The problem ¶

I needed to have users select from a list of keywords, in this example they must select at least two keywords but they cannot select more than six.

The keywords will be stored in a text field in a comma delimited format. The keywords will be created by the site administrator.

In a very timely fashion the jamselect widget showed up, thanks volkmar!

The widget does not provide min/max filtering so I will implement a custom rule.

First put the widget in a form ¶

This is my implementation.

<?php	

$this->widget(
    'application.extensions.asmselect.JAMSelect',
    array(
        'selected'=>$this->getKeywords($model->keywords),
		'data'=>CHtml::listData(Keywords::model()->findAll(),'word', 'word'),
                'htmlOptions'=>array(
            'title'=>'Select up to six keywords',
            'name'=>'keywordArray'
        ),
        'animate'=>true
    ));

?>

A few things to notice ¶

The widget is located in /protected/extensions not /protected/extensions/widgets, I only point this out for people who aren't sure where to put things. You have quite a bit of flexibility on where you locate widgets and components. It doesn't makes sense to me to create another folder in extensions but perhaps on a very large project it would.

The dropdown list data is being pulled from a table that has only two fields, 'id' and 'word', since I want to select the word from the list and store exactly the same value in the database I need a key=>value array that looks like 'word'=>'word'.

The $_POST data will contain an array of selected values, this will be in $_POST['keywordArray']

Lets look at the controller (create) ¶

public function actionCreate()
	{
		$model=new EventAbstract;
		
		$this->layout = '//layouts/column1';

		// Uncomment the following line if AJAX validation is needed
		// $this->performAjaxValidation($model);

		if(isset($_POST['EventAbstract']))
		{
			$model->attributes=$_POST['EventAbstract'];

     // I better do a check in case no keywords were selected
    $keywordArray = (!isset($_POST['keywordArray']) ? array() : $_POST['keywordArray']); 

    // now I either have an array of keywords or an empty array
    // send the array to a function to format the keywords in a 
    // comma delimited format
    $this->setKeywords($model,'keywords',$keywordArray);

    // it's all done but not yet validated
			if($model->save())
				$this->redirect(array('view','id'=>$model->id));
		}

		$this->render('create',array(
			'model'=>$model,
		));
	}

Here is the function that formats the keywords ¶

Remember the keywords are suppled by the admin so I am not doing any checking here for capitals or illegal characters.

public function setKeywords($model,$field,$keys)
	{
		$model->$field = (empty($keys) ? null : implode(',',$keys));
	}

Update record ¶

And when we perform an update on the record we have to turn our comma delimited field back into an array, so similarly.

public function getKeywords($delimited)
	{
		$keys = explode(',',$delimited);
		return $keys;
	}

Rules ¶

And now for the rules (in the model file)

public function rules()
	{
		// NOTE: you should only define rules for those attributes that
		// will receive user inputs.
return array(
// other rules are here
			    array('keywords','keywordCount','skipOnError'=>true,'maxKeys'=>6,'minKeys'=>2),
// keywords is the field in the table currently holding the submitted value
// $model->keywords
// keywordCount is the function (in the model) that will do the validation
//
//skipOnError, maxKeys and minKeys are all parameters that will be sent to the validation function

// other rules

);
	
	}

The validation function ¶

public function keywordCount($attribute,$params)
{
	 $keys = explode(',',$this->$attribute);
// check if there are keywords exist
	if(!$this->$attribute)
	{
	    $this->addError($attribute,'<strong>If you need to add a keyword please contact the administrator</strong>');
	} 
// check if there are enough keywords
	if(count($keys) < $params['minKeys'])
	{
	    $this->addError($attribute,'Please choose at least '.$params['minKeys'].($params['minKeys'] > 1 ? ' keywords' :' keyword'));
	} 
// check if there are too many keywords
	if(count($keys) > $params['maxKeys'])
	{
	    $this->addError($attribute,'You have chosen too many keywords max = '.$params['maxKeys']);
	}	 
}
	

Now the user can select between 2 and 6 keywords.

doodle