am_searchable_dropdown 🎯

A highly customizable and feature-rich searchable dropdown for Flutter. It supports single-select, multi-select with checkboxes, and works seamlessly with any generic data model <T>.

Designed for developers who need full control over the UI while keeping the implementation simple and clean.

✨ Features

  • 🔍 Powerful Search: Instant local filtering or server-side (remote) search callbacks.
  • 🎯 Single & Multi Select: Support for both single item selection and multiple items with checkboxes.
  • 🏗️ Generic Type Support <T>: Use it with Strings, Integers, or your own complex Data Models.
  • 🎨 Full UI Customization: Provide your own builders for the Header and List Items.
  • 🛡️ Form Validation: Integrated with Flutter's FormField for easy validation and error handling.
  • ⚡ Performance Optimized: Built-in debouncing (500ms) for smooth search, especially with remote APIs.
  • 📱 Safe Overlay Handling: Intelligent positioning to avoid being cut off by screen edges or the keyboard.

📦 Installation

Add this to your package's pubspec.yaml file:

dependencies:
  am_searchable_dropdown: ^1.0.2

Then run:

flutter pub get

🚀 Quick Start (Basic Usage)

For simple lists like strings, you can get started in seconds:

CustomSearchDropdownWidget<String>(
  itemsList: ["Apple", "Banana", "Cherry", "Date"],
  backgroundColor: Colors.white,
  selectedItem: _selectedFruit,
  onChange: (value) => setState(() => _selectedFruit = value),
  headerBuilder: (context, selectedItem, enabled) => Text(selectedItem ?? "Select Fruit"),
  listItemBuilder: (context, item, isSelected) => Text(item),
)

🎯 Advanced Example (Real-World Models)

Most apps use models. am_searchable_dropdown makes this easy by allowing you to work directly with your objects.

CustomMultiSearchDropdownWidget<User>(
  itemsList: _users, // List<User>
  selectedItems: _selectedUsers, // List<User>
  backgroundColor: Colors.white,
  onChanged: (values) => setState(() => _selectedUsers = values),
  // Transform your model to a searchable string
  itemToString: (user) => user.name, 
  headerBuilder: (context, selectedItems, enabled) {
    return Text(
      selectedItems.isEmpty 
        ? "Select Users" 
        : selectedItems.map((e) => e.name).join(", "),
    );
  },
  listItemBuilder: (context, user, isSelected) {
    return ListTile(
      title: Text(user.name),
      subtitle: Text(user.email),
      trailing: isSelected ? Icon(Icons.check_circle, color: Colors.blue) : null,
    );
  },
)

🌟 Feature Breakdown

1. Custom Model Support

Use itemToString to define how your complex objects should be searched. No need to override toString() in your class (though you still can!).

itemToString: (item) => item.fullName,

2. Header Customization

The "Header" is the button that opens the dropdown. You have 100% control over its design using headerBuilder.

headerBuilder: (context, selectedItem, enabled) {
  return Container(
    padding: EdgeInsets.all(12),
    border: Border.all(color: Colors.blue),
    child: Text(selectedItem?.name ?? "Pick a User"),
  );
},

3. List Item UI

Style the items inside the dropdown exactly how you want. You get access to isSelected to highlight the current choice.

listItemBuilder: (context, item, isSelected) {
  return Container(
    color: isSelected ? Colors.blue.withOpacity(0.1) : null,
    child: Text(item.name),
  );
},

4. Search Field Customization

Tweak the appearance of the search input field to match your app's theme.

searchFieldDecoration: InputDecoration(
  hintText: "Search customers...",
  prefixIcon: Icon(Icons.person_search),
  border: OutlineInputBorder(),
),

5. Form Validation & Error UI

Built-in support for validator. You can customize the error text style and border.

validator: (value) => value == null ? "Please select an item" : null,
errorTextStyle: TextStyle(color: Colors.red, fontSize: 13),
errorBorder: Border.all(color: Colors.red, width: 2),

6. Multi Select with Checkboxes

CustomMultiSearchDropdownWidget provides a familiar multi-select interface with checkboxes integrated into the logic.

💡 Best Practices

  1. Unique Types: Ensure your generic type <T> implements == and hashCode correctly if using complex objects.
  2. Debounced Search: If using onSearch for remote APIs, remember that the package already debounces for 500ms to save your backend from too many requests.
  3. Background Color: Match the backgroundColor of the dropdown panel to your app's theme for a seamless experience.

🔗 Links

Developed with ❤️ by Abdul Mannan

Libraries

am_searchable_dropdown
A highly customizable searchable dropdown package for Flutter.