How to programmatically render a view pager?

Question

I'm trying to figure out how to render a view's pager programmatically. I'm renderering my view programmatically as follows:

$viewname = 'example_view';
$viewdisplay = 'block';

// get the view machine id
$view = Views::getView($viewname);
// set the display machine id
$view->setDisplay($viewdisplay);
$view->render();

$renderer = $view->rowPlugin;
foreach ($view->result as $index => $row) {
  $view->row_index = $index;
  $vars['content']['view_results'][$index] = $renderer->render($row);
}

So now I need to render the pager, but not having any luck. I've tried something like:

$pagerrenderer = $view->pager;
$vars['content']['view_pager'] = $pagerrenderer->render($view->pager);

but then end up with the following error:

Recoverable fatal error: Argument 1 passed to pager_query_add_page() must be of the type array, object given, called in /www/projectname/docroot/core/includes/pager.inc on line 246 and defined in pager_query_add_page() (line 311 of core/includes/pager.inc).

Can anyone point me in the right direction?

Answer 1

The object returned from $views->pager() is an object implementing ViewsPluginInterface and extending PagerPluginBase. If you look at the parameters PagerPluginBase::render() accepts, you will see they are:

$input: Any extra GET parameters that should be retained, such as exposed input.

If you look at Full::render(), you have an idea of how that parameter is used.

  $tags = array(
    0 => $this->options['tags']['first'],
    1 => $this->options['tags']['previous'],
    3 => $this->options['tags']['next'],
    4 => $this->options['tags']['last'],
  );
  return array(
    '#theme' => $this->themeFunctions(),
    '#tags' => $tags,
    '#element' => $this->options['id'],
    '#parameters' => $input,
    '#quantity' => $this->options['quantity'],
    '#route_name' => !empty($this->view->live_preview) ? '<current>' : '<none>',
  );

In any case, you don't pass to the method of that object the object itself.