searchable_dropdown_pro

A highly flexible, production-ready searchable dropdown for Flutter with zero forced dependencies beyond the Flutter SDK itself.

Features

✅ Bring your own TextField — or use the sensible built-in default.
✅ Bring your own validator — standard Flutter form-field API.
✅ Toggle search on/off — isSearchable: false for a plain dropdown.
✅ Custom filter logic — override the default substring match.
✅ Custom item tiles — full control over each row.
✅ Composited overlay — stays pinned inside SingleChildScrollView.
✅ Async / lazy items — pass a new items list and the overlay refreshes.
✅ Programmatic control — open, close, clear, or pre-fill via SearchableDropdownController.
✅ Full theming — SearchableDropdownDecoration covers every visual detail.
✅ Null-safe — written for Dart 3 with sound null safety.

Getting started

Add the dependency to your pubspec.yaml:

dependencies:
  searchable_dropdown_pro: ^1.0.0

Then run:

flutter pub get

Usage

Minimal

import 'package:searchable_dropdown_pro/searchable_dropdown_pro.dart';

SearchableDropdownPro<String>(
  items: ['Apple', 'Banana', 'Cherry'],
  displayString: (item) => item,
  onSelected: (item) => print('Selected: $item'),
  hintText: 'Pick a fruit',
)

With a model class

class Country {
  final String name;
  final String flag;
  const Country(this.name, this.flag);
}

SearchableDropdownPro<Country>(
  items: countries,
  displayString: (c) => c.name,
  onSelected: (c) => _onCountrySelected(c),
  hintText: 'Select country',
)

Pass isSearchable: false and the list is shown as-is without a search input — identical behaviour to a plain DropdownButton but with a composited overlay and full theming.

SearchableDropdownPro<String>(
  isSearchable: false,
  items: ['Small', 'Medium', 'Large'],
  displayString: (s) => s,
  onSelected: (_) {},
  hintText: 'Select size',
)

Bring your own TextField

Supply fieldBuilder to render any widget as the trigger. The builder receives the managed TextEditingController, FocusNode, and a pre-built suffixIcon so you can embed your own design-system field:

SearchableDropdownPro<String>(
  items: items,
  displayString: (e) => e,
  onSelected: (_) {},
  hintText: 'Search…',
  fieldBuilder: (context, controller, focusNode, suffixIcon) {
    return MyDesignSystemTextField(
      controller: controller,
      focusNode: focusNode,
      suffixIcon: suffixIcon,
      hintText: 'Search…',
    );
  },
)

Bring your own validator

SearchableDropdownPro<String>(
  items: items,
  displayString: (e) => e,
  onSelected: (_) {},
  hintText: 'Required field',
  validator: (value) {
    if (value == null || value.isEmpty) return 'Please select an option';
    return null;
  },
  autovalidateMode: AutovalidateMode.onUserInteraction,
)

Custom item tiles

SearchableDropdownPro<Country>(
  items: countries,
  displayString: (c) => c.name,
  onSelected: (_) {},
  hintText: 'Country',
  itemBuilder: (context, country, isSelected, onTap) {
    return ListTile(
      leading: Text(country.flag, style: const TextStyle(fontSize: 24)),
      title: Text(country.name),
      selected: isSelected,
      onTap: onTap,
    );
  },
)

Custom filter

SearchableDropdownPro<String>(
  items: items,
  displayString: (e) => e,
  onSelected: (_) {},
  hintText: 'Starts-with search',
  filterBuilder: (items, query) =>
      items.where((e) => e.startsWith(query)).toList(),
)

Async / lazy-loaded items

Just rebuild with a new items list — the overlay refreshes automatically:

SearchableDropdownPro<City>(
  items: _cities,          // starts empty, populated after API call
  displayString: (c) => c.name,
  onSelected: (_) {},
  hintText: 'City',
)

Programmatic control

final _ctrl = SearchableDropdownController();

@override
void dispose() {
  _ctrl.dispose();
  super.dispose();
}

// Widget
SearchableDropdownPro<String>(
  items: items,
  displayString: (e) => e,
  onSelected: (_) {},
  hintText: 'Pick one',
  controller: _ctrl,
)

// Elsewhere in your code
_ctrl.open();
_ctrl.close();
_ctrl.clear();
_ctrl.setText('Pre-filled value');

Theming

SearchableDropdownPro<String>(
  items: items,
  displayString: (e) => e,
  onSelected: (_) {},
  hintText: 'Themed',
  decoration: SearchableDropdownDecoration(
    dropdownColor: Colors.grey.shade900,
    dropdownElevation: 8,
    borderRadius: BorderRadius.circular(12),
    itemTextStyle: const TextStyle(color: Colors.white),
    selectedItemColor: Colors.blue.withOpacity(0.2),
    dividerColor: Colors.grey.shade700,
    noMatchText: 'Nothing found 🤷',
    suffixIcon: const Icon(Icons.arrow_drop_down, color: Colors.blue),
  ),
)

API reference