How to create a textfield with autocomplete function for the view? My Drupal 8 website is multilingual, and on one of the views I present a list of nodes (titles). On top of the page I need to implement a textfield with autocomplete function, where the user can start typing in the language, and then by choosing one the content on the page will be presented in chosen language. 

I have started by creating a custom block: 

public function build(){

$block = array(
  '#type' =&gt; 'textfield',
  '#title' =&gt; t('Choose language'),
  '#autocomplete_path' =&gt; '?????',
  '#cache' =&gt; array(
    'max-age' =&gt; 0,
  ),
);
return $block;


}

What should I write in '#autocomplete_path' => '?????' as the list of languages is not taxonomies. It is coming from Languages module. Could you please help me?
I think no need to create block of view programmatically, You can do it with Views Autocomplete Filters module and views Module:
Try the following steps how to create view with language filter, using autocomplete:


Install Views Autocomplete Filters Module.
Create View with Fields Display add the language field The language of the content or translation.
 and your additional fields:

Add Combine fields filter 



configure it like the following:




the result will be like: