// First render the main content, because it might provide a title.
$content =
$this->renderer->
renderRoot($main_content);
// Attach the library necessary for using the OpenDialogCommand and set the
// attachments for this Ajax response.
$main_content['#attached'
]['library'
][] = 'core/drupal.dialog.ajax';
$response->
setAttachments($main_content['#attached'
]);
// Determine the title: use the title provided by the main content if any,
// otherwise get it from the routing information.
$title =
$main_content['#title'
] ??
$this->titleResolver->
getTitle($request,
$route_match->
getRouteObject());
// Determine the dialog options and the target for the OpenDialogCommand.
$options =
$request->request->
all('dialogOptions'
);
$target =
$this->
determineTargetSelector($options,
$route_match);
$response->
addCommand(new OpenDialogCommand($target,
$title,
$content,
$options));
return $response;
} /**
* Determine the target selector for the OpenDialogCommand.
*
* @param array &$options
* The 'target' option, if set, is used, and then removed from $options.
* @param \Drupal\Core\Routing\RouteMatchInterface $route_match
* When no 'target' option is set in $options, $route_match is used instead
* to determine the target.
*
* @return string
* The target selector.
*/