Using the jamselect widget with min and max values

How-tos

Form validation, Widgets

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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](http://www.yiiframework.com/extension/jamselect/ "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 <?php
 
$this->widget(
'application.extensions.asmselect.JAMSelect',
array('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)
 
------------------------------------ ```php 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.
 
```php 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. ```php public function getKeywords($delimited) {     $keys = explode(',',$delimited);     return $keys; } ``` #### Rules
 
----- And now for the rules (in the model file)
 
```php 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
 
----------------------- ```php 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