Yii - Joins on tables are not working - php

Question

I want to get the data from two tables. I have used the below code to do so. I am new to Yii, if I am doing it the wrong way, please suggest the right way.
Here is the code of controller:
$dataProvider=new CActiveDataProvider('Users', array(
'criteria'=>array(
'with'=>'leave',
'together'=>true,
'condition'=>'leave.user_id=:user_id',
'params'=>array(':user_id'=>$this->loadModel(Yii::app()->user->getId())->user_id),
),
));
$this->render('admin',array(
'dataProvider'=>$dataProvider,
));
Here is the code of view:
$this->widget('zii.widgets.grid.CGridView', array(
'id'=>'users-grid',
'dataProvider'=>$dataProvider,
'columns'=>array(
array(
'header' => 'Leave Type',
'name'=>'leave_type',
'value'=>'$data->leave->leave_type',
),
'employee_code',
'username',
'password',
array(
'class'=>'CButtonColumn',
),
),
));
My Problem is:
I am joining two tables User and Leave. I want to get the data of users from Leave table as well as the users table. the above code shows me data from user table, when i try to show data from Leave table it throws me following error:
Trying to get property of non-object
UPDATE
Here is my user model relations:
return array(
'leaves' => array(self::HAS_MANY, 'Leaves', 'leave_id'),
'creator' => array(self::BELONGS_TO, 'Users', 'created_by'),
'updator' => array(self::BELONGS_TO, 'Users', 'modified_by'),
'leave' => array(self::HAS_MANY, 'Leaves', 'user_id'),
);
Here is my leave model relations:
return array(
'user' => array(self::BELONGS_TO, 'Users', 'user_id'),
'creator' => array(self::BELONGS_TO, 'Users', 'created_by'),
'updator' => array(self::BELONGS_TO, 'Users', 'modified_by'),
);

Answer 1

You can't display leave relation, because it's a HAS_MANY, I mean, in your $data->leave you have an array of Leave objects.
You should implement implode function, for example:
'value'=> "implode(', ', array_map(function($object) { return $object->leave_type; },
$data->leave))"
BTW, leave relation i think should be a HAS_ONE instead of HAS_MANY, and in this case, you don't need in an implode function in GridView

Answer 2

'value'=>'$data->leave->leave_type', // WRONG
$data->leave = array of objects and you could not access directly leave_type from it. That array was returned from your below relation:
'leave' => array(self::HAS_MANY, 'Leaves', 'user_id'),
I'm not sure the leave type which you want to access and relate it with user. But in this case, the solution is you can add more relation to just access first leave record of user
'singleLeave' => array(self::HAS_ONE, 'Leaves', 'user_id'), // add this line on Model User
And then you can access it properly
'value'=>'$data->singleLeave->leave_type',
Actually, in the first approach, the $data->leave should populate array of Leaves and from there, each Leave record should have to go into child views, and this is the point where you have to go detail