Select2 in php forms?

Question

I have a simple quickform --

    $this->add('text','trial_number','Trial Number',TRUE);
    $this->add('date','Trial_Date',ts('Trial Date'),CRM_Core_SelectValues::date(NULL, 'Y M d',15,1) );
    $this->addEntityRef('judge',ts('Assigned Judge'));
    $this->add('advmultiselect','started_components','Started Components',$this->getOptions("regComponents"),FALSE);
    $this->add('advmultiselect','advanced_components','Advanced Components',$this->getOptions("regComponents"),FALSE);
    $this->add('advmultiselect','excellent_components','Excellent Components',$this->getOptions("regComponents"),FALSE);
    $this->add('checkbox','elite_offered','Elite Offered',FALSE);
    $this->add('advmultiselect','games_components','Games Components',$this->getOptions("gameComponents"),FALSE);  

However, the advmultiselect fields I would like to use select2 for multiple selections of the options. I have searched, and searched, yet cannot find any examples as to the format of the select2 add. The options are straight forward - all in a function called getOptions(). The advmultiselect works, but well, that's just ugly.

What is the format of the add('select2'.... and what attributes can I set?

Thanks Norm

Answer 1

It should work using the following format

$this->add('select', [YOUR CODE HERE] array('multiple' => TRUE, 'class' => 'crm-select2'));

https://docs.civicrm.org/dev/en/latest/framework/quickform/entityref/
https://select2.org/