Adding a new field depending of other field

Hello,

i need to add a writable field only when the user select "yes", otherwise that field need to be hidden.

How can i do that?

I tried JS, selecting the field and showing the other field, but didnt work.

I tried with CodeIgniter code, calling a function in a CallbackAfterInsert, but nothing...

$crud->callbackAfterInsert(function ($stateParameters) {
		
			if($stateParameters->data['is_group'] == 1){
			    $this->grupo_empresas($stateParameters->data['client_id']);
			    return $stateParameters;			
		
			}else{
			    return $stateParameters;				
			}
			
		});

Adding a new field depending of other field

AndresSEGC