Select, which retrieves data remotely. It's available for large amounts of records that need to be filtered and loaded gradually in pages. The package offers an instant solution for javascript handling via Select2, or TomSelect.

Just as in a regular selectbox an array of values is passed, here a model providing the values is passed instead. The universal CallbackQueryModel can serve as the model, resolving everything via callbacks. The package also allows you to create your own custom implementation.

All communication with the backend goes through this model in the very same systematic way — there's no need to create any special AJAX endpoint or presenter action. Loading and filtering data is handled internally by the control through its own signal, just like any other signal in Nette components. Adding addSelectRemote() is therefore, from a usage point of view, exactly the same as adding a regular, non-remote selectbox — the only difference is that a model is passed instead of an array of values.

composer require tacoberu/nette-form-selectboxremote

After registering the extension, the addSelectRemote() and addMultiSelectRemote() shortcuts are available on the container:

extensions:
	- Taco\Nette\Forms\Controls\SelectBoxRemoteExtension

The package offers two ready-made handlers, both written in TypeScript and compiled into a JS module that's part of the package (vendor/tacoberu/nette-form-selectboxremote/assets/). The file is also available directly in the repository and needs to be exposed from your public folder (symlink or copy) and imported as an ES module. Filtering for a given field is available after enabling it with the data-class="filterable" attribute on the PHP side:

$form->addSelectRemote('category2', 'Category 2:', $model)
	->controlPrototype->data('class', 'filterable');

assets/remoteselect2.ts → assets/remoteselect2.js, the export initSelect2Impl(el, overrides?) is available.

	<link href="https://cdn.jsdelivr.net/npm/select2@4.0.10/dist/css/select2.min.css" rel="stylesheet" />
	<script src="https://code.jquery.com/jquery-3.7.1.js"></script>
	<script src="https://cdn.jsdelivr.net/npm/select2@4.0.10/dist/js/select2.min.js"></script>

	<script type="module">
		import { initSelect2Impl } from "/js/remoteselect2.js";
		document.querySelectorAll('select')
			.forEach(initSelect2Impl);
	</script>

jQuery is only needed as a dependency of Select2 itself (it's only available as a jQuery plugin) — the initSelect2Impl function itself does not depend on jQuery, it reads attributes through the native element.dataset. Pagination is available thanks to Select2's built-in ajax/pagination.more mechanism.

assets/TomSelectAdapter.ts → assets/TomSelectAdapter.js, the export initTomSelectImpl(el, overrides?) is available. Unlike Select2, TomSelect is available as a pure vanilla JS solution, with no dependency on jQuery.

	<link href="https://cdn.jsdelivr.net/npm/tom-select@2.6.1/dist/css/tom-select.css" rel="stylesheet" />
	<script src="https://cdn.jsdelivr.net/npm/tom-select@2.6.1/dist/js/tom-select.complete.min.js"></script>

	<script type="module">
		import { initTomSelectImpl } from "/js/TomSelectAdapter.js";
		document.querySelectorAll('select')
			.forEach(initTomSelectImpl);
	</script>

Pagination is available thanks to the official virtual_scroll plugin (included in tom-select.complete.min.js) and is switched on automatically for fields with data-type="remoteselect".

Both functions, initSelect2Impl and initTomSelectImpl, offer a second, optional parameter — an object that gets merged with the automatically derived settings. This makes any other feature of the given library available, for example reordering items in a multiselect (the drag_drop plugin for TomSelect) or the ability to add a new record (tags: true for Select2, create: true for TomSelect):

document.querySelectorAll('select').forEach((el) => {
	const overrides = el.multiple ? { plugins: ['drag_drop'], create: true } : {};
	initTomSelectImpl(el, overrides);
});

For TomSelect, plugins from the overrides are merged with virtual_scroll, which cannot be disabled — without it, pagination over AJAX would not be available.

The model can return arbitrary extra fields per item on top of id/label (e.g. flag, icon, description) — the library passes them through unchanged all the way to the JS layer. Rendering them (an icon, a flag, a description under the label, ...) is then up to your own template callback, enabled through the same overrides parameter:

// Select2: templateResult/templateSelection receive the whole item object.
initSelect2Impl(el, {
	templateResult: (data) => `${data.flag ?? ''} ${data.label}`,
});

// TomSelect: render.option/render.item receive the item object and an escape() helper.
initTomSelectImpl(el, {
	render: { option: (data, escape) => `<div>${escape(data.flag ?? '')} ${escape(data.label)}</div>` },
});

The example application demonstrates this on the countries field (flag + country name) and the accounts field (icon on the left, label and description stacked below it) — see DashboardPresenter::getCountrySelectModel() / getAccountSelectModel() and the corresponding <script type="module"> in select2.latte / tomselect.latte.

$form = new Nette\Forms\Form;

// CallbackQueryModel is buildin implementation of generic QueryModel.
$categorySelectQueryModel = new CallbackQueryModel(function($term, $page, $pageSize) use ($data) {
	$results = [];
	foreach ($data as $x) {
		if ($term && stripos($x->label, $term) === False) {
			continue;
		}
		$results[] = (object) [
			'id' => $x->id,
			'label' => $x->label,
		];
	}
	$total = count($results);
	$offset = ($page - 1) * $pageSize;
	return (object) [
		'total' => $total,
		'items' => array_slice($results, $offset, $pageSize),
	];
}, function($id) use ($data) {
	foreach ($data as $x) {
		if ($x->id === $id) {
			return (array) $x;
		}
	}
	return NULL;
});

// ...

$form->addSelectRemote('category', 'Category:', $categorySelectQueryModel);
$form->addMultiSelectRemote('tags', 'Tags:', $tagsSelectQueryModel);

examples/ contains a complete sample Nette application with two pages — /dashboard/select2 and /dashboard/tomselect — demonstrating the same PHP form handled by both JS libraries.

composer install
cp .env-example .env
php -S localhost:8001 examples/document_root/router.php

The application is then available at the address from .env (APP_URL).

npm run build:assets

The command compiles every *.ts file in assets/ (currently remoteselect2.ts and TomSelectAdapter.ts) into the matching .js file next to it.

npm install
npx playwright install chromium  # first time only

npm run test:e2e        # run the tests
npm run test:e2e:ui     # interactive UI

Two test suites are available: tests/e2e/remote-select.spec.ts for the Select2 variant and remote-select-tomselect.spec.ts for the same scenarios (loading, loading more, filtering) with TomSelect. The address of the tested application is set in .env via APP_URL, output is stored in temp/.