
    ->from('tbl_user')
    ->join('LEFT OUTER JOIN', 'tbl_category',
                'tbl_category.createdby =tbl_user.userid')        
    ->join('LEFT OUTER JOIN', 'tbl_document',
                'tbl_category.cid =tbl_document.did')
    ->LIMIT(5)    ;
       
$command = $query->createCommand();
$data = $command->queryAll();   

joinWith()

Sample 1:

$model = User::find()
    ->joinWith('comments')
    ->all();

Sample 2:

$model = User::find()
    ->joinWith('comments')
    ->orderBy('tbl_comments_id.id, tbl_user.id')
    ->all();

Relation Model

$model = User::find()
        ->with('comments')
        ->all();
    foreach ($model as $user) {
        // get data from relation model
        $comments = $user->comments;
        ......
        foreach($comments as $comment){
            ........
        }
    }

<?php
use yiiwidgetsPjax;
?>


Add above line in the beginning of your view. 


<?php Pjax::begin(); ?>

<?= GridView::widget([
    'dataProvider' => $dataProvider,
    'filterModel' => $searchModel,
    'columns' => [
        ['class' => 'yiigridSerialColumn'],

        'id',
        'branch:ntext',
        'version:ntext',
        'release_date:ntext',

        [
            'class' => 'yiigridActionColumn',
            'template' => '{view}',
        ],
    ],
]); ?>

<?php Pjax::end(); ?>

First, let's enable Yii2's pretty URLs with mod_rewrite. On the Yii home page, if you click on the About menu option, the URL will be something like http://localhost/hello/web/index.php?r=site%2Fabout. We'd like to change that to http://localhost/hello/web/site/about.

The config subdirectory includes environment configurations for your web and console applications as well as the future database settings. Edit /config/web.php to add urlManagement to the current web application. Add the following urlManager section within the components array:

Then, create an .htaccess file within /web where the primary index.php file exists:

Make sure mod_rewrite is running locally on MAMP; if not, check out this Stack Overflow guide.

In your browser, visit this URL: http://localhost/hello/web/site/about. You should see the Yii application About page and clicking on other menu options should bring up pretty URLs.