Flutter SDK
Flutter 插件基于原生 iOS / Android SDK 封装,统一暴露一个 Dart 的 CaptchalaClient。同时支持 Linux / macOS / Windows 桌面端(嵌入式 WebView)。
GitHub 上的示例
📦
Captcha-La/flutter-demo — 完整可运行示例,包含所有集成步骤。
安装
Add the package from pub.dev:
# pubspec.yaml
dependencies:
captchala: ^1.3.2
http: ^1.2.0 # used by the demo's token-fetch helpersflutter pub get
flutter run # auto-picks the foreground device
# or:
flutter run -d <device-id>For iOS / macOS the first build runs pod install automatically. Make sure ios/Podfile declares platform :ios, '13.0' (or higher).
快速开始
import 'package:flutter/material.dart';
import 'package:captchala/captchala.dart';
class LoginScreen extends StatefulWidget {
const LoginScreen({super.key});
@override
State<LoginScreen> createState() => _LoginScreenState();
}
class _LoginScreenState extends State<LoginScreen> {
String _status = 'Tap to verify';
bool _verifying = false;
Future<void> _runVerify() async {
setState(() { _verifying = true; _status = 'Fetching server_token...'; });
// 1. Fetch a one-shot server_token from YOUR backend.
final initialToken = await fetchServerTokenFromYourBackend();
// 2. Build config from your business action.
final config = CaptchalaConfig(
appKey: 'YOUR_APP_KEY',
action: 'login', // login, register, pay, …
lang: 'en', // en, zh-CN, zh-TW, ja, ko, ms, vi, id
theme: 'light', // 'light' | 'dark'
enableVoice: true,
enableOfflineMode: true,
maskClosable: false,
serverToken: initialToken,
);
// 3. Initialize, register callbacks, then call verify().
final client = await CaptchalaClient.instance.initialize(config);
client.setCallbacks(
onSuccess: (r) async {
// Send r.passToken to YOUR backend for validation.
if (!mounted) return;
setState(() { _status = 'OK: ${r.passToken}'; _verifying = false; });
},
onFail: (e) { if (mounted) setState(() { _status = 'fail: ${e.code}'; _verifying = false; }); },
onError: (e) { if (mounted) setState(() { _status = 'error: ${e.code} ${e.message}'; _verifying = false; }); },
onClose: () { if (mounted && _verifying) setState(() { _status = 'closed'; _verifying = false; }); },
onServerTokenExpired: () => fetchServerTokenFromYourBackend(),
);
await client.verify();
}
@override
Widget build(BuildContext context) {
return Scaffold(
body: Center(
child: Column(mainAxisSize: MainAxisSize.min, children: [
ElevatedButton(
onPressed: _verifying ? null : _runVerify,
child: Text(_verifying ? 'Verifying...' : 'Verify with CAPTCHA'),
),
const SizedBox(height: 12),
Text(_status, style: const TextStyle(fontFamily: 'monospace')),
]),
),
);
}
}API 一览
| 符号 | 用途 |
|---|---|
CaptchalaClient.instance | 插件的单例访问入口。 |
CaptchalaConfig(...) | 普通 Dart 数据类:appKey、action、lang、theme、enableVoice、enableOfflineMode、maskClosable、serverToken。 |
await client.initialize(config) | 应用配置,返回同一个 client 实例,便于链式调用 setCallbacks。 |
setCallbacks(...) | 注册 onSuccess、onFail、onError、onClose、onServerTokenExpired 回调。 |
await client.verify() | 打开原生验证码视图(Android:在 Flutter 之上呈现 Activity;iOS:UIViewController)。 |
CaptchalaResult | onSuccess 中返回的对象。字段:passToken、challengeId、ttl、isOffline、isClientOnly。 |
服务端校验
把 result.passToken(或 result.token)发到你的后端,再调用 CaptchaLa API 校验。绝不要在客户端代码中暴露 X-App-Secret。
POST https://apiv1.captcha.la/v1/validate
X-App-Key: YOUR_APP_KEY
X-App-Secret: YOUR_APP_SECRET
Content-Type: application/json
{ "pass_token": "<result.passToken>", "client_ip": "<end-user IP>" }完整校验接口及 X-App-Key / X-App-Secret 流程见 API 参考。
常见问题
iOS pod install 失败
在ios/Podfile中设置platform :ios, '13.0'(或更高)。切换插件版本后执行flutter clean && flutter pub get && cd ios && pod install。Android
minSdkVersion不一致
将android/app/build.gradle的minSdkVersion提升到 21。低于该版本时原生 SDK 会拒绝编译。回调在后台 isolate 上触发
在回调中调用setState前,先用if (mounted)守卫 UI 状态变更。demo 中每个会更新状态的回调都做了这个检查。桌面端(Linux / Windows / macOS)
Linux 需要 GTK3 + WebKitGTK + libcurl。Windows 需要 Edge WebView2 Runtime(Windows 10 1809+)。macOS 桌面端会自动使用系统 WebView。
环境要求
- Flutter 3.10+ / Dart 3.0+
- Android:
minSdkVersion 21(Android 5.0+) - iOS: 13.0+ with CocoaPods
- Desktop (optional): GTK3 + WebKitGTK on Linux, WebView2 Runtime on Windows 10 1809+