How to allow system templates for InputfieldSelector for a field?

[artfulrobot]

I have a selector field and I need it to be able to select User templates, but User is hidden because it's a system template.

I thought I could make this change with a hook, but I have not been successful. To try, I made a new module (single, auto load) and in its init() method I added code like this:

class MyCustomModule extends Process implements Module {
  ...
  public function init() {
    $this->wire->addHookBefore('Inputfield::getConfigInputfields', function (HookEvent $event) {
      $this->wire->log('getConfigInputfields Fired', ['name' => 'testHooks']);
    });
    $this->wire->addHookBefore('InputfieldSelector::init', function (HookEvent $event) {
      $this->wire->log('InputfieldSelector::init', ['name' => 'testHooks']);
    });
  }
  ...
}

I thought that if I hooked into when an InputfieldSelector got instantiated, I could check whether it was the field I wanted to target and if so, make the setting change. But none of these hooks fired when I edited the page.

Currently, I have achieved this through changing InputfieldSelector.module's __construct()  method, but I wanted to do it with a hook so it has more of a chance of not getting removed on upgrade!

Any help appreciated 🙂

[BitPoet]

Did you set the autoload property in your module?

I've assembled a snippet for site/ready.php that should add a checkbox to InputfieldSelector to allow system templates since the setting itself is already part of the inputfield code. Untested though since I'm in the middle of a big cleanup of my dev environment.

wire()->addHookAfter('InputfieldSelector::getConfigInputfields', function (HookEvent $event) {
  
  $fields = $event->return;
  $inputfield = $event->object;
  
  $f = $event->modules->get('InputfieldCheckbox');
  $f->attr('id+name', 'allowSystemTemplates');
  $f->label = $event->_('Allow system templates');
  $f->setAttribute('checked', $inputfield->getSetting('allowSystemTemplates') ? 'checked' : '');
  $fields->append($f);
  
  $event->return = $fields;
  
});