选择器

Selector

Multi-type support Platform Selector for Flutter. This library helps you write platform-specific code in a clean and functional way.

Features

• Basic Selector (selector): Choose a value based on the current platform (Android, iOS, macOS, Windows, Linux, Fuchsia, Web). All platform parameters are required. Throws UnsupportedError if the platform is not identified.
• Optional Selector (optionalSelector): Similar to selector, but platform parameters are optional. Returns null if the current platform's value is not provided or if the platform is unidentified.
• Device Selector (deviceSelector): Select a value based on device type (mobile, desktop, web). All device type parameters are required. Throws UnsupportedError if the device type is not identified.
• Optional Device Selector (optionalDeviceSelector): Similar to deviceSelector, but device type parameters are optional. Returns null if the current device type's value is not provided or if the device type is unidentified.
• OrElse Selector (selectOrElse): Provides a fallback orElse value if the current platform's value is not provided.
• Query (isMobile, isDesktop): Convenient getters to check if the current device is mobile or desktop.

Usage

Basic selector (selector)

Use selector when you need to provide a value for every supported platform.

import 'package:selector/selector.dart';

String message = selector(
      web: 'Hello Web!',
      android: 'Hello Android!',
      ios: 'Hello iOS!',
      fuchsia: 'Hello Fuchsia!',
      linux: 'Hello Linux!',
      macos: 'Hello macOS!',
      windows: 'Hello Windows!',
);
print(message); // e.g., "Hello Android!" on an Android device

Optional selector (optionalSelector)

Use optionalSelector when you only need to provide values for a subset of platforms. If the current platform's value is not provided, it returns null.

import 'package:selector/selector.dart';

String? specialMessage = optionalSelector(
      android: 'Special message for Android!',
      ios: 'Special message for iOS!',
);
print(specialMessage); // "Special message for Android!" on Android, null on macOS

Device selector (deviceSelector)

Use deviceSelector to differentiate between mobile, desktop, and web environments.

import 'package:selector/selector.dart';

String deviceType = deviceSelector(
      mobile: 'This is a mobile device.',
      desktop: 'This is a desktop device.',
      web: 'This is a web browser.',
);
print(deviceType); // e.g., "This is a mobile device." on an iOS phone

Optional Device selector (optionalDeviceSelector)

Similar to deviceSelector, but device type parameters are optional. Returns null if the current device type's value is not provided.

import 'package:selector/selector.dart';

String? specificDeviceMessage = optionalDeviceSelector(
      mobile: 'Mobile specific UI.',
      web: 'Web specific UI.',
);
print(specificDeviceMessage); // "Mobile specific UI." on Android, null on Windows desktop

OrElse selector (androidOrElse, iosOrElse, etc.)

Use these platform-specific orElse functions for direct, explicit choices.

import 'package:selector/selector.dart';

String admobKey = androidOrElse('android-key', 'iOS-key');
String iosPreferredKey = iosOrElse('iOS-key', 'android-key');
String mobileSpecific = mobileOrElse('mobile_value', 'default_value');
String desktopSpecific = desktopOrElse('desktop_value', 'default_value');
String webSpecific = webOrElse('web_value', 'default_value');

Alternatively, use the more flexible selectOrElse for multiple platform options:

import 'package:selector/selector.dart

String apiKey = selectOrElse(
      android: 'YOUR_ANDROID_API_KEY',
      ios: 'YOUR_IOS_API_KEY',
      orElse: 'DEFAULT_API_KEY', // Used if platform is not Android or iOS
);
print(apiKey); // "YOUR_ANDROID_API_KEY" on Android, "DEFAULT_API_KEY" on Windows

Query

Convenient getters to check the device type.

import 'package:selector/selector.dart';

print('isDesktop: $isDesktop'); // true if on Windows, Linux, macOS
print('isMobile: $isMobile');   // true if on Android, iOS, Fuchsia