Codeigniter, using set_checkbox in a controller - codeigniter

Question

I've got a loop that generates checkboxes, I have it working within the view, but I would like to move it into the controller and then pass the resulting string to the view. The problem is set_checkbox() doesn't seem to remember the values when it's placed in a controller. It does however seem to set the default value.
Edit: This is only an issue when validation fails and I want checkboxes to retain the users selections. Otherwise code is working as expected. I also have a validation rule set.
$languages_by_name = $this->event_model->get_spoken_languages_by_name();
// Generate array from model data for form_dropdown()
$i = 1;
$list_languages = '';
foreach ($languages_by_name as $row) {
$i == 1 ? $first = TRUE : $first = FALSE; // Check if this is the first radio and precheck it.
$list_languages .= '<label>' . form_checkbox('spokenLanguages[]', $row->event_spoken_id, set_checkbox('spokenLanguages', $row->event_spoken_id, $first)) . ' ' . $row->name . '</label> ';
$i++;
}
// Pass $list_languages to view
$this->data['list_languages'] = $list_languages;

Answer 1

Here's working code for the controller. There might be a more elegant way to do this.
// Generate array from model data for form_dropdown()
$i = 1;
$list_languages = '';
foreach ($languages_by_name as $row) {
// Check if there is post data
if(!$this->input->post('spokenLanguages')) {
// Set first element to checked
$i == 1 ? $selection = TRUE : $selection = FALSE; // Check if this is the first radio and precheck it.
} else {
// Check if this input is checked
if(in_array($row->event_spoken_id, $this->input->post('spokenLanguages'))) {
$selection = TRUE;
} else {
$selection = FALSE;
}
}
$list_languages .= '<label>' . form_checkbox('spokenLanguages[]', $row->event_spoken_id, set_checkbox('spokenLanguages', $row->event_spoken_id, $selection)) . ' ' . $row->name . '</label> ';
$i++;
}
// Pass $list_languages to view
$this->data['list_languages'] = $list_languages;